# RTP switching limitations

When connecting two RTP sessions, consider the following limitations:

- At any given time, there can be only one source of voice data for the switch channel. That is, if the application switches two RTP endpoints that are both receiving voice from DS0 endpoints, it must disconnect one of the RTP endpoints from its associated DS0 endpoint. Otherwise, each RTP endpoint simultaneously receives voice data from two network sources.

- All RTP endpoints switched with switching channels must use the same encoding and decoding algorithm for processing voice data. The switching filter only forwards the packets from one RTP endpoint to another. It does not translate the data from one format to another.

- Each RTP endpoint can be connected to a maximum of 32 switch channels.

- When applications connect both an RTP switching channel and a duplex voice channel to the same RTP and DS0 endpoint, they must connect the duplex voice channel to the RTP endpoint first. RTP endpoints can support more than one RTP switching connection, but can support only one full duplex voice connection whether the connection consists of a single duplex voice channel or two simplex voice channels.