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Cisco AVVID and IP Telephony Design & Implementation Fast Track • Appendix 443 Benefiting from Digital Systems ; Digital signals are binary, made up of on or off signals. ; Digital signals can be compressed, corrected, and manipulated more easily than analog signals. ; Amplification can occur in digital signals without amplifying background noise and static. Providing Video Services ; Video services can demand the most real-time bandwidth in the network. ; Video data is typically compressed to reduce its load on the network. ; One-to-many video is a perfect application for IP multicast. ❖ Chapter 2: New World Technologies Introduction to IP Telephony ; Simplified administration is achieved by converging three separate networks into one, allowing one resource pool to administer the entire network. ; Toll bypass allows organizations to avoid costly telecommunications expenses by utilizing the data infrastructure. ; Unified messaging combines voice-mail, e-mail, and faxes into one easy-to- use interface. IP Telephony Components ; CallManager provides the IP telephony network with a software-based PBX system. ; IP telephones provide the user interface to the IP telephony network. ; Gateways provide the interface between the IP telephony network and the public switched telephone network (PSTN) or a legacy PBX device. www.syngress.com Chapter 1 Continued 109_AVVID_DI_AppFT 10/10/01 1:59 PM Page 443 444 Appendix • Cisco AVVID and IP Telephony Design & Implementation Fast Track Exploring IP Telephony Applications ; WebAttendant replaces the traditional PBX attendant console. ; IP SoftPhone provides a software-based IP telephone handset. ; Third-party applications include software from Interactive Intelligence, Latitude, and ISI. Introduction to Video ; Traditional video-conferencing utilizes ISDN lines in a point-to-point infrastructure. ; IP-based video-conferencing utilizes the H.323 specification allowing for video-conferencing over a variety of mediums. ; IP-based video-conferencing is much more efficient than traditional video- conferencing because the existing data infrastructure is utilized opposed to a separate infrastructure. ; Gateways provide access to the outside world from your internal network. ; Gatekeepers are used to permit or deny requests for video conferences. ; Multi-point control units (MCU) serve as a center for video-conferencing communications and infrastructure. Enhancing Network Infrastructure ; Routers provide gateway services and voice aggregation for IP telephony by use of analog ports, FXO, FXS, E&M as well as digital trunking cards. ; Routers that support IP telephony include the 1751, 2600 Series, 3600 Series, and 7200 Series. ; Switches that support inline power modules include the 3524XL-PWR, 6000 Series, and 4000 Series. ; Inline power is also provided by using the Catalyst inline power patch panel. What Does the Future Hold? ; Future revisions on CallManager include a call center solution. www.syngress.com Chapter 2 Continued 109_AVVID_DI_AppFT 10/10/01 1:59 PM Page 444 Cisco AVVID and IP Telephony Design & Implementation Fast Track • Appendix 445 ; Pizza box and integrated access devices will provide all-in-one functionality for branch offices. ; IOS-based versions of CallManager will further develop. ❖ Chapter 3: AVVID Gateway Selection Introduction to AVVID Gateways ; In the Cisco AVVID world, there are voice and video gateways to provide connectivity to legacy networks. Cisco has voice gateways, which are standalone routers, IOS-based routers, and Catalyst switch-based routers. ; The standalone gateways include the DT-24+, DE-30+, and VG200. Router IOS-based gateway solutions are the 175x, 2600, 3600, 3810, 5300, 7200, and 7500.The switch-based gateways are the Catalyst 4000, 4200, and 6000 Series.These gateways run the following protocols: H.323, MGCP, Skinny, and SIP. ; The IP/VC 3500 family is the videoconferencing gateway products from Cisco. Understanding the Capabilities of Gateway Protocols ; H.323 is the most supported gateway protocol, backed by the Cisco 1750, 2600, 3600, AS5300, 7200, and 7500 Series routers. ; Skinny Station Protocol allows a Skinny client to use TCP/IP to transmit and receive calls as with DT-24+, DE-30+, and VG200. ; MGCP is a master/slave protocol, where the gateway