© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-1
Implementing VoIP Gateways
Implementing MGCP Gateways
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-2
MGCP Components
Defined in RFC 3435 which obsoletes RFC 2705
Architecture and requirements defined in RFC 2805
Centralized device control with simple endpoints for basic and enhanced telephony services
An extension of the Simple Gateway Control Protocol (SGCP) protocol and supports SGCP functionality in addition to several enhancements
Allows remote control of various devices
Stimulus protocol
Endpoints and gateways cannot function alone
Uses IETF SDP
Addressing by E.164 telephone number
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-3
Why MGCP
Advantages of MGCP gateways: Alternative dial tone for VoIP environments
Simplified configuration for VoIP dial peers
Simplified migration
Centralized dial plan configuration on the Cisco Unified Communications Manager
Centralized gateway configuration on the Cisco Unified Communications Manager
Simplified Cisco IOS configuration
Supports QSIG supplementary services with Cisco Unified Communications Manager
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-4
MGCP Components
Call Agent (MGCP)
IPPRIPRI
PSTN
Residential Gateway Connecting POTS phones
to an IP network
Trunking Gateway Connecting PSTN-bearer
channels to an IP network
FXS*
Cisco Unified Communications
Manager
Cisco Voice Gateways
FXS = Foreign Exchange Station
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-5
MGCP Gateways
Call processing is done by a call agent such as Cisco Unified Communications Manager.
Calls are routed via route patterns on the Cisco Unified Communications Manager, not by dial peers on the gateway.
Supported Gateways
– Residential gateway
– Trunking gateway
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-6
MGCP Gateways (Cont.)
MGCP uses endpoints and connections to construct a call.
– Endpoints:
Sources of or destinations for data
Physical or logical locations in a device
– Connections:
Point-to-point
Multipoint
MGCP uses UDP for establishing audio connections over IP networks.
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-7
Call Agents
Call Agent
GatewayGateway
IP
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-8
Basic MGCP Concepts
Calls and connections
Events and signals
Package types
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-9
Create Connection (CRCX)
Create Connection (CRCX)
Modify Connection (MDCX)
User Information Exchange
Delete Connection (DLCX)
Delete ACKDelete Connection (DLCX)
Delete ACK
Calls and Connections
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-10
Control Commands
AuditEndpoint (AUEP)
AuditConnection (AUCX)
CreateConnection (CRCX)
ModifyConnection (MDCX)
DeleteConnection (DLCX)
NotificationRequest (RQNT)
Notify (NTFY)
RestartInProgress (RSIP)
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-11
Package Types
Enable with the mgcp package-capability command:
– Trunk
– Line
– Dual-tone multifrequency (DTMF)
– Generic media
– Real-Time Transport Protocol (RTP)
– Announcement server
– Script
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-12
Call FlowsCall
Agent
Gateway A Gateway B
Ringing,Then Answer
Off Hook andDialed 5551234
On Hook
RQNT RQNT
RQNT ResponseRQNT Response
NTFY
CRCX
CRCX Response
(SDP)MDCX (Encapsulated
RQNT, SDP)
MDCX Response
DLCX
DLCX Response
NTFY
DLCX
CRCX (SDP,Encapsulated
RQNT)
CRCX
Response (SDP)
DLCX Response
RTP StreamRTP Stream
RTCP Stream
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-13
Configuring MGCP Gateways
Residential gateway
– Dial peer configuration
Trunking gateway
– Controller configuration
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-14
Configuring an MGCP Residential Gateway
Residential Gateway
Cisco Unified Call
Manager172.20.5.20
IP
