Features and Amenities
Features and Amenities:
Wifi ready study area
Gym and Function Room
Features and Amenities:
2 Lap Pools
Ground Floor Commercial Areas
Features and Amenities:
3 Swimming Pools
Gym and Fitness Center
Outdoor Basketball Court
Contact us today for a no obligation quotation:
Copyright © 2018 SMDC :: SM Residences, All Rights Reserved.
920-331 exam Dumps Source : Communication Server 1000 Rls. 5.0 Database Administrator
Test Code : 920-331
Test Name : Communication Server 1000 Rls. 5.0 Database Administrator
Vendor Name : Nortel
: 55 Real Questions
Is there 920-331 examination new sayllabus available?
in no way ever notion of passing the 920-331 exam answering all questions effectively. Hats off to you killexams. I wouldnt have achieved this fulfillment with out the help of your query and answer. It helped me draw close the principles and that i should solution even the unknown questions. it is the real custom designed material which met my necessity for the duration of coaching. determined 90 percent questions commonplace to the guide and responded them quickly to save time for the unknown questions and it labored. thanks killexams.
Is there a shortcut to clean 920-331 examination?
Passing the 920-331 exam turned into quite hard for me until i was added with the query & solution through killexams. a number of the topics appeared very hard to me. tried plenty to study the books, however failed as time was quick. subsequently, the sell off helped me understand the topics and wrap up my instruction in 10 days time. amazing guide, killexams. My heartfelt way to you.
those 920-331 brand new-the-art dumps works inside the actual test.
I even have renewed my club this time for 920-331 exam. I receive my involvement with killexams.com is so crucial it isnt feasible surrender by means of not having a club. I can just accept as true with killexams.com tests for my exam. Just this site can help me reap my 920-331 accredition and help me in getting above ninety five% marks within the exam. You all are actually making an terrific displaying. Keep it up!
Little effor, Big output, Great questions and answers.
This is to tell that I passed 920-331 exam the opportunity day. This killexams.com questions solutions and exam simulator changed into very useful, and that i dont assume i might have accomplished it without it, with simplest every week of steerage. The 920-331 questions are real, and this is exactly what I noticed within the check center. Moreover, this prep corresponds with all the key problems of the 920-331 exam, so i used to be truly organized for a few questions that have been barely different from what killexams.com provided, but on the equal problem be counted. But, I passed 920-331 and happy approximately it.
try out those real 920-331 state-of-the-art and updated dumps.
This killexams.com from helped me get my 920-331 companion affirmation. Their material are in fact useful, and the exam simulator is genuinely great, it absolutely reproduces the exam. Topics are clear very with out issues the usage of the killexams.com test dump. The exam itself become unpredictable, so Im pleased I appliedkillexams.com . Their packs unfold all that I want, and i wont get any unsavory shocks amid your exam. Thanx guys.
Very smooth to get licensed in 920-331 examination with this have a look at manual.
I prepare people for 920-331 exam subject and refer all to your site for further developed preparing. This is positively the best site that gives solid exam material. This is the best asset I know of, as I have been going to numerous locales if not all, and I have presumed that killexams.com Dumps for 920-331 is truly up to the mark. Much obliged killexams.com and the exam simulator.
wherein to register for 920-331 exam?
I subscribed on killexams.com with the useful resource of the suggession of my friend, as a manner to get a few more useful resourcefor my 920-331 exams. As speedy as I logged on to this killexams.com I felt comfy and relieved because I knew this can assist me get via my 920-331 test and that it did.
Questions were exactly identical as i purchased!
Thankyou killexams..I have cleared my 920-331 exam with 92%. Your question economic team have become very beneficial. If all people practices a hundred% certainly from your question set and research all the questions rightly, then hes going to definately prevail. Till now i have cleared three extraordinary tests all with the help of your site. Thanks again.
am i capable of locate dumps Q & A brand new 920-331 examination?
Getting geared up for 920-331 books may be a complex technique and nine out of ten probabilities are that youll fail if you do it with none suitable steerage. Thats where fantastic 920-331 e book comes in! It gives you with inexperienced and groovy statistics that not simplest enhances your schooling however also gives you a clean reduce chance of passing your 920-331 download and getting into any university with none despair. I prepared thru this super software and i scored 40 two marks out of 50. I am able to guarantee you that itll by no means will let you down!
I sense very assured with 920-331 exam bank.
This practise kit has helped me skip the exam and become 920-331 licensed. I could not be extra excited and thankful to killexams.com for such an clean and dependable practise tool. I am able to affirm that the questions within the package are real, this is not a fake. I chose it for being a reliable (endorsed with the aid of a friend) way to streamline the exam preparation. Like many others, I couldnt come up with the money for studying full time for weeks or even months, and killexams.com has allowed me to squeeze down my practise time and still get a terrific end result. super answer for busy IT professionals.
informationMicrosoft-Nortel See Unified Communications features
The Alliance currently gained three new consumers as smartly, together with Indiana school, U.okay.-based Worcestershire health suggestions and Communications expertise functions, and an IT and telephony company called 4ward.
Microsoft and Nortel formed the imaginitive Communications Alliance in July of remaining yr with the goal of offering unified communications solutions to agencies. beneath the Alliance, the corporations initiated joint analysis and construction efforts. They also created customer demonstration facilities and engaged in joint earnings and advertising.
within the Alliance's preliminary press unencumber, Jeff Raikes, Microsoft's company Division president, stated that the joint unified communications solution would enable a "single identity across email, voice mail, voice over internet protocol (VoIP) call processing, immediate messaging and video."
The Alliance's principal product is known as Nortel Converged office, a unified communications system that integrates Nortel's VoIP telephony gadget with Microsoft's server know-how.
The leading components of Converged workplace encompass:
there's also a Nortel software center part that helps optional capabilities, including internet integration, interactive voice response and contact middle functions.
Unified communications receives described in a lot of methods, but according to the IEEE, it typically encompasses "unified messaging, collaboration and interaction systems." These techniques also usually permit true-time and close precise-time communications. furthermore, blended media (voice, e mail, fax, and many others.) may also be accessed from a single utility, impartial of the entry device.
competitors in the unified communications area is thick with big names. In March of this 12 months, IBM and Cisco, announced a collaborative effort on unified messaging client expertise referred to as Unified Communications and Collaboration (UC2). UC2 is in keeping with open technologies, corresponding to Eclipse construction environment and the Open capabilities Gateway Initiative framework. Citrix systems and Nokia, among others, have expressed help for the UC2 platform.
below the IBM-Cisco unified communications partnership, Cisco plans to sell IBM's Lotus Sametime collaboration solution and IBM plans to sell Cisco's Unified Communications supervisor, Cisco unity and Cisco Unified MeetingPlace products. The whole unified communications answer is designed and delivered through IBM global technology functions.
Kurt Mackie is senior information producer for the 1105 business Computing neighborhood.
As mentioned in a old tip, businesses are imposing IP telephony greater generally on their statistics infrastructures. The increased deployment has created a need for licensed IP telephony engineers to supply confirmed, most suitable-of-breed technology.
The IP telephony certifications Nortel presently presents are divided into 4 classes: assist specialist, Design professional, support professional, and Design skilled. This tip discusses the Nortel help tune.
The aid professional certifications are intended to show an individual's means to put into effect, operate, and troubleshoot a Nortel Networks IP Telephony answer. The help specialist certification displays a candidate with three to six months of experience that may address activities technical issues of a typical Nortel IP Telephony answer.
NNCSS - VoIP Succession BCM 3.0
This certification assessments the means to put into effect, function, and troubleshoot the business Communications manager 3.0. This certification covers hardware, beginning-up, facts and voice networking, purposes, and troubleshooting the BCM. To flow the certification, two tests have to be effectively completed: technology requirements and Protocols for IP Telephony options, and Succession BCM 3.0. The expertise necessities and Protocols for IP Telephony solutions examination is an outline of convergence technologies.
NNCSS - CallPilot Rls. 2.0
This certification exams the ability to put in force, function, and troubleshoot the VoIP CallPilot 2.0. This certification covers hardware, administration, interoperability with Meridian 1 switches, and safety of a single web site CallPilot gadget. To pass the certification, two assessments must be efficaciously achieved: Meridian Database and CallPilot 2.0.
NNCSS - Symposium call middle Server or Symposium name center Server installing and protection
These two certifications check the capability to put in force, operate, and troubleshoot the Symposium call center Server. each certifications cowl hardware, software installation, administration, and maintenance of Symposium call center Server four.2, Symposium web customer 4.0, and Symposium express 3.0. however, the Symposium call core Server certification also checks the structure, customized configuration and integration of the server. To flow both of these certifications, one examination need to be efficiently achieved: Symposium call core or Symposium call core setting up and maintenance, respectively.
NNCSS - Symposium name core TAPI/Agent or name center TAPI/Agent installation and protection
These two certifications test the capability to enforce, function, and troubleshoot the Symposium call core TAPI/Agent. both certifications cover hardware, application installing, administration, and maintenance of Symposium TAPI 2.3 and Symposium Agent 2.three. however, the Symposium call middle TAPI/Agent certification also assessments the architecture, integration, and custom configuration of the TAPI/Agent. To pass either of these certifications, one exam must be correctly completed: Symposium call middle TAPI/Agent or Symposium name middle TAPI/Agent Inst/leading, respectively.
