Diameter Configuration Overview
This section describes steps that are specific to configuring Diameter Remote Network Elements.
The basic steps for configuring a Diameter Remote Network Element are:
- Creating and naming the Diameter Remote Network Element. See Creating and Naming the Remote Network Element.
- Configuring the Diameter connections
- Assigning the function(s) and configuring the Implicit routing rules (if applicable to the function).
Configuring Diameter Connections
Configuring Diameter connections is straightforward. Each connection is configured separately with the following parameters of the remote peer:
- Origin-Host
- IP Address and format (either IPv4 or IPv6)
- The port number the remote peer uses for Diameter messages.
- The transport protocol for Diameter messages (either SCTP or TCP)
Detecting Diameter Connection Failures
To detect a connection failure, the Diameter protocol uses Application-level heartbeat messages called Device-Watchdog-Request and Device-Watchdog-Answer messages. These messages are periodically sent when a connection is idle and when a timely response has not been received for an outstanding request.
In the IMS AAA Server, Diameter connections can also be configured to actively attempt to connect to the Remote Network Element. If this feature is enabled and a connection fails, the server will periodically attempt to re-establish the connection.
Assigning Functions to a Diameter Remote Network Element
To assign the functions to a Diameter Remote Network Element, select the function from the predefined list in the IMS AAA Server Administrator. Most functions require no further configuration; the IMS AAA Server internally configures the associated 3GPP reference point parameters. However, some functions require you to configure Implicit routing rules.
Also see Functions37.
Configuring Implicit Routing Rules for Diameter Functions
Certain network element functions require routing rules to be configured when you assign the function. These routing rules are called Implicit routing rules. For instance, when you assign the HSS function to a Diameter Remote Network Element, you need to specify which subscribers are served by the HSS. You do this by assigning the HSS function and configuring the implicit routing in the function configuration.
Implicit routing is usually based on subscriber identity or realm; the exception to this is the WAG function. See Configuring Implicit Routing Rules for more information. In 3GPP WLAN networks, the subscriber identity is the IMSI (International Mobile Subscriber Identity) of the mobile device (WLAN UE).
The following Diameter functions require you to configure implicit routing rules:
For more information on implicit routing rules, see Request Routing and Request Routing Rules.
Example Diameter Configuration
Figure 12 shows a simple Diameter configuration. This illustration shows example configuration parameters for the Remote Network Element, as well as for the IMS AAA Server.
In this example, the Remote Network Element has two connections: "Connection 1" with IP Address 171.20.33.4, and "Connection 2" with IP Address 171.20.33.5. Either Round Robin or Primary/Backup could be used to manage the two connections.
