SIP-H323 CUBE example help, please.......

[mmertens]

I've got the following example from Cisco

and need some assistance with some IP address references in the doc. Our CM is 4.1(3) and we'll be running H323 to the CUBE VGW and SIP out to the carrier.

I assume the registrar address is the carrier peer.....correct? I'm curious if there is a "best practice" for which address on my CUBE router to give them to peer to (obviously they'll need to be able to route to it). But is there a preference that I have the carrier peer to my serial, ethernet or loopback interface? Any thoughts?

Thanks!

http://www.cisco.com/en/US/products/sw/voicesw/ps5640/products_configuration_example09186a00808ead0f.shtml

!

voice service voip

allow-connections h323 to sip

allow-connections sip to h323

allow-connections sip to sip

allow-connections h323 to h323

!

dial-peer voice 1 voip

session target ipv4:10.13.8.150

incoming called-number 8...

dtmf-relay h245-alphanumeric

codec g711ulaw

!

dial-peer voice 2 voip

destination-pattern 8...

session protocol sipv2

session target ipv4:10.13.8.16

dtmf-relay rtp-nte

codec g711ulaw

!

sip-ua

registrar ipv4:10.1.1.10

or

registrar dns:csps.cisco.com

authentication username xyz password xyz realm cisco.com

[Nicholas Matthews · Accepted solution]

The one thing you'll want to keep in mind is that if you end up binding your media/signaling to an address, both CUCM and your provider must have reachability to that address.

Generally for CUBE, it's easier to leave it unbound. If there is a chance for asymmetric routing, then bind. When you bind a SIP address, the gateway will not listen on any other port so having reachibility from both sides is critical.

I would give the SIP provider an address both your CUCM and the provider can reach. If one doesn't exist, you don't have much choice but to give your public. If you only have one internet connection, having a loopback will not serve much purpose. If you have redundant connections to the internet, use your loopback.

hth,

nick

[mmertens]

Thanks Nick!

[mmertens]

This document also mentions the need for MTP when doing H323-SIP:

Do I need to create an MTP in CM under Service/Media Resource; or as the document shows, when I check "MTP required" under my CM H323 config, that creates the MTP?

In the IOS MTP config, when I specify MTP type as "software" does that infer the MTP will reside in CM, rather than the VGW? (Such as the reference of hardware CFB vs. software CFB)?

MTP Co-resident with the Cisco Unified Border Element

If a software MTP is required by the Cisco Unified Communications Manager configuration, this can be configured on the same router used for the Cisco Unified Border Element.

This is the configuration on the Cisco Unified Border Element for an MTP:

sccp local FastEthernet0/1

sccp ccm 15.5.34.1 identifier 1 version 4.1

sccp

!

sccp ccm group 1

associate ccm 1 priority 1

associate profile 1 register MTP

!

dspfarm profile 1 mtp

codec g711ulaw

maximum sessions software 100

associate application SCCP

Thanks!

Mike.

[Nicholas Matthews]

Hi Mike,

There are a lot of call flows that require MTP for H323-SIP. It's generally suggested, but not required (at least for basic calls).

You must have a MTP in the MRGL of the gateway or in the default list (a MTP that is not in any MRG).

When you define 'software' you are telling the router to use CPU cycles rather than DSP hardware to do the processing. The only CCM MTPs are the defaults that are automatically installed.

hth,

nick

[Derrick Filippelli]

Just wondering about binding to the IP address of the interface. If the interface IP that you are bound to is NATed  will that affect the SIP providers ability to reach the gateway?

interface FastEthernet0/0

ip address 192.168.2.3 255.255.255.0

duplex auto

speed auto

h323-gateway voip interface

h323-gateway voip h323-id 192.168.2.3

h323-gateway voip bind srcaddr 192.168.2.3

Nicholas Matthews wrote:
The one thing you'll want to keep in mind is that if you end up binding your media/signaling to an address, both CUCM and your provider must have reachability to that address.
Generally for CUBE, it's easier to leave it unbound.  If there is a chance for asymmetric routing, then bind.  When you bind a SIP address, the gateway will not listen on any other port so having reachibility from both sides is critical.
I would give the SIP provider an address both your CUCM and the provider can reach.  If one doesn't exist, you don't have much choice but to give your public.  If you only have one internet connection, having a loopback will not serve much purpose.  If you have redundant connections to the internet, use your loopback.
hth,
nick