NNCSS - Symposium categorical name core or Symposium categorical name middle setting up and protection
These certifications test the ability to put into effect, function, and troubleshoot the Symposium express call center. both certifications cowl hardware, software installing, administration, and renovation of Symposium categorical call center 4.2. besides the fact that children, the Symposium express call middle certification also checks the structure and integration of the call middle. To flow both of the certifications, one exam must be efficiently achieved: Symposium specific call middle or Symposium specific call center Inst and Maint respectively.
NNCSS - VoIP Multimedia conversation Server (MCS) 5100 2.0
This certification exams the capability to put into effect, function, and troubleshoot the VoIP Multimedia verbal exchange Server (MCS) 5100 2.0. This certification covers installation of the hardware and software, configuration, maintenance, and management of the Multimedia communique Server (MCS) 5100 2.0. To move the certification, two checks need to be correctly achieved: know-how standards and Protocols for IP Telephony solutions, and VoIP Multimedia communication Server (MCS) 5100 2.0. The technology standards and Protocols for IP Telephony options examination is an outline of convergence technologies.
NNCSS - VoIP Succession a thousand/1000M Rls. three.0 DB Administrator
This certification tests the capacity to preserve and troubleshoot the VoIP Succession a thousand/1000M Rls. three.0 DB Administrator. This certification covers the structure, configuration, preservation, and management of the Meridian 1, Succession 1000 Rls. three.0, and Succession 1000M Rls. three.0 the usage of basic Alternate Route option (BARS) and network Alternate Route alternative (NARS). To flow the certification, two checks must be correctly accomplished: know-how necessities and Protocols for IP Telephony solutions, and Succession a thousand/1000M Rls. three.0 DB Administrator.
NNCSS - VoIP Succession a thousand/1000M Rls. three.0 installation and protection
This certification tests the capability to set up, configure, and maintain the VoIP Succession a thousand/1000M Rls. three.0. This certification covers the setting up, structure, configuration, maintenance, and management of the Meridian 1, Succession a thousand Rls. three.0, and Succession 1000M Rls. 3.0, internet Telephones i2xxx, and Optivity Telephony manager (OTM) 2.1. To flow the certification, three exams should be successfully accomplished: expertise necessities and Protocols for IP Telephony options, and Succession one thousand/1000M Rls. 3.0 for Technicians, and Succession a thousand/1000M Rls. 3.0.
The assist expert certifications construct on the professional's capabilities via demonstrating their skill to enforce, operate, and troubleshoot an superior Nortel Networks IP Telephony answer. The guide professional certifications mirror a candidate with six to 12 months of arms-on adventure with the means to guide or assist intermediate-degree personnel to keep complicated Nortel IP Telephony options.
NNCSE - CallPilot 2.0 Unified Messaging options
This certification tests the skill to put into effect, operate, troubleshoot and optimize the VoIP CallPilot Unified Messaging solution 2.0. This certification covers the installation, administration, interoperability, protection, upgrade techniques and feature utilization for a multi web page CallPilot device. To move the certification, the candidate ought to first achieve their NNCSS - CallPilot Rls. 2.0. as a result, the CallPilot 2.0 Unified Messaging options should be efficiently completed to acquire this certification.
NNCSE - Contact center
This certification assessments the capacity to implement, function, troubleshoot and optimize the Contact core products. This certification covers the candidate's capabilities on the Symposium call middle Server (SCCS)/Symposium categorical call middle/Symposium net customer, Symposium TAPI provider company (TAPI SP), Symposium Agent, and the Symposium internet core Portal. To flow the certification, the candidate need to first acquire their NNCSS - Symposium call core Server and the NNCSS - Symposium name middle TAPI/Agent certification. as a result, the Contact core exam have to be correctly completed to obtain this certification.
NNCSE - IP Convergence Succession 1000/1000M Rls. 3.0
This certification checks the capacity to installation, configure, keep, and optimize the VoIP Succession a thousand/1000M Rls. three.0. This certification covers the configuration, succession branch workplace (BO), far off office, operation, and Meridian 1 to Succession 1000M 3.0 migration strategies for the Succession a thousand/1000M Rls. three.0, information superhighway Telephones i2xxx, faraway office 91xx, and Optivity Telephony manager (OTM) 2.1. To pass the certification, the candidate have to first acquire their NNCSS - VoIP Succession CSE one thousand Rls. 2.0 or the VoIP Succession one thousand/1000M Rls. three.0 setting up & maintenance certification. subsequently, one other greater complicated version of the Succession a thousand/1000M Rls. three.0 examination ought to be efficiently achieved to achieve this certification.
within the IT business, certifications are a means to validate someone's capabilities within a precise area. The above Nortel IP Telephony certifications are one of the crucial equipment that may demonstrate the capabilities of an IP Telephony aid professional. These certifications could not exchange years of business event, but they do supply the basis to support and control Nortel Voice over IP solutions.
The next tip will focus on Nortel's Design IP Telephony certification song.
Richard Parsons (CCIE#5719) is a manager of professional services for Callisma Inc., a unconditionally owned subsidiary of SBC. He has constructed an excellent groundwork in networking ideas, superior troubleshooting, and monitoring in areas corresponding to optical, ATM, VoIP, routed, routing, and storage infrastructures. prosperous resides in Atlanta GA, and is a graduate of Clemson school. His background comprises senior and essential consulting positions at international community functions, Lucent, and Callisma.
informationMicrosoft and Nortel present Alliance Roadmap
the two businesses first announced their collaboration remaining summer time.
The highway map contains three new joint options “to dramatically improve enterprise communications by breaking down the boundaries between voice, e mail, quick messaging, multimedia conferencing and different styles of conversation,” in line with a statement by using the two corporations.
also included in the announcement are eleven new implementation functions from Nortel and the hole of greater than 20 joint demonstration facilities the place shoppers can event the technology, the observation continued.
furthermore, the two agencies mentioned they have signed agreements with dozens of purchasers, and have developed a “pipeline of a whole lot of prospects who want to recognise the merits of unified communications.”
From Microsoft's viewpoint, it's all a part of the business's lengthy-term play to merge every kind of communications and messaging into a single framework. A yr ago, the enterprise announced that it become merging its exchange Server community with its real-Time Collaboration (RTC) community, and that it had begun to think of the two technologies comprising a "platform."
the new community became named the Unified Communications community (UCG) and resides in Microsoft's company Division. The theory for the new community emanated from a imaginative and prescient of adding continuity to a myriad of communications gadgets, technologies and modes -- from electronic mail and rapid messaging to Voice over internet Protocol (VoIP), audio/video and web conferencing -- in a unified manner.
The three new joint options announced with the aid of the alliance this week are named Unified Communications built-in department, Unified Messaging, and Conferencing.
When it is available within the fourth quarter, UC built-in department will include Nortel and Microsoft technology on a single piece of hardware that grants VoIP and unified communications in remote offices.
Coming a bit of prior in the 2d quarter, Unified Messaging will purpose to simplify consumer deployments, native session initiation protocol (SIP) interoperability between the Nortel verbal exchange Server 1000 and Microsoft change Server 2007. The answer comprises Nortel skilled functions for design, deployment and assist.
additionally coming in the fourth quarter, Conferencing will prolong Nortel Multimedia Conferencing to Microsoft workplace Communicator 2007. It aims to deliver a single customer experience constant across purposes akin to voice, speedy messaging, presence, and audio- and videoconferencing.
This year, the groups also plan to extend their present unified communications solution — a unified desktop and gentle cellphone for VoIP, email, speedy messaging and presence — to the Nortel verbal exchange Server 2100, a carrier-grade enterprise telephony product aiding up to 200,000 users on a single device, in accordance with business statements.
As for the highway map, the two agencies have outfitted more than 20 joint demonstration centers in North the usa, Europe and Asia, with more than one hundred further facilities scheduled to open through midyear.
Nortel has also introduced 11 core integration capabilities to help consumers build, install and aid joint unified communications solutions, including conclusion-to-conclusion task administration. Nortel claims it has already proficient greater than 2,200 VoIP consultants to bring these features and should add greater as deployment ramps up.
Stuart J. Johnston has lined expertise, mainly Microsoft, due to the fact February 1988 for InfoWorld, Computerworld, counsel Week, and pc World, as well as for commercial enterprise Developer, XML & internet capabilities, and .web magazines.
While it is hard errand to pick solid certification questions/answers assets regarding review, reputation and validity since individuals get sham because of picking incorrectly benefit. Killexams.com ensure to serve its customers best to its assets as for exam dumps update and validity. The greater part of other's sham report objection customers come to us for the brain dumps and pass their exams cheerfully and effortlessly. They never bargain on their review, reputation and quality because killexams review, killexams reputation and killexams customer certainty is imperative to us. Extraordinarily they deal with killexams.com review, killexams.com reputation, killexams.com sham report grievance, killexams.com trust, killexams.com validity, killexams.com report and killexams.com scam. On the off chance that you see any false report posted by their rivals with the name killexams sham report grievance web, killexams.com sham report, killexams.com scam, killexams.com protestation or something like this, simply remember there are constantly terrible individuals harming reputation of good administrations because of their advantages. There are a great many fulfilled clients that pass their exams utilizing killexams.com brain dumps, killexams PDF questions, killexams questions, killexams exam simulator. Visit Killexams.com, their example questions and test brain dumps, their exam simulator and you will realize that killexams.com is the best brain dumps site.
