IPv4 and IPv6 Overview of Network Configuration

Managing Network Resources 4-3 associated with that Network Interface Card’s NIC address is examined to determine the external listen address to embed in SIP headers. If your system uses a multi-homed load balancer having two public addresses, you must also define a pair of channels to configure both public addresses. If the engine tier server has only one NIC, you must define a second, logical address on the NIC to configure a dedicated channel for the second public address. In addition, you must configure your IP routing policies to define which logical address is associated with each public load balancer address.

4.3 Enabling Domain Name Service DNS Support

Oracle WebLogic Communication Services supports multi-home for resolving the transport, IP address and port number of a proxy required to send a SIP message. This matches the behavior described in RFC 3263 http:www.ietf.orgrfcrfc3263.txt . multi-home may also used when routing responses in order to resolve the IP address and port number of a destination. To configure multi-home support: 1. Log in to the Administration Console for the Oracle WebLogic Communication Services domain you want to configure. 2. Select the SipServer node in the left pane of the Console.

3. Select the Configuration General tab in the right pane.

4. Select Enable multi-home Server Lookup.

5. Click Save to save your changes.

When you enable multi-home lookup, the server can use multi-home to: ■ Discover a proxy servers transport, IP address, and port number when a request is sent to a SIP URI. ■ Resolve an IP address andor port number during response routing, depending on the contents of the Sent-by field. For proxy discovery, Oracle WebLogic Communication Services uses multi-home resolution only once per SIP transaction to determine transport, IP, and port number information. All retransmissions, ACKs, or CANCEL requests are delivered to the same address and port using the same transport. For details about how multi-home resolution takes place, see RFC 3263 http:www.ietf.orgrfcrfc3263.txt . When a proxy is required to send a response message, Oracle WebLogic Communication Services uses multi-home lookup to determine the IP address andor port number of the destination, depending on the information provided in the Sent-by field and through header. Note: Because multi-home resolution is performed within the context of SIP message processing, any multi-home performance problems result in increased latency. Oracle recommends using a caching multi-home server in a production environment to minimize potential performance problems.