router(config)# ccm-manager mgcprouter(config)# mgcprouter(config-mgcp)# mgcp call-agent 172.20.5.20 service-type mgcprouter(config)# dial-peer voice 1 potsrouter(config-dialpeer)# service mgcpapprouter(config-dialpeer)# port 1/0/0router(config)# dial-peer voice 2 potsrouter(config-dialpeer)# service mgcpapprouter(config-dialpeer)# port 1/0/1router(config-dialpeer)# exitrouter(config)# mgcp package-capability dtmf-packagerouter(config)# mgcp package-capability gm-packagerouter(config)# mgcp package-capability line-packagerouter(config)# mgcp package-capability rtp-packagerouter(config)# mgcp default-package line-package
1/0/0
1/0/1
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-15
Configuring an MGCP Trunk Gateway
router(config)# ccm-manager mgcprouter(config)# mgcp 4000router(config)# mgcp call-agent 10.1.1.201 4000router(config)# controller t1 0/1/0router(config-controller)# framing esfrouter(config-controller)# clock source internalrouter(config-controller)# ds0-group 1 timeslots 1-24 type none service mgcprouter(config)# controller t1 0/1/1router(config-controller)# framing esfrouter(config-controller)# clock source internalrouter(config-controller)# ds0-group 1 timeslots 1-24 type none service mgcp
MGCP Gateway
Cisco Unified Call Manager 10.1.1.201
PSTNIP Phones
WAN
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-16
IP Network
G3 Fax G3 Fax
T.38 Gateway
T.38 Gateway
Router(config)# ccm-manager mgcpRouter(config)# no ccm-manager fax protocol ciscoRouter(config)# mgcpRouter(config)# mgcp call-agent 10.1.1.10 service-type mgcp version 0.1Router(config)# mgcp package-capability fxr-packageRouter(config)# mgcp package-capability rtp-packageRouter(config)# mgcp fax rate 14400Router(config)# mgcp timer 300Router(config)# mgcp fax-relay sg3-to-g3
Cisco Unified Call Manager Cisco
Unified Call Manager
San Jose Austin
10.1.1.10
Configuring Fax Pass-Through and Relay with MGCP Gateways
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-17
router# show mgcp MGCP Admin State ACTIVE, Oper State ACTIVE - Cause Code NONEMGCP call-agent: 10.1.1.101 4000 Initial protocol service is MGCP 0.1MGCP validate call-agent source-ipaddr DISABLEDMGCP validate domain name DISABLEDMGCP block-newcalls DISABLEDMGCP send SGCP RSIP: forced/restart/graceful/disconnected DISABLED MGCP quarantine mode discard/stepMGCP quarantine of persistent events is ENABLEDMGCP dtmf-relay for VoIP is SDP controlledMGCP dtmf-relay for voAAL2 is SDP controlledMGCP voip modem passthrough disabledMGCP voaal2 modem passthrough disabledMGCP voip tremolo modem relay: DisabledMGCP T.38 Named Signalling Event (NSE) response timer: 200MGCP Network (IP/AAL2) Continuity Test timer: 200MGCP 'RTP stream loss' timer: 5MGCP request timeout 500MGCP maximum exponential request timeout 4000MGCP gateway port: 4000, MGCP maximum waiting delay 3000
Verifying MGCP
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-18
MGCP restart delay 0, MGCP vad DISABLEDMGCP rtrcac DISABLEDMGCP system resource check DISABLEDMGCP xpc-codec: DISABLED, MGCP persistent hookflash: DISABLEDMGCP persistent offhook: ENABLED, MGCP persistent onhook: DISABLEDMGCP piggyback msg ENABLED, MGCP endpoint offset DISABLEDMGCP simple-sdp DISABLEDMGCP undotted-notation DISABLEDMGCP codec type g711ulaw, MGCP packetization period 20MGCP JB threshold lwm 30, MGCP JB threshold hwm 150MGCP LAT threshold lwm 150, MGCP LAT threshold hwm 300MGCP PL threshold lwm 1000, MGCP PL threshold hwm 10000MGCP CL threshold lwm 1000, MGCP CL threshold hwm 10000MGCP playout mode is adaptive 60, 40, 200 in msecMGCP Fax Playout Buffer is 300 in msecMGCP media (RTP) dscp: ef, MGCP signaling dscp: af31MGCP default package: trunk-packageMGCP supported packages: gm-package dtmf-package trunk-package line-package hs-package atm-package ms-package dt-package mo-package
res-package mt-package fxr-package md-package MGCP Digit Map matching order: shortest matchSGCP Digit Map matching order: always left-to-rightMGCP VoAAL2 ignore-lco-codec DISABLED
Verifying MGCP (Cont.)
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-19
Verifying MGCP (Cont.)