1Z0-548 questions answers | 642-243 free pdf download | NS0-156 test questions | C5050-287 test prep | HP2-K21 practice questions | HP2-E29 questions and answers | HP2-E32 real questions | COG-702 bootcamp | 000-718 braindumps | HP0-M24 study guide | MB3-207 free pdf | 920-537 Practice test | NET dumps questions | 700-551 cheat sheets | HP2-B86 mock exam | 000-622 test prep | CAT-200 questions and answers | JN0-343 practice test | ESPA-EST cram | 00M-641 study guide |
Slaughter your 920-331 exam at first attempt!
killexams.com Nortel Certification is indispensable in profession oportunities. Loads of understudies had been whining that there are an excessive number of questions in such a great deal of practice appraisals and exam aides, and they are simply exhausted to have enough cash any more. Seeing killexams.com experts work out this far reaching rendition of brain dumps with real questions in the meantime as in any case guarantee that simply retaining these real questions, you will pass your exam with
A high-quality 920-331 dumps making will be a basic part that creates it easiest for you to require 920-331 certification. In any case, 920-331 braindumps PDF offers agreement for candidates. The IT declaration will be a very important robust enterprise if one does not discover actual route as obvious practice test. Thus, they have got actual and updated dumps for the composition of 920-331 certification test. At killexams.com, they provide completely verified Nortel 920-331 actual Questions and Answers that are simply required for Passing 920-331 exam, and to induce certified with the assistance of 920-331 braindumps. they have an approach to nearly assist people improve their understanding and to memorize the 920-331 and certify. It is a wonderful preference to spice up your profession as Nortel expert within the enterprise. Click http://killexams.com/pass4sure/exam-detail/920-331
killexams.com helps millions of candidates pass the exams and get their certifications. They have thousands of successful reviews. Their dumps are reliable, affordable, updated and of really best quality to overcome the difficulties of any IT certifications. killexams.com exam dumps are latest updated in highly outclass manner on regular basis and material is released periodically. Latest killexams.com dumps are available in testing centers with whom they are maintaining their relationship to get latest material.
killexams.com Nortel Certification study guides are setup by IT professionals. Lots of students have been complaining that there are too many questions in so many practice exams and study guides, and they are just tired to afford any more. Seeing killexams.com experts work out this comprehensive version while still guarantee that all the knowledge is covered after deep research and analysis. Everything is to make convenience for candidates on their road to certification.
We have Tested and Approved 920-331 Exams. killexams.com provides the most accurate and latest IT exam materials which almost contain all knowledge points. With the aid of their 920-331 study materials, you dont need to waste your time on reading bulk of reference books and just need to spend 10-20 hours to master their 920-331 real questions and answers. And they provide you with PDF Version & Software Version exam questions and answers. For Software Version materials, Its offered to give the candidates simulate the Nortel 920-331 exam in a real environment.
We provide free update. Within validity period, if 920-331 exam materials that you have purchased updated, they will inform you by email to download latest version of . If you dont pass your Nortel Communication Server 1000 Rls. 5.0 Database Administrator exam, They will give you full refund. You need to send the scanned copy of your 920-331 exam report card to us. After confirming, they will quickly give you FULL REFUND.
killexams.com Huge Discount Coupons and Promo Codes are as under;
WC2017 : 60% Discount Coupon for all exams on website
PROF17 : 10% Discount Coupon for Orders greater than $69
DEAL17 : 15% Discount Coupon for Orders greater than $99
DECSPECIAL : 10% Special Discount Coupon for All Orders
If you prepare for the Nortel 920-331 exam using their testing engine. It is easy to succeed for all certifications in the first attempt. You dont have to deal with all dumps or any free torrent / rapidshare all stuff. They offer free demo of each IT Certification Dumps. You can check out the interface, question quality and usability of their practice exams before you decide to buy.
920-331 | 920-331 | 920-331 | 920-331 | 920-331 | 920-331
Killexams 000-927 questions and answers | Killexams ITEC-Massage Practice test | Killexams 250-521 pdf download | Killexams C2070-991 exam prep | Killexams MOS-A2K real questions | Killexams 00M-643 cheat sheets | Killexams 1Z0-042 braindumps | Killexams C2090-645 test prep | Killexams CA-Real-Estate practice test | Killexams HP2-T19 test questions | Killexams AND-402 dumps questions | Killexams 000-563 real questions | Killexams 200-355 practice exam | Killexams C2140-819 study guide | Killexams 000-M02 practice test | Killexams A2040-412 dumps | Killexams C2150-196 Practice Test | Killexams HH0-380 questions and answers | Killexams GB0-280 braindumps | Killexams 70-544-CSharp exam questions |
Killexams 00M-227 brain dumps | Killexams 000-842 bootcamp | Killexams HPE6-A29 test prep | Killexams 00M-155 exam questions | Killexams MSC-121 examcollection | Killexams 650-987 free pdf download | Killexams 1Z0-071 practice exam | Killexams 3102-1 free pdf | Killexams 000-M96 test questions | Killexams JK0-U21 braindumps | Killexams A2040-928 cheat sheets | Killexams CQIA study guide | Killexams LE0-628 questions answers | Killexams ISSMP exam prep | Killexams PEGACMBB brain dumps | Killexams OCN sample test | Killexams HPE2-T34 practice test | Killexams BH0-008 practice questions | Killexams SC0-502 study guide | Killexams LOT-917 real questions |
By: Dennis Hartmann
Service provider takeaway: Cisco Unified Communications Manager (CUCM) is the call routing and signaling component of the Cisco Unified Communications solution. This section of the chapter excerpt from the book Implementing Cisco Unified Communications Manager, Part 1 will focus on licensing procedures for CUCM.
Download the .pdf of the chapter here.
Licensing is implemented in CUCM beginning with Release 5.0. Administration of license management is done through CUCM GUI administration, allowing accurate tracking of active device registrations compared to the license units that have been purchased. License enforcement occurs at the time of phone provisioning and CUCM service activation.
The publisher is the only licensing server. The licensing server is the logical component that keeps track of the licenses purchased and the licenses used. If the publisher fails, no new phones can register, and no configuration changes will be allowed. Existing phones will continue to operate during a publisher outage.CUCM tracks the license compliance for devices, applications, and software as follows:
Licenses are created and distributed in accordance with the Cisco FlexLM process. Cisco product license registration is performed at https://www.cisco.com/go/license.
These two types of product IDs are available:
CUCM tracks the number of units required by each device, as shown in Figure 1-7. Each device type corresponds to a fixed number of units. The number of DLUs consumed per device depends on the device type and capabilities of the phone.
The number of units required per device can be viewed from CUCM Administration. DLUs are perpetual and device independent. Figure 1-7 displays the number of DLUs consumed in CUCM 6.0 by some popular phones.
The main components of the license file are as follows:
License files are additive. (Multiple license files can be loaded.) The Cisco FlexLM process is used to obtain licenses, and integrity of license files is assured by a digital signature.
When upgrading from Cisco Unified CallManager 4.x, the number of DLUs required is calculated during the CUCM migration process, and an intermediate XML file containing these license counts is generated. The number of devices and servers that are in the database at the time of migration is the basis for the number of DLUs and node licenses in the interim license file. No additional phones may be added until the interim license file has been replaced by a real license file.
After upgrading to CUCM 6.0(1), use the View File option in the License File Upload window to view the intermediate XML file. Copy and paste the intermediate license file into the CUCM License Upgrade window on Cisco.com to obtain the actual license file. Upload the actual license file to the publisher (license server).
Existing device and node licenses from CUCM 5.x can be used in CUCM 6.x.
Significant fields are highlighted and described as follows:
License File Request ProcessFigure 1-8 displays the license file request process, which includes these steps:1. The customer places an order for CUCM.2. The manufacturing database scans the Product Authorization Key (PAK) and records it against the sales order.3. The product (CD or paper claim certificate) is physically delivered to the customer.4. The customer registers the product at https://www.cisco.com/go/license or a public web page and provides the MAC address of the publisher device that will become the license server.5. The license fulfillment infrastructure validates the PAK, and the license key generator creates a license file.6. The license file is delivered via e-mail to the customer. The e-mail also contains instructions on how to install the license file.7. The customer installs the license file on the license server (publisher).
Obtaining Additional Licenses
The process of obtaining additional DLUs and node licenses is as follows:1. The customer places an order for the additional licenses for a license server (publisherMAC address has to be specified).2. When the order is received, Cisco.com generates a license file with the additional count and sends it to the customer.3. The new license file has to be uploaded to the license server and will be cumulative.Consider this example. A CUCM server has an existing license file that contains 100 DLUs. Another 100 DLUs are purchased. The second license file that is generated will contain only 100 DLUs. When the new license file with 100 DLUs is uploaded to CUCM, the 100 DLUs from the first license file are added to the devices of the second license file, resulting in a total of 200 DLUs.
The key licensing components of CUCM licensing are the license server and the license manager.
The license server service runs on the publisher in the CUCM cluster and is responsible for keeping track of the licenses purchased and consumed. The MAC address of the publisher is required to generate a license file.
License ManagerThe license manager acts as a broker between CUCM applications that use licensing information and the license server. The license manager receives requests from the CUCM applications and forwards the requests to the license server. The license manager then responds back to the application after the request has been processed by the license server. The license manager acts a licensing proxy server.