is the slave servicing commands from the master, which is the call agent.The MGCP protocol functions in an environment where the call control intelligence have been removed from the gateway. ; Session Initiation Protocol (SIP) is an application layer control protocol that can establish, modify, and terminate multimedia sessions or calls. www.syngress.com Chapter 2 Continued 109_AVVID_DI_AppFT 10/10/01 1:59 PM Page 445 446 Appendix • Cisco AVVID and IP Telephony Design & Implementation Fast Track Choosing a Voice Gateway Solution ; Determining the right voice gateway solutions will depend on a number of factors, from the size and scale of the organization to the budget. ; Solutions from a switch point-of-view would include, the Catalyst 4000, 4224/4248, and 6000 family. If you wish to use routers, you should choose from the following: the 1750, 2600, 3600, 3810, 7200, and 7500 Series. Access servers may be best in some instances, including the AS5300, the AS5400, and the AS5800. Cisco DT-24, DE-30, and VG-200 would suffice for standalone protocol solutions. ; For small- to mid-sized companies looking for a nice all-in-one solution, the ICS 7750, deployed with a Catalyst 3524XL-PWR switch and Cisco IP phones, would do wonderfully. ; The DPA 7610/7630 Voice Mail Gateway would be another important element of an AVVID solution. It provides a gateway allowing legacy voice mail systems to communicate with Cisco CallManagers. Choosing a Video Gateway Solution ; Cisco’s family of video gateway solutions can satisfy everyone from the small 40-person organization to those with 4000 employees. ; The IP/VC 3510 MCU connects three or more H.323 videoconference endpoints into a single multiparticipant meeting and is able to support ad- hoc or scheduled videoconferences. Participants can join by having the MCU dial to them or by using the Web interface. ; IP/VC 3520 and 3525 gateways provide the translation services between H.320 and H.323 networks.This system allows users to conduct videoconferencing across the IP LAN, or via the PSTN.The IP/VC 352x series gateways support V.35, ISDN BRI, and ISDN PRI interfaces. IP/VC 3530 VTA translates from a H.320 ISDN-based system to a H.323 IP-based network.The IP/VC 3540 solution is a highly scalable MCU, which is chassis-based and expands to up to three modules.These modules come in 30-, 60-, and 100-user versions. www.syngress.com Chapter 3 Continued 109_AVVID_DI_AppFT 10/10/01 1:59 PM Page 446 Cisco AVVID and IP Telephony Design & Implementation Fast Track • Appendix 447 Multimedia Conference Manager Services ; Multimedia Conference Manager (MCM) works in conjunction with Cisco’s IP/VC products, and services a H.323 gatekeeper and proxy. ; MCM is a part of the Cisco IOS for the following router platforms: 2500, 2600, 3600, 3810, and 7200. ; The MCM gatekeeper functions include: zone administration, RAS,AAA services, bandwidth management, session management, and call accounting. The proxy service provides QoS capabilities to the videoconferencing sessions. ❖ Chapter 4: AVVID Clustering CallManager Clustering ; Cisco AVVID infrastructure includes a variety of features to facilitate load balancing, scalability, and redundancy for IP telephony and multimedia conference solutions. ; Cisco CallManager clusters are used to improve the scalability and reliability of Cisco IP telephony solutions. ; Multipoint Control Unit cascading is used to improve the scalability of voice/video conferencing. ; A maximum of eight Cisco CallManagers can be members of a cluster, with as many as six used for call processing. ; The possible roles of servers within a cluster are: database publisher server, TFTP server, application server, primary call-processing server, and backup call-processing server. ; Intra-cluster communications rely on high-speed network connections, and are not supported across WANs. ; The CallManager database contains the configuration of all IP telephony devices. ; Real-time data replicated between servers in a cluster consists of registration information of IP telephony devices. ; Many CallManager features do not function between different clusters. www.syngress.com Chapter 3 Continued 109_AVVID_DI_AppFT 10/10/01 1:59 PM Page 447 448 Appendix • Cisco AVVID and IP Telephony Design & Implementation Fast Track ; Database redundancy is achieved by replicating