MGCP T.38 Max Fax Rate is DEFAULTMGCP T.38 Fax is ENABLEDMGCP T.38 Fax ECM is ENABLEDMGCP T.38 Fax NSF Override is DISABLEDMGCP T.38 Fax Low Speed Redundancy: 0MGCP T.38 Fax High Speed Redundancy: 0MGCP Fax relay SG3-to-G3: ENABLEDMGCP control bind :DISABLEDMGCP media bind :DISABLEDMGCP Upspeed payload type for G711ulaw: 0, G711alaw: 8MGCP Dynamic payload type for G.726-16K codecMGCP Dynamic payload type for G.726-24K codecMGCP Dynamic payload type for G.Clear codecMGCP Dynamic payload type for NSE is 100MGCP Dynamic payload type for NTE is 99MGCP rsip-range is enabled for TGCP only.MGCP Guaranteed scheduler time is disabledMGCP DNS stale threshold is 30 seconds
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-20
router# show ccm-managerMGCP Domain Name: cisco-voice-01Priority Status Host============================================================Primary Registered 10.89.129.211First Backup NoneSecond Backup None
Current active Call Manager: 10.89.129.211Backhaul/Redundant link port: 2428Failover Interval: 30 secondsKeepalive Interval: 15 secondsLast keepalive sent: 5w1d (elapsed time: 00:00:04)Last MGCP traffic time: 5w1d (elapsed time: 00:00:04)Last failover time: NoneSwitchback mode: GracefulMGCP Fallback mode: Not SelectedLast MGCP Fallback start time: 00:00:00Last MGCP Fallback end time: 00:00:00
Configuration Error History:
Verifying MGCP (Cont.)
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-21
Verifying MGCP (Cont.)
router# show mgcp endpoint
Interface T1 0/1/0
ENDPOINT-NAME V-PORT SIG-TYPE ADMIN S0/SU1/ds1-0/1@HQ-1 0/1/0:1 none up S0/SU1/ds1-0/2@HQ-1 0/1/0:1 none up S0/SU1/ds1-0/3@HQ-1 0/1/0:1 none up S0/SU1/ds1-0/4@HQ-1 0/1/0:1 none up S0/SU1/ds1-0/5@HQ-1 0/1/0:1 none up S0/SU1/ds1-0/6@HQ-1 0/1/0:1 none up S0/SU1/ds1-0/7@HQ-1 0/1/0:1 none up S0/SU1/ds1-0/8@HQ-1 0/1/0:1 none up S0/SU1/ds1-0/9@HQ-1 0/1/0:1 none up S0/SU1/ds1-0/10@HQ-1 0/1/0:1 none up
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-22
Verifying MGCP (Cont.)
router# show mgcp statistics
UDP pkts rx 8, tx 9Unrecognized rx pkts 0, MGCP message parsing errors 0Duplicate MGCP ack tx 0, Invalid versions count 0CreateConn rx 4, successful 0, failed 0DeleteConn rx 2, successful 2, failed 0ModifyConn rx 4, successful 4, failed 0DeleteConn tx 0, successful 0, failed 0NotifyRequest rx 0, successful 4, failed 0AuditConnection rx 0, successful 0, failed 0AuditEndpoint rx 0, successful 0, failed 0RestartInProgress tx 1, successful 1, failed 0Notify tx 0, successful 0, failed 0ACK tx 8, NACK tx 0ACK rx 0, NACK rx 0IP address based Call Agents statistics:IP address 10.24.167.3, Total msg rx 8, successful 8, failed 0
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-23
Summary
MGCP defines an environment for controlling telephony gateways from a centralized call agent.
There are several advantages to using MGCP controlled gateways as voice gateways.
MGCP components include endpoints, gateways, and call agents.
Calls and connections are basic concepts in MGCP.
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-24
Summary (Cont.)
MGCP call flow consists of an exchange of messages between the call agent and the gateway.
The mgcp command can be used to configure residential and trunk gateways on a Cisco router.
Several show and debug commands help to verify an MGCP configuration.
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-25
Voice Gateway
Voice-Enabled Router
IP Telephony Router with Cisco Unified Communications Manager Express
Cisco Unified Communications Manager
Switch
Router
POTS Phone
IP Phone
Network Cloud
Line: Serial Line: Ethernet
PC
PBX
Cisco Unified Border Element
IP
Icons
© 2008 Cisco Systems, Inc. All rights reserved. CVOICE v6.0—3-26