Configuring NAT Pools for the Packet Gateway

You can configure a network address translation (NAT) pool that is exclusive to the packet gateway feature. This topic shows how to create the following types of NAT pools for PGCP:

• Configuring a Remotely Controlled NAT Pool
• Configuring a NAT Pool Selected Based on Transport Protocol

Configuring a Remotely Controlled NAT Pool

Step-by-Step Procedure

To configure a remotely-controlled NAT pool:

1. Create a NAT pool, and specify a name for the pool.
   [edit services]
   user@host#edit nat pool pgcp-pool
2. Configure an address range for the pool.
   [edit services nat pool pgcp-pool]
   user@host#set address-range low 10.10.20.100 high 10.10.30.100
3. Configure a range of ports. If you configure the NAT pool as remotely controlled, you must set a specific port range rather than using an automatic assignment of ports.
   [edit services nat pool pgcp-pool]
   user@host#set port range low 10000 high 50000
4. (Optional) Specify that the NAT pool is used exclusively by the packet gateway.
   [edit services nat pool pgcp-pool]
   user@host#set pgcp
5. (Optional) Specify that the PGC controls the addresses and ports in a NAT pool. The PGC reserves the addresses and ports when it requests specific local NAT bindings for remote addresses. (By default, the PG controls the addresses and ports in a pool.)
   [edit services nat pool pgcp-pool]
   user@host#set pgcp remotely-controlled
6. (Optional) Configure the number of ports allocated to voice and video flows on the MultiServices PIC. This value is useful when one port is allocated for Real-Time Transport Protocol (RTP), and the accompanying Real-Time Control Protocol (RTCP) flow uses the other port. By default, 2 ports are available. To support the extra ports required for combined voice and video flows, you can specify 4 ports.
   [edit services nat pool pgcp-pool]
   user@host#set pgcp ports-per-session 4

Configuring a NAT Pool Selected Based on Transport Protocol

Step-by-Step Procedure

To configure a NAT pool that can be selected based on its transport protocol:

1. Create a NAT pool, and specify a name for the pool.
   [edit services]
   user@host#edit nat pool pgcp-pool
2. Configure an address range for the pool.
   [edit services nat pool pgcp-pool]
   user@host#set address-range low 10.10.20.100 high 10.10.30.100
3. Configure a range of ports. If you configure the NAT pool as remotely controlled, you must set a specific port range rather than using an automatic assignment of ports.
   [edit services nat pool pgcp-pool]
   user@host#set port range low 10000 high 50000
4. (Optional) Specify that the NAT pool is used exclusively by the packet gateway.
   [edit services nat pool pgcp-pool]
   user@host#set pgcp
5. Specify one or more transport protocols that must match the transport protocol in the media descriptor of Add or Modify requests from the PGC.
   [edit services nat pool pgcp-pool]
   user@host#set pgcp transport [rtp-avp udp]
6. Specify that the port is automatically assigned.
   [edit services nat pool pgcp-pool]
   user@host#set port automatic
7. (Optional) Configure the number of ports allocated to voice and video flows on the MultiServices PIC. This value is useful when one port is allocated for Real-Time Transport Protocol (RTP), and the accompanying Real-Time Control Protocol (RTCP) flow uses the other port. By default, 2 ports are available. To support the extra ports required for combined voice and video flows, you can specify 4 ports.
   [edit services nat pool pgcp-pool]
   user@host#set pgcp ports-per-session 4

Related Topics

• Chapter 9, Summary of Network Address Translation Configuration Statements in JUNOS Services Interfaces Configuration Guide.
• Twice NAT for VoIP Traffic Overview.