the publisher database to all servers within a cluster. ; Redundancy groups facilitate server failover.A device is associated with a redundancy group, which is a list of up to three servers. If the primary server fails, call processing is transferred to the secondary server. ; Balanced call processing can be achieved by assigning different primary servers to different groups of devices. ; Device weights are used to calculate the maximum number of devices that can be supported by a single CallManager server. Video Clustering ; A maximum of 15 conference participants can be supported by a single MCU. ; Two or more MCUs can be cascaded to support larger conferences. ; Conference participants are unaware of the cascaded nature of the conference. ; Only a single voice/video data stream exists between cascaded MCUs. ; Voice/video traffic can be localized by correctly dispersing MCUs across a network. ; The number of MCUs that can be cascaded together depends on available bandwidth. ; To invite a MCU to join a conference from a terminal, dial the host conference password, the invite code **, followed by the conference password of the invited MCU. ❖ Chapter 5: Voice and Video Gatekeeper Design Understanding Gatekeeper Basics ; A gatekeeper is a central point of control for an H.323 (voice and video) network. www.syngress.com Chapter 4 Continued 109_AVVID_DI_AppFT 10/10/01 1:59 PM Page 448 Cisco AVVID and IP Telephony Design & Implementation Fast Track • Appendix 449 ; Gatekeepers usually use E.164 addressing (telephone numbers) for identifying endpoints and routing calls within a network. ; Gatekeepers run an H.323/MCM feature set IOS on many common Cisco routers. A Gatekeeper’s Role in Voice and Video Networking ; Gatekeepers manage one or multiple zones and permit or reject calls into or out of each zone. ; Gatekeepers can provide accounting information for calls, such as length of call, time of call, number called, and so on. ; Cisco’s Multimedia Conference Manager (MCM) can act as a proxy for increased security and QoS as well as a gatekeeper. ; Video gatekeepers can be embedded in the video controller or can be an MCM. ; Video gatekeepers interface with gateways for off-network calls, such as ISDN videoconferences. ; Gatekeepers monitor (and limit) bandwidth usage to assure existing calls receive high quality. ❖ Chapter 6: DSPs Explained DSP Provisioning ; The Cisco DSP module is a Texas Instruments model C542 and C549 72- pin SIMM.These DSPs work with two levels of CODEC complexity: medium and high. ; The medium-complexity CODECs that work with the Cisco DSP are G.711 (a-law and µ-law), G.726, G.729a, G.729ab, and Fax-relay.The high- complexity CODECs include the G.728, G.723, G.729, G.729b, and Fax-relay. ; The DSP resources are used for conference bridging and transcoding. www.syngress.com Chapter 5 Continued 109_AVVID_DI_AppFT 10/10/01 1:59 PM Page 449 450 Appendix • Cisco AVVID and IP Telephony Design & Implementation Fast Track Conferencing and Transcoding ; Conferencing is the process of joining multiple callers into a single multiway call.The two types of multiparticipant voice calls supported by the Cisco CallManager are ad-hoc and meet-me. ; DSP resources are used in the conference bridge scenario to convert VoIP calls into TDM streams and sum them into a single call. ; Transcoding is the process of converting IP packets of voice streams between a low bit-rate (LBR) CODEC to G.711.Transcoding functions can be done by converting G.723 and G.729 CODECs to G.711. ; Conferencing and transcoding is performed either by hardware or software. The software version is performed on a Cisco CallManager server, while the hardware solutions are the Catalyst 4000 AGM module, Catalyst 6000 8-port T1/E1Voice and Services module, and NM-HDV module. Catalyst 4000 Modules ; The Catalyst 4000 Access Gateway Module (AGM) provides voice network services to the Catalyst 4000 switch,VoIP IP WAN routing, and an IP telephony mode for use with a voice gateway.The Catalyst 4000 AGM supports voice interface cards (VICs) and WAN interface cards (WICs) from the 1600/1700/2600/3600 Series routers. Catalyst 6000 Modules ; The Catalyst 6000 switch module features an 8-port Voice T1/E1 and Services module,WS-X6608-E1 or WS-X6608-T1. ; The Voice T1/E1 module supports T1/E1 CCS signaling, ISDN PRI network, and