Yes you would need to upload a SIP firmware and then generate a XML file. You will need support contract to download the SIP firmware from Cisco. If you are planning to use the phone with Asterisk, then you dont need a CUCM server.
It may not be very straightforward, go through the below documents if they are of any help:
http://www.voip-info.org/wiki/view/Asterisk%20phone%20cisco%2079xx
http://www.minded.ca/2009-12-16/configure-cisco-ip-phones-with-asterisk/
http://www.juliandunn.net/2006/05/25/connecting-a-cisco-7960-ip-phone-to-asterisk/
-Terry
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