An administration subsystem and alarm subsystem complete the functional diagram. Details of these two subsystems are as follows:
Issues with the license file occur when there is a version mismatch between the license file and the CUCM (license file version mismatch alarm), or when the number of licenses in the license file is less than the number of phones provisioned (license file insufficient licenses alarm). Another cause of this condition is an invalid MAC address (for instance, after a NIC change).
Figure 1-9 is a functional diagram stepping through the process of a license request, as described in the list that follows:
1. A request for a certain number of DLUs is made by the admin subsystem because of an event (for example, phone registration).2. The License Manager service on a CUCM subscriber forwards the request to the publisher server running the License Server service.3. The License Server service receives the license request event and allocates the required number of DLUs required based on the type of device. If not enough license units are available to accommodate the request, a deny message is sent back to the license manager on the subscriber server. If resources are available, the license server grants the request and sends a grant message to the license manager on the subscriber server.4. The License Manager service on the subscriber server receives the license grant or deny message and allows the phone to register.5. If the license request was denied, the subscriber server generates an alarm in the alarm subsystem. The deny message will be available in the CUCM syslog server by default.
Calculating License UnitsTo calculate the number of phone licenses required, follow these steps:
Step 1 Choose System > License > License Unit Calculator. The License UnitCalculator window displays. The number of license units consumed per device and the current number of devices display as shown in Figure 1-10.
Step 2 In the Number of Devices column, enter the desired number of devices, corresponding to each node or phone.
Step 3 Click Calculate. The total number of CUCM node license units and DLUs required for specified configuration will display.
License Unit ReportingLicense unit reports can be run to verify the number of licenses consumed and available for future expansion. Use the following procedure to generate a license unit report:
Step 1 Choose System > License > License Unit Report.
Step 2 The License Unit Report window displays as shown in Figure 1-11. This window displays the number of phone licenses and number of node licenses, in these categories:
License files (CCMxxxxx.lic) are uploaded to the publisher (license server). To upload a license file to the publisher server, follow these steps:
Step 1 Ensure that the license file is downloaded to a local PC.
Step 2 From the PC and using a supported browser, log in to CUCM Administration.
Step 3 Choose System > License > License File Upload, as shown in Figure 1-12. The License File Upload window displays.
Step 4 In the window shown in Figure 1-13, click Upload License File.
Step 5 Click Browse to choose the license file from the local directory.
Step 6 Click Upload.
Step 7 After the upload process has completed, click the Continue prompt when it appears. The content of the newly uploaded license file will display.
Implementing Cisco Unified Communications Manager, Part 1 Cisco Unified Communications Manager Architecture Introduction CUCM Overview CUCM Hardware, Software, and Clustering CUCM Licensing Summary CUCM Review Quiz
Reproduced from the book Implementing Cisco Unified Communications Manager, Part 1. Copyright 2008, Cisco Systems, Inc.. Reproduced by permission of Pearson Education, Inc., 800 East 96th Street, Indianapolis, IN 46240.
Title: C-Level/President Manager VP Staff (Associate/Analyst/etc.) DirectorFunction:
Role in IT decision-making process: Align Business & IT Goals Create IT Strategy Determine IT Needs Manage Vendor Relationships Evaluate/Specify Brands or Vendors Other Role Authorize Purchases Not InvolvedWork Phone: Company: Company Size: Industry: Street Address City: Zip/postal code State/Province: Country:
Occasionally, they send subscribers special offers from select partners. Would you like to receive these special partner offers via e-mail? Yes No
Your registration with Eweek will include the following free email newsletter(s): News & Views
By submitting your wireless number, you agree that eWEEK, its related properties, and vendor partners providing content you view may contact you using contact center technology. Your consent is not required to view content or use site features.
RegisterContinue without consent
In the world of technology computer networks have increased the efficiency and speed of the systems and the IP has made it possible for computers across the globe to communicate easily. Learn how these advantages can help you and how networking and Internet are used in Red Hat Linux.This chapter is from the book
IN THIS CHAPTER
Types of Networks and How They Work
Communicate over a Network
Tutorial: Using pine as a Newsreader
Netnews with Mozilla
WWW: World Wide Web
The communications facilities linking computers are continually improving, allowing faster and more economical connections. The earliest computers were unconnected stand-alone machines. To transfer information from one system to another, you had to store it in some form (usually magnetic tape, paper tape, or punch cards—called IBM or Hollerith cards), carry it to a compatible system, and read it back in. A notable advance occurred when computers began to exchange data over serial lines, although the transfer rate was slow (hundreds of bits per second). People quickly invented new ways to take advantage of this computing power, such as e-mail, news retrieval, and bulletin board services. With the speed of today's networks, it is normal for a piece of e-mail to cross the country or even travel halfway around the world in a few seconds.
It would be difficult to find a computer facility that does not include a LAN to link the systems. GNU/Linux systems are typically attached to an Ethernet (page 1466) network. Wireless networks are becoming prevalent as well. Large computer facilities usually maintain several networks, often of different types, and almost certainly have connections to larger networks (company- or campuswide and beyond).
The Internet is a loosely administered network of networks (an internetwork) that links computers on diverse LANs around the globe. An internet (small i ) is a generic network of networks that may share some parts in common with the public Internet. It is the Internet that makes it possible to send an e-mail message to a colleague thousands of miles away and receive a reply within minutes. A related term, intranet, refers to the networking infrastructure within a company or other institution. Intranets are usually private; access to them from external networks may be limited and carefully controlled, typically using firewalls (page 358).
Over the past decade many network services have emerged and become standard. On GNU/Linux systems, as on UNIX computers, special processes called daemons (page 1463) support such services by exchanging specialized messages with other systems over the network. Several software systems have been created to allow computers to share their filesystems with one another, making it appear as though remote files are stored on local disks. Sharing remote filesystems allows users to share information without knowing where the files physically reside, without making unnecessary copies, and without learning a new set of utilities to manipulate them. Because the files appear to be stored locally, you can use standard utilities (such as cat, vi, lpr, mv, or their graphical counterparts) to work with them.
Developers have been creating new tools and extending existing ones to take advantage of higher network speeds and work within more crowded networks. The rlogin, rsh, and telnet utilities, designed long ago, have largely been supplanted by ssh (secure shell—page 374). The ssh utility allows a user to log in on or execute commands securely on a remote computer. Users rely on such utilities as scp and ftp to transfer files from one system to another across the network. Communication utilities, including e-mail utilities, and chat programs, such as talk, Internet Relay Chat (IRC), ICQ, and AOL Instant Messenger (AIM), have become so prevalent that many people with very little computer experience use them on a daily basis to keep in touch with friends and family.
An intranet is a network that connects computing resources at a school, company, or other organization but, unlike the Internet, typically restricts access to internal users. An intranet is very similar to a LAN but is based on Internet technology. An intranet can provide database, e-mail, and Web page access to a limited group of people, regardless of their geographic location.
The fact that an intranet is able to connect dissimilar machines is one of its strengths. Think of all the machines that are on the Internet: Macs, PCs running different versions of MS Windows, various machines running UNIX and GNU/Linux, and so on. Each of these machines can communicate via IP (page 360), a common protocol. So it is with an intranet: Different machines can all talk to one another.
Another key difference between the Internet and an intranet is that the Internet will transmit only one protocol suite: the IP protocol suite. An intranet can be set up to use a number of protocols, such as IP, IPX, Appletalk, DECnet, XNS, or various other protocols developed by vendors over the years. Although these protocols cannot be transmitted directly over the Internet, you can set up special gateway boxes at remote sites that tunnel or encapsulate these protocols into IP packets in order to use the Internet to pass them.
You can use an extranet (or partner net) to improve your security. A closely related term is virtual private network (VPN). These terms describe ways to connect remote sites securely to a local site, typically by using the public Internet as a carrier and using encryption as a means of protecting data in transit.
As with the Internet, the communications potential of intranets is boundless. You can set up a private chat between people at remote locations, access a company database, see what is new at school, or read about the new university president. Companies that developed products for use on the Internet are investing more and more time and money developing intranet software applications as the intranet market explodes. Following are some words you may want to become familiar with before you read the rest of this chapter. Refer to the Appendix G on page 1453 for definitions.
Computers communicate over networks by using unique addresses assigned by system software. A computer message, called a packet, frame, or datagram, includes the address of the destination computer and the sender's return address. The three most common types of networks are broadcast, point-to-point, and switched. Once popular token-based networks (such as FDDI and Token Ring) are rarely seen anymore.
Speed is important to the proper functioning of the Internet. Newer specifications (cat 6 and cat 7) are being standardized for 1000BaseT (10 gigabits per second, called gigabit Ethernet, or GIG-E) and faster networking. Some of the networks that form the backbone of the Internet run at speeds up to almost 10 gigabytes per second (OC192) to accommodate the ever-increasing demand for network services. Table 9-1 lists some of the common specifications in use today.Table 9-1. Specification
64 kilobits per second
Two DS0 lines plus signaling (16 kilobits per second) or 128 kilobits per second
1.544 megabits per second (24 DS0 lines)
43.232 megabits per second (28 T-1s)
155 megabits per second (100 T-1s)
622 megabits per second (4 OC3s)
2.5 gigabits per seconds (4 OC12s)
9.6 gigabits per second (4 OC48s)Broadcast
On a broadcast network, such as Ethernet, any of the many systems attached to the network cable can send a message at any time; each system examines the address in each message and responds only to messages addressed to it. A problem occurs on a broadcast network when multiple systems send data at the same time, resulting in a collision of the messages on the cable. When messages collide, they can become garbled. The sending system notices the garbled message and resends it after waiting a short but random amount of time. Waiting a random amount of time helps prevent those same systems from resending the data at the same moment and experiencing another collision. The extra traffic that results from collisions can put quite a load on the network; if the collision rate gets too high, the retransmissions result in more collisions, and the network becomes unusable.Point-to-Point
A point-to-point link does not seem like much of a network at all because only two endpoints are involved. However, most connections to WANs are through point-to-point links, using wire cable, radio, or satellite links. The advantage of a point-to-point link is that because only two systems are involved, the traffic on the link is limited and well understood. A disadvantage is that each system can typically be equipped for a small number of such links, and it is impractical and costly to establish point-to-point links that connect each computer to all the rest.