user-side signaling. Similar to the AGM module for the Catalyst 4000, the Voice T1/E1 can be provisioned for conferencing and transcoding.The Voice T1/E1 can do mixed CODEC conferencing, whereas the AGM only does G.711 conferencing with individual DSP resources. NM-HDV Modules ; The biggest benefit of this module is PBX leased line replacement and toll bypass, meaning that a company’s long distance expenses can all but be www.syngress.com Chapter 6 Continued 109_AVVID_DI_AppFT 10/10/01 1:59 PM Page 450 Cisco AVVID and IP Telephony Design & Implementation Fast Track • Appendix 451 eliminated. Platform support includes VG200, 2600, 3600, and Catalyst AGM E1 Models (medium complexity involving NM-HDV-1E1-12, NM-HDV- 1E1-30, and NM-HDV-2E1-60).With E1 Models (high complexity M- HDV-1E1-30E), or T1 Models, and medium complexity (NM-HDV-1T1- 12, NM-HDV-1T1-24, and NM-HDV-2T1-48) supported, it will also support T1 Models (high complexity NM-HDV-1T1-24E). Sample Design Scenarios ; When designing your DSP provisioning, you must take into account the number of users, the type of applications using different CODEC, and the overall IP telephony design to determine which solution best fits your needs, whether it’s using the CallManager itself or one of the Catalyst switches. ; The branch office environment is an excellent candidate for the Catalyst 4000 switch with an Access Gateway module (AGM).This solution can provide 10/100/1000 Ethernet switching with inline power for IP phones, PSTN connectivity, IP routing, and also serve as a DSP resource.The DSP resources provide conferencing and transcoding services for your user population. ; The enterprise campus has higher scalability requirements than the branch office.With this in mind, you should consider the Catalyst 6000 with the 8-port T1/E1 Voice and Service module as a good fit for the needs of this environment. ❖ Chapter 7: AVVID Applications Creating Customer Contact Solutions ; Make sure you understand the customer’s needs. ; Provide the client with the solution that best suits these needs. ; Make sure to stay within the Cisco recommended guidelines. ; With the IP contact center, there are many different components. Make sure the version numbers needed to run the solution are all compatible. www.syngress.com Chapter 6 Continued 109_AVVID_DI_AppFT 10/10/01 1:59 PM Page 451 452 Appendix • Cisco AVVID and IP Telephony Design & Implementation Fast Track Providing Voice Recording Options ; Make sure the infrastructure can support voice recording. ; Define the endpoints that need to be recorded, and implement a policy using this as a framework. Call Accounting, Billing, and Network Management Solutions ; Understand the requirements in enabling CDRs throughout your network, not just on the Cisco CallManager, but also on your router infrastructure (if possible). ; Look at the Administrative Reporting Tool (ART) with Cisco CallManager to decide whether this would provide you with the information needed before looking at external solutions. ; Define the information needed with your reports, and based on this, look for solutions that meet the requirement you and your customers have. Designing Voice and Unified Messaging Solutions ; Decide on the version of Unity needed. ; If upgrading from voice mail to unified messaging, do not forget the possible hardware requirements. ; You should be running Microsoft Exchange 5.5 or Exchange 2000, with future support for other platforms. Understanding Other Voice Applications ; Keep it as simple as possible, if services or applications are not needed, do not enable them. It complicates the configuration. ; IP Automated Attendant (AA) is extremely useful in large organizations where switchboard operators are normally overworked. Automated Attendant, as its name suggests, provides automated functions an attendant might normally perform. www.syngress.com Chapter 7 Continued 109_AVVID_DI_AppFT 10/10/01 1:59 PM Page 452 [...]... devices through, 32–33 feature transparency and, 103 groups and, 33 inter-cluster communications, 104 , 105 106 intra-cluster communications, 104 105 LANs and, 403–404, 419–420 limitations of, 34 multiple clusters and, 105 106 , 113–115, 122 redundancy and, 103 , 106 107 , 123 resiliency and, 103 roles of server in cluster, 33 scalability and, 102 , 103 WebAttendant and, 42 clustering, gatekeeper, 137 clustering,... 