Need to setup a SIP connection on a Cisco 7821

[Victor Savy]

I an trying to setup a new Cisco 7821 to use an existing external SIP account. The phone is ethernet connected to a standard domestic router. I had expected to be able to access admin settings on the phone via a browser on my PC, and enter sip user, password and server details, but if I browse to the ip address of the phone displayed on my router, I do not get a response. From web investigations, it seems I need to download an "MPP" version of the firmware and ftp that to the phone, but seemingly I have to first talk to the phone by licensed admin cisco software to tell it to allow the new firmware. I also seem to need a "PAK" (seemingly license related)  that I am not aware that I have.

1. Is it actually possible to get this not-inexpensive "IP phone" to work on a simple SIP VOIP account without buying costly admin software?

2. Does anyone have the detailed steps involved?

[Jonathan Schulenberg]

Convert between Enterprise Firmware and Multiplatform Firmware for Cisco IP Phone 7800 and 8800 Series Guide 

You’ll need to purchase the conversion license from an authorized reseller.

[Victor Savy]

Jonathan,

Many thanks, I will in first instance try and ger retailer to swap the phone for what I believe to be the correct model (7821-3PCC-K9)

Vic.

[Leo Laohoo]

The easy way is to convert the phone to 3PCC/MPP. 

Another method is to use the existing Enterprise image and integrate it to work with non-Cisco call managers.  The trick is to get a known working SEPmacaddress.cnf.xml file.  And one that is known to work with 78xx and 88xx can be found HERE.