Point-to-point links often use serial lines and modems but can use personal computer parallel ports for faster links between GNU/Linux systems. The use of a modem with a point-to-point link allows an isolated system to connect inexpensively into a larger network.
The most common types of point-to-point links are the ones used to connect to the Internet. When you use DSL1 (digital subscriber line), you are using a point-to-point link to connect to the Internet. Serial lines, such as T-1, T-3, ATM links, and ISDN, are all point to point. Although it might seem like a point-to-point link, a cable modem is based on broadcast technology and in that way is similar to Ethernet.Switched
A switch is a device that establishes a virtual path between source and destination hosts such that each path appears to be a point-to-point link, much like a railroad roundhouse. The telephone network is a giant switched network. The switch brings up and tears down virtual paths as hosts need to communicate with each other. Each host thinks that it has a direct point-to-point path to the host it is talking to. Contrast this with a broadcast network, where each host also sees traffic bound for other hosts. The advantage of a switched network over a pure point-to-point network is that each host requires only one connection: the connection to the switch. Using pure point-to-point connections, each host must have a connection to every other host. Scalability is provided by further linking switches.LAN: Local Area Network
Local area networks (LANs) are confined to a relatively small area—a single computer facility, building, or campus. Today most LANs run over copper or fiberoptic cable, but other, wireless technologies, such as infrared (similar to most television remote control devices) and radio wave, are becoming more popular.
If its destination address is not on the local network, a packet must be passed on to another network by a router (page 357). A router may be a general-purpose computer or a special-purpose device attached to multiple networks to act as a gateway among them.Ethernet
A GNU/Linux system connected to a LAN usually connects to the network by using Ethernet. A typical Ethernet connection can support data transfer rates from 10 megabits per second to 1 gigabit per second, with speed enhancements planned. Owing to computer load, competing network traffic, and network overhead, file transfer rates on an Ethernet are always slower than the maximum, theoretical transfer rate.
An Ethernet network transfers data by using copper or fiberoptic (glass) cable or wireless transmitters and receivers. Originally each computer was attached to a thick coaxial cable (called thicknet) at tap points spaced at six-foot intervals along the cable. The thick cable was awkward to deal with, so other solutions, including a thinner coaxial cable known as thinnet, or 10Base2,2 were developed. Today most Ethernet connections are either wireless or made over unshielded twisted pair (referred to as UTP, Category 3 (cat 3), Category 5 (cat 5), Category 5e (cat 5e) 10BaseT, or 100BaseT) wire—similar to the type of wire used for telephone lines and serial data communications.
A switched Ethernet network is a special case of a broadcast network that works with a network switch, or just switch, which is a special class of hub that has intelligence. Instead of having a dumb repeater (hub) that broadcasts every packet it receives out of every port, a switch learns which devices are connected to which of its ports. A switch sorts packets so that it sends traffic to only the machine the traffic is intended for. A switch also has buffers for holding and queuing packets.
Some Ethernet switches have enough bandwidth to communicate simultaneously, in full-duplex mode, with all the devices that are connected to it. A nonswitched (hub-based) broadcast network can run in only half-duplex mode. Full-duplex Ethernet further improves things by eliminating collisions. Each host can transmit and receive simultaneously at 10/100/1000 megabits per second for an effective bandwidth between hosts of 20/200/2000 megabits per second, depending on the capacity of the switch.Wireless
Wireless networks are becoming increasingly common. They are used in offices, homes, and public places, such as universities and airports. Wireless access points provide functionality similar to an Ethernet hub. They allow multiple users to interact, using a common radio frequency spectrum. A wireless, point-to-point connection allows you to wander about your home or office with your laptop, using an antenna to link to a LAN or to the Internet via an in-house base station. GNU/Linux has drivers for many of the common wireless boards. A wireless access point connects a wireless network to a wired network so that no special protocol is required for a wireless connection. Refer to the Linux Wireless LAN HOWTO and www.hpl.hp.com/personal/Jean_Tourrilhes/Linux.WAN: Wide Area Network
A wide area network (WAN) covers a large geographic area. The technologies (such as Ethernet) used for LANs were designed to work over limited distances and for a certain number of host connections. A WAN may span long distances over dedicated data lines (leased from a telephone company) or radio or satellite links. WANs are often used to interconnect LANs. Major Internet service providers rely on WANs to connect to customers within a country and around the globe.
Some networks do not fit into either the LAN or the WAN designation: A MAN (metropolitan area network) is one that is contained in a smaller geographic area, such as a city. Like WANs, MANs are typically used to interconnect LANs.Internetworking through Gateways and Routers
A LAN connects to a WAN through a gateway, a generic term for a computer or a special device with multiple network connections that passes data from one network to another. The purpose of the gateway is to convert the data traffic from the format used on the LAN to that used on the WAN. Data that crosses the country from one Ethernet to another over a WAN, for example, is repackaged from the Ethernet format to a different format that can be processed by the communications equipment that makes up the WAN backbone. When it reaches the end of its journey over the WAN, the data is converted by another gateway to the format appropriate for the receiving network. For the most part these details are of concern only to the network administrators; the end user does not need to know anything about how the data transfer is carried out.
A router is the most common form of a gateway. Routers play an important role in internetworking. Just as you might study a map to plan your route when you need to drive to an unfamiliar place, a computer needs to know how to deliver a message to a system attached to a distant network by passing through intermediary systems and networks along the way. You can imagine using a giant network road map to choose the route that your data should follow, but a static map of computer routes is usually a poor choice for a large data network. Computers and networks along the route you choose may be overloaded or down, without providing a detour for your message.
Routers communicate with one another dynamically, keeping one another informed about which routes are open for use. To extend the analogy, this would be like heading out on a car trip without consulting a map to find a route to your destination; instead you head for a nearby gas station and ask directions. Throughout the journey, you would continue to stop at one gas station after another, getting directions at each to find the next one. Although it would take a while to make the stops, each gas station would advise you of bad traffic, closed roads, alternative routes, and shortcuts.
The stops the data makes are much quicker than those you would make in your car, but each message leaves each router on a path chosen based on the most current information. Think of it as a GPS (global positioning system) setup that automatically gets updates at each intersection and tells you where to go next, based on traffic and highway conditions.
Figure 9-1 shows an example of how LANs might be set up at three sites interconnected by a WAN (the Internet). In network diagrams such as this, Ethernet LANs are drawn as straight lines, with devices attached at right angles; WANs are represented as clouds, indicating that the details have been left out; wireless connections are drawn as zigzag lines with breaks, indicating that the connection may be intermittent.
Figure 9-1. A slice of the Internet
In Figure 9-1 a gateway or a router relays messages between each LAN and the Internet. Three of the routers in the Internet are shown (for example, the one closest to each site). Site A has a server, a workstation, a network computer, and a PC sharing a single Ethernet LAN. Site B has an Ethernet LAN that serves a printer and four GNU/Linux workstations. A firewall permits only certain traffic between the Internet router and the site's local router. Site C has three LANs linked by a single router, perhaps to reduce the traffic load that would result if they were combined or to keep workgroups or locations on separate networks. Site C includes a wireless access point that enables wireless communication with nearby computers.Firewall
A firewall in a car separates the engine compartment from the passenger compartment, protecting the driver and passengers from engine fires, noise, and fumes. Computer firewalls separate computers from malicious and unwanted users.
A firewall prevents certain types of traffic from entering or leaving a network. A firewall might prevent traffic from your IP address from leaving the network and prevent anyone except users from select domains from using ftp to retrieve data from the network. The implementations of firewalls vary widely, from GNU/Linux machines with two interfaces (page 1473) running custom software to a router (page 1490) with simple access lists to esoteric, vendor-supplied firewall appliances. Most larger installations have at least one kind of firewall in place. A firewall is often accompanied by a proxy server/gateway (page 397) to provide an intermediate point between you and the host you are communicating with.
In addition to those found in multipurpose computers, firewalls are becoming increasingly common in consumer appliances. Firewalls are built into cable modems, wireless gateways, routers, and stand-alone devices.