112–113 case study of, 119–124 Cisco recommendations for, 108 – 110 471 device weights and, 110 112 multiple CallManager clusters, 113–115 clustering, CallManager, 32–34, 102 –115, 317 balanced call processing and, 108 , 109 benefits of, 103 CallManager roles within cluster, 102 103 campus clustering, 112–113 case study of, 119–124 cluster design and, 33–34, 108 –115 configuration checklist for, 114 configuration... self-redundancy and, 5–6 in-band signaling and, 11 three tier model of, 5 wiring requirements, 12 database publisher servers, 33, 103 database redundancy, clustering and, 103 , 106 107 DE-30+, 39, 68, 70, 71, 83–84 protocols supported by, 72 SSP and, 31 109 _AVVID_DI_index 10/ 10/01 3:19 PM Page 473 Index debug mgcp all command, 364, 415 dense mode, PIM, 425–426 destination-pattern command, 303–304 destination... dial peers and, 303–304 verification of, 314–315 CallManager Publisher, 104 CallManager redundancy groups, 106 107 balanced call processing and, 108 , 109 recommended configuration for, 108 – 110 campus-wide clustering, 112–113 CAS See channel associated signaling (CAS) CAS E1 signaling protocol, 82 CAS T1 signaling protocol, 82 109 _AVVID_DI_index 10/ 10/01 3:19 PM Page 469 Index cascading, 102 , 117–119... H.323 networks and E.164 numbers and, 141–142, 148 gatekeepers and, 135, 148–151 H.323 IDs and, 141–142, 148 call routing, PBX systems and, 15 call processing and, 8–9 international calls and, 10 11 call transformations, enterprise dial plans and, 408 CallDetailRecord database, 209 CallDetailRecord Diagnostic database, 209 called party transformation, 301–302 109 _AVVID_DI_index 468 10/ 10/01 3:19 PM... static and amplification in analog waveform and, 16, 17 analog signals, 16, 17 analog voice interfaces, Cisco router, 50–52 ear -and- mouth (E&M), 13, 51, 69, 342 Foreign Exchange Office (FXO), 51, 15–16, 69, 342, 343 Foreign Exchange Station (FXS), 7, 51, 15, 69, 342 analog VoIP gateways, 69, 70 CallManager support of, 30 Catalyst 4000 Access Gateway module, 70, 85, 86 465 109 _AVVID_DI_index 466 10/ 10/01... 463 109 _AVVID_DI_AppFT 464 10/ 10/01 1:59 PM Page 464 Appendix • Cisco AVVID and IP Telephony Design & Implementation Fast Track Chapter 11 Continued It also allows for remote mentoring of personnel without having associated travel costs AVVID applications can provide interactive and automated customer support solutions, such as chat and whiteboarding solutions www.syngress.com 109 _AVVID_DI_index 10/ 10/01... clustering and, 108 , 109 bandwidth allocation of by LLQ, 245–246 configuring zone, 160–161 controlling with gatekeepers, 134, 322 limiting with gatekeepers, 135, 142–143 bandwidth command, 160, 245 Basic Rate Interface (BRI) channels, 19 Bc See committed burst size (Bc), frame relay and Be See excess burst size (Be), frame relay and BECN See backwards explicit congestion notification (BECN) Bell, Alexander... 31–32 redundancy of, 72, 415 regions and, 361 route recovery and, 409– 410 SNMP registration and, 36 software-based conferencing and transcoding, 171 SSP and, 31 Trivial File Transfer Protocol (TFTP) servers, 33 troubleshooting, 364–365 version 2.x, 30, 32 version 3.x, 30, 32 VoIP voice recording and, 205–208 WebAttendant and, 29, 41–42, 215 CallManager Administrator, 104 CallManager dial plans configuration... 290–291 character representations and, 291 session targets and, 292 device controls, CallManager, 355 device pools, 107 , 108 , 109 , 361 device weights, CallManager and, 110 112, 121–122, 196 DHCP server, CallManager configuration, 358–359 dial groups, partitioning of, 307–309 dial-peer terminator command, 304 dial peers, 282, 283 configuration of for outbound and inbound calls, 290–292 . modules.These modules come in 30-, 60-, and 100 -user versions. www.syngress.com Chapter 3 Continued 109 _AVVID_DI_AppFT 10/ 10/01 1:59 PM Page 446 Cisco AVVID and IP Telephony Design & Implementation Fast. establish, modify, and terminate multimedia sessions or calls. www.syngress.com Chapter 2 Continued 109 _AVVID_DI_AppFT 10/ 10/01 1:59 PM Page 445 446 Appendix • Cisco AVVID and IP Telephony Design &. solution. www.syngress.com Chapter 2 Continued 109 _AVVID_DI_AppFT 10/ 10/01 1:59 PM Page 444 Cisco AVVID and IP Telephony Design & Implementation Fast Track • Appendix 445 ; Pizza box and integrated access devices