Network Connectivity

Most contemporary wired networks comprise of packet switches which can support huge amounts of traffic.

Typically the wired network capacity is not an area of concern when deploying a VoIP solution. However, many large deployments are spread across geographically disperse areas, and these utilize Wide Area Networks. When deploying a WAN, the bandwidth requirements for VoIP traffic and end to end latency become critical to the success of the deployment.

If you are planning to allow Vocera over a WAN, keep in mind that authentication can add considerable delays to network traffic.

The bandwidth requirement for your wired infrastructure increases linearly as the number of badges simultaneously transmitting increase. Vocera has calculated the theoretical maximum bandwidth requirement for simultaneous badge transmissions as follows. The actual requirement in any given deployment may differ.

Table 1. Maximum bandwidth requirements
Number of Simultaneous Calls or Genie Sessions (Full Duplex)	Maximum Bandwidth Required
50	8 Mbps
100	16 Mbps
150	24 Mbps
350	56 Mbps

Also, the total one-way latency of the circuit, including all network propagation and serialization delays, must not exceed 150 ms.

Important: Network capacity planning must take into account the duration of Vocera calls, the total number of Vocera devices deployed, the statistical likelihood of simultaneous transmissions, and other usage issues, similar to Erlang calculations prepared for PBXs.

Most Vocera calls typically have a short duration (under 30 seconds). In a deployment with 500 total Vocera devices, the statistical likelihood of all of them being involved in simultaneous device-to-device calls (250 simultaneous transmissions) may be fairly small.