Suppress SIP Reliable Response Support for IWF

For IWF-originated calls, the Oracle® Enterprise Session Border Controller now allows you to configure the suppression of the SIP 100rel option tag on a per-H.323 interface (stack) basis.

When a calls originates on the H.323 side for a call that requires interworking between H.323 and SIP, the Oracle® Enterprise Session Border Controller inserts the 100rel option tag in the Supported header of the outgoing SIP INVITE. Although this behavior is required for RFC 3262 conformance, and is ignored by endpoints that do not support this RFC, suppressing the reliable response can alleviate processing burdens and avoid the possibility that an endpoint could mishandle the response.

In addition, enabling this feature suppresses the same 100rel options tag in the Required header for outgoing IWF responses for which an incoming SIP INVITE had that same tag in its Supported header. If an incoming INVITE requires reliable provisional responses and the SIP feature configuration is set to accept the 100rel, the Oracle® Enterprise Session Border Controller then includes the 100rel option tag in the outgoing response’s Required header. When the SIP feature is not so configured, the Oracle® Enterprise Session Border Controller rejects the INVITE with a 420 Bad Extension response.

Without this option, you can suppress the reliable response on a global basis or per SIP next-hop by using the SIP feature configuration. However, using this feature allows a finer degree of granularity by making the functionality only applicable to IWF calls that originate in H.323.

suppress100rel Configuration

To suppress the SIP 100rel option tag:

In Superuser mode, type configure terminal and press Enter.
```
ORACLE# configure terminal
```
Type session-router and press Enter.
```
ORACLE(configure)# session-router
```

Type h323 and press Enter.

ORACLE(session-router)# h323
ORACLE(h323)#

Type h323-stacks and press Enter.
```
ORACLE(h323)# h323-stacks
ORACLE(h323-stack)#
```
If you are adding support for this feature to a pre-existing H.323 interface (stack), then you must select (using the ACLI select command) the configuration that you want to edit.
options—Set the options parameter by typing options, a Space, the option name suppress100rel with a plus sign in front of it, and then press Enter.
```
ORACLE(h323-stack)# options +suppress100rel
```
If you type options and then the option value for either of these entries without the plus sign, you will overwrite any previously configured options. In order to append the new option to this configuration’s options list, you must prepend the new option with a plus sign as shown in the previous example.