A15. Channelized T1 splits into 24 voice-grade channels, with each running at 64kbps. If you have a need for numerous local phones, it is much cheaper to get them delivered on T1 channels than as individual phone lines. Channelized T1 is developed and optimized for uncompressed voice communications. The channelized approach is required for access to the tradition PSTN. Unchannelized T1 provides you with 1.536Mbps (minus a framing bit), which you can split up anyway you choose. It is ideal for most data-communications applications, as well as compressed voice, video, and IP telephony. For example, you can split a leased T1 into 12 voice-grade channels to support 12 voice conversations, and then use the remaining 768kbps for either reasonably high-speed access to the Internet or for videoconferencing with your distant office. You can also compress voice to run at speeds of perhaps 8kbps or less by using IP telephone techniques and, therefore, put many more voice calls over a single T1 pi