R3721-F3210-F3171-HP High-End Firewalls NAT and ALG Configuration Guide-6PW101

The H.323 ALG configuration is similar to the SIP ALG configuration. This example describes the SIP ALG

configuration.

Network requirements

As shown in Figure 54, a company uses the private network segment 192.168.1.0/24, and has four

public network addresses: 5.5.5.1, 5.5.5.9, 5.5.5.10, and 5.5.5.11. SIP UA 1 is on the internal network

and SIP UA 2 is on the external network.

Configure NAT and ALG on the Firewall so that SIP UA 1 and SIP UA 2 can communicate by using their

aliases, and SIP UA 1 selects an IP address from the range 5.5.5.9 to 5.5.5.11 when registering with the

SIP server on the external network.

Figure 54 Network diagram

Configuration procedure

# Configure the address pool and ACL.

<Firewall> system-view

[Firewall] nat address-group 1 5.5.5.9 5.5.5.11

[Firewall] acl number 2001

[Firewall-acl-basic-2001] rule permit source 192.168.1.0 0.0.0.255

[Firewall-acl-basic-2001] rule deny

[Firewall-acl-basic-2001] quit

# Enable ALG for SIP.

[Firewall] alg sip

# Configure NAT.

[Firewall] interface GigabitEthernet 0/2

[Firewall-GigabitEthernet0/2] nat outbound 2001 address-group 1

NBT ALG configuration example

Network requirements

As shown in Figure 55, a company using the private network segment 192.168.1.0/24 wants to provide

NBT services to the outside.

Configure NAT and ALG on the Firewall so that Host A uses 5.5.5.9 as its external IP address, the WINS

server uses 5.5.5.10 as its external IP address, and Host B can access the WINS server and Host A by

using host names.