Architecture

Client Server vs P2P for the Enterprise

Efficient, optimized software doesn't require the large investment in heavy iron. A "server" program running on a modern laptop can host 60 users in any combination of conferences. This same server is efficient enough to embed in a PDA, but that's another page (see Palantir).

Client Server:

Client-server is the ideal architecture for enterprise communication and collaboration tools. This is because the bandwidth at each client is constant, and overall network bandwidth is C * N, where C is the bandwidth of the codec being used and N is the number of users. A server approach allows the enterprise to have some control over Quality of Service (QoS), as well as accounts to access the system.

Most importantly, a server architecture provides certain features. Central to DiamondWare's solutions is the ability to participate in several conferences at the same time. What about presence information when a user's computer is turned off? A server can provide "on vacation until Jan 10". A server also allows someone to set up voice colorization properly for the various teams in a conference, and all users share these settings.

Finally, a central server can be set up to record and monitor voice and text activity, and backed up. It integrates more cleanly with enterprise telephony infrastructure such as T1s and IP PBXs. And of course a central server can be deployed to support larger conferences.

P2P Peer to Peer Approach: P2P, on the other hand, can be connected in two ways. The first method imposes C * (N - 1) bandwidth on each peer, and worse yet it uses C * ((N * (N - 1)) / 2) total network bandwidth!

The second architecture allows for a hodgepodge of connectivity, wherein each peer acts as a temporary mini-server. This model can approach the client-server model, but it can also take on a different shape: the daisy-chain. The downside to the chain is that latency accumulates from one end to the other. Not only will this make conversation awkward and half-duplex, but different users will experience different latencies for each other user. The entire conference will be out of sync.

Of course, both P2P variants lack central accounting control, presence information for offline users, multiconferencing, project situation rooms, etc.