Nortel Networks CTA 500dm manual Bearer Capabilities

Appendix 81

other authentication protocol is selected, the CTA 500dm will not be able to use MP and the call must be redialed using PPP.

Link Assumptions

For PPP and MP, it is assumed that the links are CRC-16 with

Maximum Receive Units (MRU) less than 1750 bytes.

For MP, it is assumed that call back is not required and that both links can be identically conÞgured.

Bearer Capabilities

The use of ISDN and digital networks allows a user to select a number of different bearer capabilities and data rates. Using a bearer capability gives the network information about how it should treat the call. In general, data cannot be sent over one of the voice bearer capabilities (3.1 kHz audio and speech). However, in some cases, especially on local calls, it may be possible to support 56 kbit/s and even 64 kbit/s data rates over voice calls. The CTA 500dm supports this capability.

To do this, your ISP must set up special dial-in phone numbers. Ask your ISP about this feature if you are using CTA 500dm where data calls are more expensive than voice calls.

P0873832 Issue 05 CTA 500dm On Line Guide