When your need for privacy is critical, you can meet with a consulting firm that will discuss your security needs, devise a strategy, produce a written implementation policy, and design a firewall for you from scratch. Typically a single GNU/Linux machine can include a minimal firewall. A small group of GNU/Linux machines may have a cheap, slow GNU/Linux machine with two network interfaces and packet-filtering software functioning as a dedicated firewall. One of the interfaces connects to the Internet, modems, and other outside data sources, whereas the other connects, normally through a hub or switch, to the local network's machines. Refer to page 924 for information on setting up a firewall and to Appendix C for a discussion of security.Network Protocols
To exchange information over a network, computers must communicate using a common language, or protocol (page 1486). The protocol determines the format of the message packets. The predominant network protocols used by GNU/Linux systems are TCP and IP, referred to as TCP/IP3 (Transmission Control Protocol and Internet Protocol). Network services that need highly reliable connections, such as ssh and scp, tend to use TCP/IP. Another protocol used for some system services is UDP (User Datagram Protocol). Network services that do not require guaranteed delivery, such as RealAudio and RealVideo, operate satisfactorily with the simpler UDP.4IP: Internet Protocol
Layering was introduced to facilitate protocol design: Layers distinguish functional differences between adjacent protocols. A grouping of layers can be standardized into a protocol model. IP is a protocol and has a corresponding model for what distinguishes protocol layers. The IP model differs from the ISO seven-layer protocol model (also called the OSI model) often illustrated in networking textbooks. IP uses a simplified five-layer model.
The first layer, called the physical layer, describes the physical medium (copper, fiber, wireless) and the data encoding used to transmit signals on that medium (pulses of light, electrical waves, or radio waves, for instance).
The second layer, called the data link layer, covers media access by network devices and describes how to put data into packets, transmit the data, and check it for errors. Ethernet is at this layer, as is 802.11 wireless.
The third layer, called the network layer, frequently uses IP and addresses and routes packets.
The fourth layer, called the transport layer, is where TCP and UDP exist. This layer provides a means for applications to communicate with each other. Common functions of the transport layer include guaranteed delivery, delivery of packets in the order of transmission, flow control, error detection, and error correction. The transport layer is responsible for dividing data streams into packets. This layer also performs port addressing, which allows it to distinguish among different services using the same transport protocol. Port addressing keeps the data from multiple applications using the same protocol (for example TCP) separate.
Anything above the transport layer is the domain of the application and is part of the fifth layer. Unlike the ISO model, the Internet model does not distinguish among application, presentation, and session layers. All the upper-layer characteristics, such as character encoding, encryption, GUI, and so on, are part of the application. Applications choose the transport characteristics they require and choose the corresponding transport layer protocol to send and receive data.
TCP is most frequently run on top of IP in a combination referred to as TCP/IP. TCP provides error recovery and guaranteed delivery in packet transmission order and works with multiple ports so that it can handle more than one application. TCP is a connection-oriented protocol (page 1461), also known as a streams-based protocol. Once established, a TCP connection looks like a stream of data, not individual IP packets. The connection is assumed to remain up and be uniquely addressable. Every piece of information you write to the connection always goes to the same destination and arrives in the order it was sent. Because TCP is connection oriented and establishes what you can think of as a virtual circuit between two machines, TCP is not suitable for one-to-many transmissions (see UDP, following). TCP has builtin mechanisms for dealing with congestion (or flow) control over busy networks and throttles back (slows the speed of data flow) when it has to retransmit dropped packets. TCP can also deal with acknowledgments, wide area links, high delay links, and other situations.UDP: User Datagram Protocol
UDP runs at layer 4 of the IP stack, just as TCP does, but is much simpler. Like TCP, UDP works with multiple ports/multiple applications and has checksums for error detection but does not automatically retransmit packets that fail the checksum. UDP is a packet- (or datagram-) oriented protocol: Each packet must carry its own address and port information. Each router along the way examines each packet to determine the destination one hop at a time. You can broadcast or multicast UDP packets to many destinations at the same time by using special addresses.PPP: Point-to-Point Protocol
PPP provides serial line point-to-point connections that support IP. PPP compresses data to make the most of the limited bandwidth available on serial connections. PPP, which replaces SLIP (Serial Line IP), acts as a point-to-point layer 2/3 transport that many other types of protocols can ride on. PPP is used mostly for IP-based services and connections, such as TCP or UDP.5 For more information, refer to "Internet Configuration Wizard" on page 1023.Xremote and LBX
Two protocols that speed up work over serial lines are Xremote and LBX. Xremote compresses the X Window System protocol so that it is more efficient over slower serial lines. LBX (low-bandwidth X) is based on the Xremote technology and is a part of the X Window System release X11R6.Host Address
Each computer interface is identified by a unique address, or host number, on its network. A system that is attached to more than one network has multiple interfaces, one for each network and each with a unique address.
Each packet of information that is broadcast over the network has a destination address. All hosts on the network must process each broadcast packet to see whether it is addressed to that host.6 If the packet is addressed to a given host, that host continues to process it. If not, the host ignores it.
The network address of a machine is an IP address, which is represented as one number broken into four segments separated by periods (for example, 192.168.184.5). Domain names and IP addresses are assigned through a highly distributed system coordinated by ICANN (Internet Corporation for Assigned Names and Numbers—www.icann.org) via many registrars (see www.internic.net). ICANN is funded by the various domain name registries and registrars and IP address registries, which supply globally unique identifiers for hosts and services on the Internet. Although you may not deal with any of these agencies directly, your Internet service provider does.
How a company uses IP addresses is determined by the system or network administrator. For example, the leftmost two sets of numbers in an IP address might represent a large network (campus- or companywide); the third set might specify a subnetwork (perhaps a department or single floor in a building); and the rightmost number, an individual computer. The operating system uses the address in a different, lower-level form, converting it to its binary equivalent, a series of 1s and 0s. See the following Optional section for more information. Refer to "private address space" on page 1486 in the Glossary for information about addresses you can use on your LAN without registering them.Static versus Dynamic IP addresses
A static IP address is one that remains the same. A dynamic IP address is one that can change each time you connect to your ISP. A dynamic address remains the same during a single login session. Any server (mail, Web, and so on) must have a static address so that clients can find the machine that is the server. End user machines usually work well with dynamic addresses. During a given login session, they can function as a client (your Web browser, for example) because they have a constant IP address. When you log out and log in again, it does not matter that you have a new IP address, because your computer, acting as a client, establishes a new connection with a server. The advantage of dynamic addressing is that it allows inactive addresses to be reused, reducing the total number of IP addresses needed. Refer to "DHCP Client" on page 1028 for more information about dynamic IP addressing.
To facilitate routing on the Internet, IP addresses are divided into classes. Classes, labeled class A through class E, allow the Internet address space to be broken into blocks of small, medium, and large networks that are designed to be assigned based on the number of hosts within a network.
When you need to send a message to an address outside your network, your system looks up the address block/class in its routing table and sends the message to the next router on the way to the final destination. Every router along the way does a similar lookup to forward the message. At the destination, local routers direct the message to the specific address. Without classes and blocks, your host would have to know every network and subnetwork address on the Internet before it could send a message. This would be impractical because of the number of addresses on the Internet.Table 9-2. IP Classes
All Bits (including start bits)
Class D (Multicast)
Class E (Reserved)
Each of the four numbers in the IP address is in the range of 0–255 because each segment of the IP address is represented by 8 bits (an octet), each bit capable of taking on two values; the total number of values is 28 = 256. When you start counting at 0, 1–256 becomes 0–255.7 Each IP address is divided into a net address (netid) portion (which is part of the class) and a host address (hostid) portion. See Table 9-2.
The first set of addresses, defining class A networks, is for extremely large corporations, such as General Electric (22.214.171.124) and Hewlett-Packard (126.96.36.199), or for ISPs. One start bit (0) in the first position designates a class A network, 7 bits hold the network portion of the address (netid), and 24 bits hold the host portion of the address (hostid, Table 9-2). This means that GE can have 224, or approximately 16 million hosts on its network. Unused address space and subnets (page 1495) lower this number quite a bit. The 127.0.0.0 subnet is reserved (page 368), as are 188.8.131.52 and several others.
Two start bits (10) in the first two positions designate a class B network, 14 bits hold the network portion of the address (netid), and 16 bits hold the host portion of the address, for a potential total of 65,534 hosts.8 A class C network uses 3 start bits (100), 21 netid bits (2 million networks), and 8 hostid bits (254 hosts). Today a new large customer will not receive a class A or B network but is likely to receive a class C or several (usually contiguous) class C networks, if merited.
Several other classes of networks exist. Class D networks are reserved for multicast (page 1480) networks. When you run netstat –nr on your GNU/Linux system, you can see whether your machine is a member of a multicast network. A 184.108.40.206 in the Destination column that netstat displays indicates a class D, multicast address (Table 9-2). A multicast is like a broadcast, but only hosts that subscribe to the multicast group receive the message. To use Web terminology, a broadcast is like a push. A host pushes a broadcast on the network, and every host on the network must check each packet to see whether it contains relevant data. A multicast is like a pull. A host will see a multicast only if it registers itself as subscribed to a multicast group or service and pulls the appropriate packets from the network.
Table 9-3 shows some of the computations for IP address 131.204.027.027. Each address is shown in decimal, hexadecimal, and binary. Binary is the easiest to work with for bitwise, (binary) computations. The first three lines show the IP address. The next three lines show the subnet mask (page 1495) in three bases. Next, the IP address and the subnet mask are ANDed together bitwise to yield the subnet number (page 1495), which is shown in three bases. The last three lines show the broadcast address (page 1458), which is computed by taking the subnet number and turning the hostid bits to 1s. The subnet number is the name/number of your local network. The subnet number and the subnet mask determine what range the IP address of your machine must be in. They are also used by routers to segment traffic; see network segment (page 1482). A broadcast on this network goes to all hosts in the range 220.127.116.11 through 18.104.22.168 but will be acted on only by hosts that have a use for it.
