To use the H.323 Support for Virtual Interfaces feature, first ensure that the VoIP gateway functionality is enabled. For more information about enabling the VoIP gateway functionality, see Configuring H.323 VoIP Gateway for Cisco Access Platforms. To configure a source IP address for the gateway, do the following: Command Purpose
Step 1
Router# config term
Enters global configuration mode.
Step 2
Router(config)# interface type slot/port
Enters interface configuration mode to configure parameters for the&nb! sp;specified interface.
The type attribute indicates the type of interface. The slot/port attribute indicates the location of the interface in the router.
Step 3
Router(config-if)# h323-gateway voip bind srcaddr ip_address
Sets the source IP address to be used for this gateway.
The ip_address attribute indicates the address to be used as the source IP address for the gateway.
--------------------------------------------------------------------------------
Note You can issue the h323-gateway voip bind srcaddr command on any ! interface in the router. Issuing the com mand for one interface assigns the source address for the entire router.
--------------------------------------------------------------------------------
Verifying the Gateway's Source IP Address
To verify the gateway's source IP address, enter the show run command. The output shows the source IP address that is bound to the interface.
router# show run
Building configuration...
Current configuration:
!
.
.
.
interface Loopback0
ip address 1.1.1.1 255.255.255.0
no ip directed-broadcast
h323-gateway voip bind srcaddr 1.1.1.1
!
interface Ethernet0/0
ip address 172.1! 8.194.50 255.255.255.0
no ip directed-broadcast
h323-gateway voip interface
h323-gateway voip id j70f_2600_gk2 ipaddr 172.18.194.53 1719
h323-gateway voip h323-id j70f_3640_gw1
h323-gateway voip tech-prefix 3#
.
.
.
Configuration Examples
In the following example, the Ethernet 0/0 interface is used as the gateway interface. For convenience, we have also specified the h323-gateway voip bind srcaddr command on the same interface. The designated source IP address is the same as the IP address assigned to the interface.
interface Ethernet0/0
ip address 172.18.19! 4.50 255.255.255.0
no ip directed-broadcast
h323-gateway voip interface
h323-gateway voip id j70f_2600_gk2 ipaddr 172.18.194.53 1719
h323-gateway voip h323-id j70f_3640_gw1
h323-gateway voip tech-prefix 3#
h323-gateway voip bind srcaddr 172.18.194.50
Command Reference
This section documents new or modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.1 command reference publications.
h323-gateway voip srcaddr
To designate a source IP address for the voice gateway, use the h323-gateway voip bind srcaddr command. To remove the source IP address, use the ! no form of the command.
h323-gateway voip bind srcaddr ip_address
no h323-gateway voip bind srcaddr
Syntax Description ip_address
Specify the source IP address in dotted-decimal notation.
Defaults
There are no default behaviors or values for this command.
Command Modes
Interface configuration
Command History Release Modification
12.1(2)T
This command was introduced.
Usage Guidelines
You can issue this command on any interface in the router. You do not have to issue it&nb! sp;on the interface that you defined as& nbsp;the voice gateway interface (although it may be more convenient to do so). Issuing the command for one interface assigns the source IP address for the entire router.
Examples
The following example assigns a source IP address of 1.1.1.1:
h323-gateway voip bind srcaddr 1.1.1.1
Related Commands
None
Glossary
gatekeeper―A gatekeeper maintains a registry of devices in the multimedia network. The devices register with the gatekeeper at startup, and request admission to a call from the gatekeeper.
The gatekeeper is an H.323 entity&nbs! p;on the LAN that provides address translation and control access to the LAN for H.323 terminals and gateways. The gatekeeper may provide other services to the H.323 terminals and gateways, such as bandwidth management and locating gateways.
gateway―A gateway allows H.323 terminals to communicate with non-H.323 terminals by converting protocols. A gateway is the point at which a circuit-switched call is encoded and repackaged into IP packets.
A H.323 gateway is an endpoint on the LAN that provides real-time, two-way communications between H.323 terminals&nbs! p;on the LAN and other ITU-T terminals&n bsp;in the WAN, or to another H.323 gateway.
H.323―An International Telecommunication Union (ITU-T) standard that describes packet-based video, audio, and data conferencing. H.323 is an umbrella standard that describes the architecture of the conferencing system, and refers to a set of other standards (H.245, H.225.0, and Q.931) to describe its actual protocol.
RAS―Registration, admission, and status protocol. This is the protocol that is used between endpoints and the gatekeeper to perform management functions. The RAS signaling function performs registration, admissions, ! ;bandwidth changes, status, and disengage procedures between the VoIP gateway and the gatekeeper.
RTP―Real-time transport protocol. One of the IPv6 protocols. RTP is designed to provide end-to-end network transport functions for applications transmitting real-time data, such as audio, video, or simulation data, over multicast or unicast network services. RTP provides services such as payload type identification, sequence numbering, timestamping, and delivery monitoring to real-time applications.
VoIP―Voice over IP. The ability to carry normal telephone-style voice over an IP-based ! Internet with POTS-like functionality, reliability , and voice quality. VoIP is a blanket term which generally refers to Cisco's standards-based (H.323, etc.) approach to IP voice traffic.
