MGCP study notes


Client server voice signaling protocol which separates:
– call control: handled my call agent
– media translation: handled by voice gateway

2 versions
v 0.1 (default)
v 1.0 industry standard

Why use MGCP:-
1. Centralised Management
2. simple or uninteligent gateway configuration
3. For MGCP backhaul QSIG configuration

MGCP Messages
1. Router establishes TCP Session (port 2427) to ccm
2. CCM Audits (AUEP) and Registers (RQNT) configured endpooints
3. ccm now controls the end points using a series of MCP commands

Common MGCP Messages
– Create Connection (CRCX)
– Notification request (RQNT)
– Notify (NTFY)
– Modify Connection (MDCX)
– Delete connection (DLCX)
– Audit endpoint (AUEP)
– Endpoint config (EPCF)
– RestartinProgress (RSIP)

Call flow
1. local phone goes off hook (NTFY/RQNT)
2. Phone Dials Digits (NTFY)
3. Connection Created (CRCX/ACK)
4. ..mdcx..Ringback and Ringing request (RQNT)
5. remote phone goes off hook (NTFY)
6. Gateway begin 2way communication (MDCX)
7. Local phone hangs up (NTFY)
8. Gateway disconnects call (DLCX)

MGCP backhaul allows l3 control to be forwarded to CUCM


1.requires dial-peer config (place port under MGCP control)
2. dont forget STST Strategies

Foundation setup
# sh voice port summ
# mgcp
# mgcp call-agent service type mgcp version 1.0
# ccm-manager mgcp
# ccm-manager redundant host

Dial-peer config
#dial-peer voice 200 pots
#port 0/0/0
#service MGCPAPP

MGCP Fallback
router to fall back to another config if MGCP application fails
###service alternate default
+ h.323
TFTP Config
#ccm-manager config server
#ccm-manager config

BRI/PRI backhaul
show controllers
controller t1 1/1
pri-time slots 1-24 service mgcp

int s0/0/0:23
isdn bind-l3 ccm-manager

dtmf relay
mgcp dtmf-relay all mode out-or-band


sh ccm-manager
show mgcp – dump
show mgcp endpoint
show voice port
sho mgcp connection


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