Each host on a network must process each broadcast to determine whether the information in the broadcast packet is useful to that host. If a lot of hosts are on a network, each host must process many packets. To maintain efficiency, most networks, particularly shared media networks, such as Ethernet, need to be split into subnetworks, or subnets.9 The more hosts on a network, the more dramatically network performance is impacted. Organizations use router and switch technology called VLANs (virtual local area network) to group similar hosts into broadcast domains (subnets) based on function. It's not uncommon to see a switch with different ports being part of different subnets.Table 9-3. Computations for IP address 131.204.027.027
decimal8C CC 1B 1B hexadecimal
decimalFF FF FF 00 hexadecimal
IP Address bitwise AND
= Subnet Number
Broadcast Address(Set host bits to 1)
A subnet mask (or address mask) is a bit mask that identifies which parts of an IP address correspond to the network address and subnet portion of the address. This mask has 1s in positions corresponding to the network and subnet numbers and 0s in the host number positions. When you perform a bitwise AND on an IP address and a subnet mask (Table 9-3), the result is an address that contains everything but the host address (hostid) portion.
There are several ways to represent a subnet mask: A network could have a subnet mask of 255.255.255.0 (decimal), FFFFFF00 (hexadecimal), or /24 (the number of bits used for the subnet mask). If it were a class B network (of which 16 bits are already fixed), this yields 28 (24 total bits – 16 fixed bits = 8 bits, 28 = 256) networks10 with 28 – 2 (256 – 2 = 254) hosts11 on each network. If you do use a subnet mask, use netconfig to let the system know about it.
For example, when you divide the class C address 22.214.171.124 into eight subnets, you get a subnet mask of 255.255.255.224, FFFFFFE0, or /27 (27 1s). The eight resultant networks are 126.96.36.199, 188.8.131.52, 184.108.40.206, 220.127.116.11, 18.104.22.168, 22.214.171.124, 126.96.36.199, and 188.8.131.52. You can use a Web-based subnet mask calculator to calculate subnet masks (page 1401). To use this calculator to determine the preceding subnet mask, use an IP host address of 184.108.40.206. Go to www.telusplanet.net/public/sparkman/netcalc.htm for a nice subnet calculator.
CIDR: Classless Inter-Domain Routing
CIDR (pronounced cider) allows groups of addresses that are smaller than a class C block to be assigned to an organization or ISP and further subdivided and parceled out. In addition, it helps to alleviate the potential problem of routing tables on major Internet backbone and peering devices becoming too large to manage.
The pool of available IPv4 addresses has been depleted to the point that no one gets a class A address anymore. The trend is to reclaim these huge address blocks, if possible, and recycle them into groups of smaller addresses. Also, as more class C addresses are assigned, routing tables on the Internet are filling up and causing memory overflows. The solution is to aggregate12 groups of addresses into blocks and allocate them to ISPs which in turn subdivide these blocks and allocate them to customers. The address class designations (A, B, and C) described in the previous section are used less today, although subnets are still used. When you request an address block, your ISP usually gives as many addresses as you need and no more. The ISP aggregates several contiguous smaller blocks and routes them to your location. This aggregation is CIDR. Without CIDR, the Internet as they know it would not function.
For example, you might be allocated the 192.168.5.0/22 IP address block, which could support 210 hosts (32 – 22 = 10). Your ISP would set its routers so that any packets going to an address in that block would be sent to your network. Internally, your own routers might further subdivide this block of 1024 potential hosts into subnets, perhaps into four networks. Four networks require an additional two bits of addressing (22 = 4). You could set up your router to have four networks with this allocation: 192.168.5.0/24, 192.168.6.0/24, 192.168.7.0/24, and 192.168.8.0/24. Each of these networks could have 254 hosts. CIDR lets you arbitrarily divide networks and subnetworks into ever smaller blocks along the way. Each router has enough memory to keep track of the addresses it needs to direct and aggregates the rest. This scheme uses memory and address space efficiently. You could take 192.168.8.0/24 and further divided it into 16 networks with 14 hosts each. The 16 networks require four more bits (24 = 16), so you'd have 192.168.8.0/28, 192.168.8.16/28, 192.168.8.32/28, and so on to the last subnet of 192.168.8.240/16, which would have the hosts 192.168.8.241 through 192.168.8.254.Hostnames
People generally find it easier to work with symbolic names than with numbers, and GNU/Linux provides several ways to associate hostnames with IP addresses. The oldest method is to consult a list of names and addresses that are stored in the /etc/hosts file:$ cat /etc/hosts 127.0.0.1 localhost 220.127.116.11 gw–tcorp.tcorp.com gw–tcorp 18.104.22.168 bravo.tcorp.com bravo 22.214.171.124 hurrah.tcorp.com hurrah 126.96.36.199 kudos.tcorp.com kudos
The address 127.0.0.1 is reserved for the special hostname localhost, which serves as a hook for the system's networking software to operate on the local machine without going out onto a physical network. The names of the other systems are shown in two forms: in a fully qualified domain (FQDN) format that is meant to be unique and as a nickname that is unique locally but usually not unique over all the systems attached to the Internet.
As more hosts joined networks, storing these name-to-address mappings in a regular text file proved to be inefficient and inconvenient. The file grew ever larger and impossible to keep up-to-date. GNU/Linux supports NIS (Network Information Service, page 390) and NIS+, which were developed for use on Sun computers. Each of these network services stores information in a database. These solutions make it easier to find a specific address but are useful only for host information within a single administrative domain. Hosts outside the domain cannot access the information.
The solution is DNS (Domain Name Service, page 388). DNS effectively addresses the efficiency and update issues by arranging the entire network naming space as a hierarchy. Each domain in the DNS manages its own name space (addressing and name resolution), and each domain can easily query for any host or IP address by following the tree up or down the name space until the appropriate domain is found. By providing a hierarchical naming structure, DNS distributes name administration across the entire Internet.IPv6
The explosive growth of the Internet has uncovered deficiencies in the design of the current address plan, most notably lack of addresses. Over the next few years, a revised protocol, named IPng (IP Next Generation), or IPv6 (IP version 6),13 will be phased in (it may take longer; the phase-in is going quite slowly). This new scheme is designed to overcome the major limitations of the current approach and can be phased in gradually because it is compatible with the existing address usage. IPv6 makes it possible to assign many more unique Internet addresses (2128, or 340 undecillion ) and offers support for security and performance control features.
Enables autoconfiguration. With IPv4 autoconfiguration is available via optional DHCP. With IPv6 autoconfiguration is mandatory, making it easy for hosts to configure their IP addresses automatically.
Reserves 24 bits in the header for advanced services, such as resource reservation protocols, better backbone routing, and improved traffic engineering.
Makes multicast protocols mandatory and uses them extensively. In IPv4 multicast, which improves scalability, is optional.
Aggregates address blocks more efficiently because of the huge address space. This aggregation obsoletes NAT (page 1481), which decreased scalability and introduced protocol issues.
Provides a simplified packet header that allows hardware accelerators to work better.
A sample IPv6 address is fe80::a00:20ff:feff:5be2/10. Each group of four hexadecimal digits is equivalent to a number between 0 and 65536 (164). A pair of adjacent colons indicates a hex value of 0x0000, and leading 0s need not be shown. With eight sets of hexadecimal groupings, you have 65,5368 = 2128 possible addresses. In an IPv6 address on a host with the default autoconfiguration, the first characters in the address are always fe80. The last 64 bits hold an interface ID designation which is often the MAC address (page 1478) of the Ethernet controller on the system.
