|
A T1 is considered full, when it is either a channelized T1 with all 24 timeslots occupied by voice or data services, or when the T1 carries a single non-channelized service at 1.544Mhz. A full T1 is a powerful T1 line. Channelized service refers to up to 24 DS0 circuits (of any service type) combined together (multiplexed) for transport via T1 (DS1) service. This can be any combination of voice and/or data services that utilize all 24 timeslots on the T1 facility and are typically for access purposes, not long-haul transport. Channelized full T1 line access services gained popularity in the late 1980s when the cost of a T1 access facility equaled approximately 8 DS0 access loops. Any more DS0-level services could be added (up to 24 DS0s) to further contribute to access cost reductions. From a Telco perspective, since a T1 requires 2 copper pairs and a DDS 56kb/64kb requires 2 pairs as well, Telcos were enticing customers to move to higher speed access services for two reasons. 1) Limit further installation of customer-ended copper pairs, and 2) Combine services together onto a single access T1 to make it easier to retain the business. Non-Channelized service refers to the T1 carrying a single service of 1.544Mhz. This service is typically a data service, either for point-to-point connectivity, ISP access, Frame Relay data access, or similar. The key factor here is that the lowest common "service" is running at T1 (DS1) speeds, and is not a combination of multiple lower speed services multiplexed up to T1 speeds (as in Channelized service above). Please see our multiplexing page for an in-depth tutorial about multiplexing schemes. |
Full T1
