Configuring CME for SIP to Allow Phones to Register
The command set using SIP is actually quite similar to SCCP - there are some subtle differences, mainly to do with entering the CME sub-configuration mode(s). This article considers the minimum steps to configure 2 x IP phones and enable calling from Phone A to Phone B.
Firstly, allow calls from SIP to SIP endpoints, and setup the SIP registrar.
voice service voip
  allow-connections sip to sip
  sip
   registrar server expires max 1200 min 300
Next, configure the global parameters; at a minimum, the following must be configured:
- Mode (CME)
- Maximum DN's (based on hardware platform - i.e. 192 in a 2821)
- Maximum pool, or IP phones (again, based on hardware platform)
- Specify a load for each phone type that shall be installed
- Specify the default path for TFTP configuration files
- Create profile (equivalent to "create cnf" when using SCCP)
voice register global
 mode cme
 source-address 172.16.1.1 port 5060
 load 7941 term41.default
 tftp-path flash:
 create profile
Now we must configure the directory numbers to be assigned to the IP phones.
voice register dn 1
 number 1000
 name Phone1
 label Phone1: 1000
 mwi
Finally, configure the IP phones.
voice register pool 1
 id mac 001B.D4A0.9BA0
 type 7941
 number 1 dn 1
 dtmf-relay sip-notify
 username user1 password cisco
 codec g711ulaw
Verify configuration of SIP CME using show voice register global:
VOICE REGISTER GLOBAL
=====================
CONFIG [Version=7.0(1)]
========================
  Version 7.0(1)
  Mode is cme
  Max-pool is 58
  Max-dn is 192
  Outbound-proxy is enabled and will use global configured value
  Source-address is 172.16.1.1 port 5060
  Load 7941 is term41.default
  Load 7961 is term61.default
  Authenticate register
  Authenticate realm cisco.com
  Time-format is 12
  Date-format is D/M/Y
  Time-zone is 5
  Hold-alert is disabled
  Mwi stutter is disabled
  Mwi registration for full E.164 is disabled
  Forwarding local is enabled
  Dst auto adjust is enabled
    start at Apr week 1 day Sun time 02:00
    stop at Oct week 8 day Sun time 02:00
  Call List BLF is enabled
  Max redirect number is 5
  Telnet Level: 0
  Tftp path is flash:
  Generate text file is disabled
  Tftp files are created, current syncinfo 0005437241220141
  OS79XX.TXT is not created
  timeout interdigit 10
  network-locale[0] US (This is the default network locale for this box)
  network-locale[1] US
  network-locale[2] US
  network-locale[3] US
  network-locale[4] US
  user-locale[0] US (This is the default user locale for this box)
  user-locale[1] US
  user-locale[2] US
  user-locale[3] US
  user-locale[4] US
And, finally, confirm that the IP phone is registered.
VOICE REGISTER POOL
===================
Pool Tag 1
Config:
  Mac address is 001B.D4A0.9BA0
  Type is 7941
  Number list 1 : DN 1
  Proxy Ip address is 0.0.0.0
  DTMF Relay is enabled, sip-notify
  Call Waiting is enabled
  DnD is disabled
  keep-conference is enabled
  username user1 password cisco
  kpml signal is enabled
  Transport type is udp
  service-control mechanism is not supported
  registration Call ID is 001bd4a0-9ba00005-9d8cbda4-b141937e@192.168.254.2
  active primary line is: 1000
  contact IP address: 192.168.254.2 port 5060
Dialpeers created:
dial-peer voice 40001 voip
 destination-pattern 1000
 session target ipv4:192.168.254.2:5060
 session protocol sipv2
 dtmf-relay sip-notify
 digit collect kpml
 codec g711ulaw bytes 160
  after-hours-exempt FALSE
Statistics:
  Active registrations : 2
  Total SIP phones registered: 1
  Total Registration Statistics
    Registration requests : 2
    Registration success : 2
    Registration failed : 0
    unRegister requests : 0
    unRegister success : 0
    unRegister failed : 0
