Content

| 7.1 |  | Introduction to Cisco AVVID |
| 7.1.1 |  | Examining the Cisco AVVID framework |

Strategies for Convergence
With today's separate infrastructures, two strategic directions toward the convergence of data, voice, and video are possible.

One approach calls for the use of the PBX to support the kinds of interfaces and bandwidth required by today's IP-based data applications. This would mean interfaces such as Ethernet, Fast Ethernet, Gigabit Ethernet, and others on PBX platforms. Most data desktops are now connected at speeds of 10 or 100 Mbps, making this a strategy without merit. Fundamentally, the PBX is a time-division multiplexed system built on 64-kbps time slots with aggregate capacity in the tens of megabits per second. Although this is adequate for voice only, any attempt to drive data bandwidths shows that a whole new breed of platform would be required beyond the PBX.

It is also interesting to look back in history at other attempts to accomplish this integration. In the 1980s, when a 2400-bps modem was standard and a 9600-bps modem was almost unheard of, ISDN at 64 kbps per channel was being touted as the next high-speed desktop technology. Naturally this was well-suited to be terminated on the PBX, given its conformance to the bandwidth hierarchy of the PBX systems. Interestingly, this still did not take the marketplace by storm, even before technologies such as Ethernet were on the radar screen. Vendor investment in traditional PBX technology has not scaled to meet the demands of a converged network.

Most of the networking innovation during the last ten years has been developed around IP networks because of the pervasiveness and rapid development of the Internet. This includes World Wide Web technology, streaming video, IP telephony, higher-speed IP transport mechanisms, and more intelligence in the network to cope with new classes of delay-sensitive, mission-critical applications. This has all lead to the future of integrated networks, one where data, voice, and video share a common IP data network. Naturally, things will need to be done to prepare for this eventuality. The first step is to understand the architecture that will make this convergence a reality and some of the more specific considerations in the data networking infrastructure that will make this migration easier.

The Cisco AVVID Architecture
The Cisco solution for the convergence of data, voice, and video is called Cisco AVVID (Architecture for Voice, Video and Integrated Data). Cisco AVVID has three fundamental components:

- Clients are the user end stations or appliances that are used to communicate with the network or other users. Some examples are PCs, telephone devices, and video cameras.
- Applications for Cisco AVVID are written to an open-standards environment and, as such, will be supplied both by Cisco and third-party application developers. Some examples are interactive voice response (IVR), call center, and unified messaging.
- Infrastructure is the network upon which both the clients and applications reside. The network is IP-based using intelligence inherent in the platforms to provide the flexibility and scalability to support the convergence of different media. Examples of network devices are Catalyst switches, Cisco routers, and voice gateways.