3COM [8 Certification Exam(s) ]
AccessData [1 Certification Exam(s) ]
ACFE [1 Certification Exam(s) ]
ACI [3 Certification Exam(s) ]
Acme-Packet [1 Certification Exam(s) ]
ACSM [4 Certification Exam(s) ]
ACT [1 Certification Exam(s) ]
Admission-Tests [13 Certification Exam(s) ]
ADOBE [93 Certification Exam(s) ]
AFP [1 Certification Exam(s) ]
AICPA [2 Certification Exam(s) ]
AIIM [1 Certification Exam(s) ]
Alcatel-Lucent [13 Certification Exam(s) ]
Alfresco [1 Certification Exam(s) ]
Altiris [3 Certification Exam(s) ]
Amazon [2 Certification Exam(s) ]
American-College [2 Certification Exam(s) ]
Android [4 Certification Exam(s) ]
APA [1 Certification Exam(s) ]
APC [2 Certification Exam(s) ]
APICS [2 Certification Exam(s) ]
Apple [69 Certification Exam(s) ]
AppSense [1 Certification Exam(s) ]
APTUSC [1 Certification Exam(s) ]
Arizona-Education [1 Certification Exam(s) ]
ARM [1 Certification Exam(s) ]
Aruba [6 Certification Exam(s) ]
ASIS [2 Certification Exam(s) ]
ASQ [3 Certification Exam(s) ]
ASTQB [8 Certification Exam(s) ]
Autodesk [2 Certification Exam(s) ]
Avaya [96 Certification Exam(s) ]
AXELOS [1 Certification Exam(s) ]
Axis [1 Certification Exam(s) ]
Banking [1 Certification Exam(s) ]
BEA [5 Certification Exam(s) ]
BICSI [2 Certification Exam(s) ]
BlackBerry [17 Certification Exam(s) ]
BlueCoat [2 Certification Exam(s) ]
Brocade [4 Certification Exam(s) ]
Business-Objects [11 Certification Exam(s) ]
Business-Tests [4 Certification Exam(s) ]
CA-Technologies [21 Certification Exam(s) ]
Certification-Board [10 Certification Exam(s) ]
Certiport [3 Certification Exam(s) ]
CheckPoint [41 Certification Exam(s) ]
CIDQ [1 Certification Exam(s) ]
CIPS [4 Certification Exam(s) ]
Cisco [318 Certification Exam(s) ]
Citrix [48 Certification Exam(s) ]
CIW [18 Certification Exam(s) ]
Cloudera [10 Certification Exam(s) ]
Cognos [19 Certification Exam(s) ]
College-Board [2 Certification Exam(s) ]
CompTIA [76 Certification Exam(s) ]
ComputerAssociates [6 Certification Exam(s) ]
Consultant [2 Certification Exam(s) ]
Counselor [4 Certification Exam(s) ]
CPP-Institue [2 Certification Exam(s) ]
CPP-Institute [1 Certification Exam(s) ]
CSP [1 Certification Exam(s) ]
CWNA [1 Certification Exam(s) ]
CWNP [13 Certification Exam(s) ]
Dassault [2 Certification Exam(s) ]
DELL [9 Certification Exam(s) ]
DMI [1 Certification Exam(s) ]
DRI [1 Certification Exam(s) ]
ECCouncil [21 Certification Exam(s) ]
ECDL [1 Certification Exam(s) ]
EMC [129 Certification Exam(s) ]
Enterasys [13 Certification Exam(s) ]
Ericsson [5 Certification Exam(s) ]
ESPA [1 Certification Exam(s) ]
Esri [2 Certification Exam(s) ]
ExamExpress [15 Certification Exam(s) ]
Exin [40 Certification Exam(s) ]
ExtremeNetworks [3 Certification Exam(s) ]
F5-Networks [20 Certification Exam(s) ]
FCTC [2 Certification Exam(s) ]
Filemaker [9 Certification Exam(s) ]
Financial [36 Certification Exam(s) ]
Food [4 Certification Exam(s) ]
Fortinet [13 Certification Exam(s) ]
Foundry [6 Certification Exam(s) ]
FSMTB [1 Certification Exam(s) ]
Fujitsu [2 Certification Exam(s) ]
GAQM [9 Certification Exam(s) ]
Genesys [4 Certification Exam(s) ]
GIAC [15 Certification Exam(s) ]
Google [4 Certification Exam(s) ]
GuidanceSoftware [2 Certification Exam(s) ]
H3C [1 Certification Exam(s) ]
HDI [9 Certification Exam(s) ]
Healthcare [3 Certification Exam(s) ]
HIPAA [2 Certification Exam(s) ]
Hitachi [30 Certification Exam(s) ]
Hortonworks [4 Certification Exam(s) ]
Hospitality [2 Certification Exam(s) ]
HP [750 Certification Exam(s) ]
HR [4 Certification Exam(s) ]
HRCI [1 Certification Exam(s) ]
Huawei [21 Certification Exam(s) ]
Hyperion [10 Certification Exam(s) ]
IAAP [1 Certification Exam(s) ]
IAHCSMM [1 Certification Exam(s) ]
IBM [1532 Certification Exam(s) ]
IBQH [1 Certification Exam(s) ]
ICAI [1 Certification Exam(s) ]
ICDL [6 Certification Exam(s) ]
IEEE [1 Certification Exam(s) ]
IELTS [1 Certification Exam(s) ]
IFPUG [1 Certification Exam(s) ]
IIA [3 Certification Exam(s) ]
IIBA [2 Certification Exam(s) ]
IISFA [1 Certification Exam(s) ]
Intel [2 Certification Exam(s) ]
IQN [1 Certification Exam(s) ]
IRS [1 Certification Exam(s) ]
ISA [1 Certification Exam(s) ]
ISACA [4 Certification Exam(s) ]
ISC2 [6 Certification Exam(s) ]
ISEB [24 Certification Exam(s) ]
Isilon [4 Certification Exam(s) ]
ISM [6 Certification Exam(s) ]
iSQI [7 Certification Exam(s) ]
ITEC [1 Certification Exam(s) ]
Juniper [64 Certification Exam(s) ]
LEED [1 Certification Exam(s) ]
Legato [5 Certification Exam(s) ]
Liferay [1 Certification Exam(s) ]
Logical-Operations [1 Certification Exam(s) ]
Lotus [66 Certification Exam(s) ]
LPI [24 Certification Exam(s) ]
LSI [3 Certification Exam(s) ]
Magento [3 Certification Exam(s) ]
Maintenance [2 Certification Exam(s) ]
McAfee [8 Certification Exam(s) ]
McData [3 Certification Exam(s) ]
Medical [69 Certification Exam(s) ]
Microsoft [374 Certification Exam(s) ]
Mile2 [3 Certification Exam(s) ]
Military [1 Certification Exam(s) ]
Misc [1 Certification Exam(s) ]
Motorola [7 Certification Exam(s) ]
mySQL [4 Certification Exam(s) ]
NBSTSA [1 Certification Exam(s) ]
NCEES [2 Certification Exam(s) ]
NCIDQ [1 Certification Exam(s) ]
NCLEX [2 Certification Exam(s) ]
Network-General [12 Certification Exam(s) ]
NetworkAppliance [39 Certification Exam(s) ]
NI [1 Certification Exam(s) ]
NIELIT [1 Certification Exam(s) ]
Nokia [6 Certification Exam(s) ]
Nortel [130 Certification Exam(s) ]
Novell [37 Certification Exam(s) ]
OMG [10 Certification Exam(s) ]
Oracle [279 Certification Exam(s) ]
P&C [2 Certification Exam(s) ]
Palo-Alto [4 Certification Exam(s) ]
PARCC [1 Certification Exam(s) ]
PayPal [1 Certification Exam(s) ]
Pegasystems [12 Certification Exam(s) ]
PEOPLECERT [4 Certification Exam(s) ]
PMI [15 Certification Exam(s) ]
Polycom [2 Certification Exam(s) ]
PostgreSQL-CE [1 Certification Exam(s) ]
Prince2 [6 Certification Exam(s) ]
PRMIA [1 Certification Exam(s) ]
PsychCorp [1 Certification Exam(s) ]
PTCB [2 Certification Exam(s) ]
QAI [1 Certification Exam(s) ]
QlikView [1 Certification Exam(s) ]
Quality-Assurance [7 Certification Exam(s) ]
RACC [1 Certification Exam(s) ]
Real-Estate [1 Certification Exam(s) ]
RedHat [8 Certification Exam(s) ]
RES [5 Certification Exam(s) ]
Riverbed [8 Certification Exam(s) ]
RSA [15 Certification Exam(s) ]
Sair [8 Certification Exam(s) ]
Salesforce [5 Certification Exam(s) ]
SANS [1 Certification Exam(s) ]
SAP [98 Certification Exam(s) ]
SASInstitute [15 Certification Exam(s) ]
SAT [1 Certification Exam(s) ]
SCO [10 Certification Exam(s) ]
SCP [6 Certification Exam(s) ]
SDI [3 Certification Exam(s) ]
See-Beyond [1 Certification Exam(s) ]
Siemens [1 Certification Exam(s) ]
Snia [7 Certification Exam(s) ]
SOA [15 Certification Exam(s) ]
Social-Work-Board [4 Certification Exam(s) ]
SpringSource [1 Certification Exam(s) ]
SUN [63 Certification Exam(s) ]
SUSE [1 Certification Exam(s) ]
Sybase [17 Certification Exam(s) ]
Symantec [134 Certification Exam(s) ]
Teacher-Certification [4 Certification Exam(s) ]
The-Open-Group [8 Certification Exam(s) ]
TIA [3 Certification Exam(s) ]
Tibco [18 Certification Exam(s) ]
Trainers [3 Certification Exam(s) ]
Trend [1 Certification Exam(s) ]
TruSecure [1 Certification Exam(s) ]
USMLE [1 Certification Exam(s) ]
VCE [6 Certification Exam(s) ]
Veeam [2 Certification Exam(s) ]
Veritas [33 Certification Exam(s) ]
Vmware [58 Certification Exam(s) ]
Wonderlic [2 Certification Exam(s) ]
Worldatwork [2 Certification Exam(s) ]
XML-Master [3 Certification Exam(s) ]
Zend [6 Certification Exam(s) ]
Dropmark : http://killexams.dropmark.com/367904/11587639
Wordpress : http://wp.me/p7SJ6L-TN
Issu : https://issuu.com/trutrainers/docs/920-331
Dropmark-Text : http://killexams.dropmark.com/367904/12128774
Blogspot : http://killexamsbraindump.blogspot.com/2017/11/dont-miss-these-nortel-920-331-dumps.html
RSS Feed : http://feeds.feedburner.com/Real920-331QuestionsThatAppearedInTestToday
weSRCH : https://www.wesrch.com/business/prpdfBU1HWO000MZHA
publitas.com : https://view.publitas.com/trutrainers-inc/once-you-memorize-these-920-331-q-a-you-will-get-100-marks
Calameo : http://en.calameo.com/books/00492352656297eb9c911
Box.net : https://app.box.com/s/mfr0v5ouobsfpwmr4jaixd7qb3esjgwe
zoho.com : https://docs.zoho.com/file/5ptno7ea7ba88ce4d4256ad9bedf7669599f1