PCE Network Deployments

PCE supports the following options, depending on the network configuration requirements:

• Basic PCE
  
  
• Enhanced PCE
         
• Modifying PCE NA Default Configuration

Both the Basic and Enhanced PCE support STP mated pair configuration.

Adding PCE to a Deployed System

Contact Customer Support if you add a PCE license (Basic or Enhanced) to an already deployed system or if a PCE license must be changed between Basic and Enhanced PCE on such a system.

Basic PCE

The purpose of the Basic PCE is to separate private and public addressing spaces by presenting one or more PCs to the public network while concurrently managing a full private network.

The Basic PCE has one NA in the public network and one NA in the private network.

Enhanced PCE

The Enhanced PCE option can provide you with the same functionality as the Basic PCE, but its main purpose is to support the same PC in two private networks. This ability allows you to replace an existing softswitch with a new softswitch without any service outage. Hence, the PCE presents one PC to the public network while directing traffic to the new and existing softswitches as determined by the trunk mappings.

The Enhance PCE has one NA in the public network and two NAs in the private network.

The following restrictions apply to the Enhanced PCE functionality:

• only two private networks are allowed with the same PC during the traffic migration from the existing switch to the new one. If the private deployment has no duplicate PC, the private network can be fully contained in a single private network configuration using the Basic PCE option.
  
  
• multiple private NAs are only allowed for migrating traffic from an existing switch to a new switch. Because the MTP3 manages local network traffic without involving the PCE, transferring a message signaling unit (MSU) from the first private network to the second private network requires virtual assignments for switches with the identical PC. The virtual assignment impacts all the local private network switches routing configuration.

Modifying PCE NA Default Configuration

The PCE Network Appearances (NAs) are created by default if your system is licensed for PCE. Also, the PCE NAs are numbered by default as NA 1 (public) NA 2 and NA 3 (private). Although it is not recommended, you can change this numbering scheme for newly installed systems directly after you completed the initial configuration process (for more information about this process, refer to the appropriate sections in the Installation Guides).

You can also change this numbering scheme on an existing system when you purchase a new PCE license. In this case, PCE automatically appears in the Main Menu with the PCE NAs created as described in the preceding paragraph. The PCE NA numbering can be reconfigured as required from 1 to 99 with the following limitations:

• PCE traffic must be deactivated (refer to To activate or deactivate PCE traffic)
  
  
• corresponding NAs must be added at MTP3 (and SCCP/GTT NAs, if required) before activating the traffic again (refer to the appropriate section in the SS7 Application Guide 1).
  
  
• If GTT routing is required on any of the PCE NAs, set the GTT NA Connection Type to PCE for associated GTT NA creations (refer to Global Title Translation).

PCE Node Architecture

PCE is a distributed process that resides across a mated pair of STPs (see the following figure).

Basic PCE Node Architecture