Unanswered Question

This is more of a "How does this work" question.

This is an output from a "show call active voice brief" There is only 1 call active on this gw

Telephony call-legs: 0

SIP call-legs: 1

H323 call-legs: 1

Call agent controlled call-legs: 0

SCCP call-legs: 2

Multicast call-legs: 0

Total call-legs: 4

This gateway is SIP coming from the PSTN, then we convert it to H323 to the CCM (trunk). My question is, where does skinny come into this. How does the gw talk to the CM (skinny)? H323?

My guess is that CM talks to phones and gateways with Skinny, H323 is only used when a call is being setup?

Or does the Gateway talk H323 to the CM, CM acting as a H323 proxy converts the singal into skinny??


sh run

Building configuration...

Current configuration : 7900 bytes

version 12.4

service timestamps debug datetime msec localtime

service timestamps log datetime msec localtime

no service password-encryption

service sequence-numbers

hostname Test


boot system flash c2800nm-ipvoicek9-mz.124-11.T.bin


logging buffered 100000000

no logging console

no aaa new-model

clock timezone MST -7

clock summer-time MST recurring 2 Sun Mar 2:00 1 Sun Nov 2:00


ip cef

no ip domain lookup

multilink bundle-name authenticated

voice-card 0


voice service voip

allow-connections h323 to sip

allow-connections sip to h323

voice class h323 1

h225 timeout tcp establish 3

call start fast

call preserve

translation-rule 1

Rule 1 ^4 6

interface GigabitEthernet0/0

ip address 2XX.2XX.1XX.1XX

ip access-group WANdefault in

duplex full

speed 10

no cdp enable

interface GigabitEthernet0/1

ip address

duplex full

speed 100

sccp local GigabitEthernet0/1

sccp ccm identifier 1 version 4.1


sccp ccm group 1

bind interface GigabitEthernet0/0

associate ccm 1 priority 1

associate profile 1 register MTP41123456789

dspfarm profile 1 mtp

description MTP for CCM 4.1.3

codec g711ulaw

maximum sessions software 100

associate application SCCP

dial-peer voice 100 voip

destination-pattern .T

session protocol sipv2

session target ipv4:XX.XX.XX.XX:4060

dtmf-relay rtp-nte digit-drop

codec g711ulaw

ip qos dscp cs5 media

ip qos dscp cs5 signaling

no vad

dial-peer voice 200 voip

preference 2

destination-pattern 321[0-9]

voice-class h323 1

session target ipv4:

codec g711ulaw

no vad

I have this problem too.
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ivillegas Mon, 06/02/2008 - 10:41

Skinny enables voice communication between two Skinny clients through the use of a CM. Typically, the CM provides service to the Skinny clients on TCP Port 2000. Initially, a Skinny client connects to the CM by establishing a TCP connection; the client will also establish a TCP connection with a secondary CM, if available. After the TCP connection is established, the client will register with the primary CM, which will be used as the controlling CM until it reboots or there is a keepalive failure. Thus, the Skinny TCP connection between the client and the CM exists forever and is used to establish calls coming to or from the client. If a TCP connection failure is detected, the secondary CM is used. All data channels established with the previous CM remain active and will be closed after the end parties hang up the call.

Jaime Valencia Mon, 06/02/2008 - 19:18

the only thing i could think that could be having those SCCP call legs would be the MTP control for each side of the call.

if you try 2 calls at the same time do you get 4 sccp call legs?



if this helps, please rate


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