Need help to register cisco CP-6941 / CP-8941 with Asterisk


I am trying to connect cisco CP-6941/CP-8941 with Asterisk server, however I am not able to connect any of these IP phones with Asterisk.

I have loaded the SIP firmware on these devices and created SIPDefault.cnf file in TFTP root directory. However they are not trying to download this config file.

Looking for the following information –

  1. Does these phone compatible with Asterisk server ?
  2. how to set the SIP configuration (Asterisk server Ip, userid etc) on these phones ?

Setup details:
Asterisk – Asterisk 11.7.0
CISCO IP Phones – CP-6941 and CP-8941