Cisco 7965 VoIP Phone with

By |August 4th, 2016|Categories: How To|Tags: , , , , |2 Comments

First you will need the SIP firmware for the phone, as they are supplied with SCCP firmware.
You can download a package I have built here. You can also download the latest version from the Cisco website, they are free and available with a standard Cisco website account.

You will also need a TFTP server that the phone can connect to, and if you do not force a TFTP server address into the phone your DHCP server will need to pass option 66 with the TFTP server IP address. Windows 2008 R2 DHCP options has this as 066 “Boot Server Host Name”.

Extract the zip file into your TFTP root directory and then edit the SEP#######.cnf.xml file, search for the word “FIXME” and read around those lines to fix and replace for your setup. Then rename the file to be the MAC address of the phone. Replace ######### with the MAC as the sample file has already.

You may wish to also edit the dialplan.xml file and set your area codes and other stuff.

The phone will boot up on the network, grab an IP address from your DHCP server, pull the TFTP server address from the DHCP options and then contact the TFTP server. It will pull the SEP#######.cnf.xml file that responds to the phones MAC address. After some reboots and firmware changes it should register to your SIP provider.

I have this all working for If you are behind a firewall you may have issues with NAT. I am using pfSense and have no issues. The phone has NAT turned off (in the config already) and settings for the sub-account I am using has NAT set to ‘yes’.

Lots of info was found on the voip-info website.


  1. Nick October 7, 2017 at 1:19 PM - Reply


    Just came across your article as I’m trying to get a Cisco 7965 working on One question: do you have any SIP-specific modules loaded into your pfSense setup, or just basic NAT? I seem to be having NAT-related issues using a Linux Vyatta firewall (IPtables-based).


    • zharvek October 7, 2017 at 9:26 PM - Reply

      I do have some custom NAT policies setup.
      Interface: WAN, Source: Subnet/24, Source Port: tcp/*, Dest: *, Dest Port: tcp/5060, NAT Addr: WAN Addr, NAT Port: *, Static Port: No
      Interface: WAN, Source: Subnet/24, Source Port: udp/*, Dest: *, Dest Port: udp/16384:16391, NAT Addr: WAN Addr, NAT Port: *, Static Port: No

      That is all I have setup and I’ve yet to have any NAT issues. I have Cisco IP phones with SIP firmware. Three registered all the time.

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