Goal (short description)
Setup SIP-H.323 translator and/or SIP/H.323 SBC (involved in sip to sip and h.323 to h.323 calls)
Applicability
Protocol translator and/or border gateway for SIP and H.323
Prerequisites (OS, dependencies on other software)
- Appropriate Cisco router with appropriate IOS. See datasheet for router type, memory and IOS requirements.
- Basic IOS configuration knowledge
- Router with configured network access
Configuration (OS agnostic)
Product page
Configuration guides
Call direction and translation section
voice service voip allow-connections h323 to h323 allow-connections h323 to sip allow-connections sip to h323 allow-connections sip to sip
Allow or ban directions you want to use.
Main protocol section
h323 call start interwork sip
Here can be set protocol parameters like slow start and fast start for H.323. Call start interwork allows translation between these modes. Protocol setting can be changed for particular dial peer i.e. by means of voice-class h323 commands or by appropriate commands directly in dial peers
voice class h323 500 call start fast
Codec class
voice class codec 200 codec preference 1 g711alaw codec preference 2 g711ulaw codec preference 3 gsmfr codec preference 4 g729r8
You can define sets of codecs with preferences and assign these sets to dial peers. Or you can directly assign codec in dial peer, but only one.
Dial peers
SIP dial peer that uses configured sip-server.
dial-peer voice 211 voip destination-pattern 90........ voice-class codec 200 session protocol sipv2 session target sip-server
SIP dial peer that routes traffic to ip.
dial-peer voice 211 voip destination-pattern 91........ voice-class codec 200 session protocol sipv2 session target ipv4:5.6.7.8
H.323 dial peer that uses RAS (configured gatekeeper).
dial-peer voice 1 voip destination-pattern 10......... voice-class codec 200 session target ras
H.323 dial peer that routes to another gw or endpoint
dial-peer voice 1 voip destination-pattern 11......... voice-class codec 200 voice-class h323 500 session target ipv4:9.8.7.6
Specific h323 class is configured to change some parameters.
SIP UA settings
sip-ua nat symmetric role passive nat symmetric check-media-src sip-server dns:domain.dom
Here is defined sip server (used in dial peers) and various sip parameters.
Gatekeeper settings
interterface Loopback0 description MGMT Loopback ip address 1.2.3.4 255.255.255.255 h323-gateway voip interface h323-gateway voip id GK1 ipaddr 1.1.1.1 1718 priority 100 h323-gateway voip id GK2 ipaddr 1.1.1.2 1718 h323-gateway voip h323-id IP2IPGW h323-gateway voip tech-prefix 1# h323-gateway voip bind srcaddr 1.2.3.4
Gatekeeper settings for ras session target in dial peers with primary and secondary gatekeeper. It is not necessary to configure it on Loopback interface.
There seems to be a BUG that affects H.323 slowstart to SIP calls if sip server is not set by ipv4:1.2.3.4.
OS specific help
N/A - There is only CISCO IOS
Validation, confirmation tests
Route call through IP2IP gw.
If you don't use sip server and gatekeeper, set dial peer destinations (session-target) directly to endpoints and call each other ( i.e. sip:numberofh323endpoint@ipofip2ip)