Content Manipulation and Session Agents

PAI Header and FQDN Manipulation

You can configure the SBC to manipulate the content of egress messages using realm parameters instead of HMR. By setting these parameters, you cause the SBC to perform these manipulations on specific SIP methods that egress the realm.

Realm-based content manipulation that applies to surrogate agent operation includes:

P-Asserted Identity (PAI) content
Fully Qualified Domain Name (FQDN) content

PAI Header Manipulation

You can configure the realm-config element with PAI manipulation behavior that applies to the realm's egress traffic.

You set the P-Asserted-Identity parameter in conjunction with the P-Asserted-Identity-For parameter to insert PAI headers into that realm's egress traffic. You specify the methods that you want to include by configuring the P-Asserted-Identity-For parameter for any or all of the following methods:

INVITE
ACK
BYE
REGISTER

You enable the behavior by configuring the P-Asserted-Identity parameter with the PAI value you want to insert. If you do not set both of these parameters, the SBC does not insert the headers. This manipulation deals with the selected headers for egress INVITE and REGISTER flows, and does not interfere with PRACK INVITE flows.

If the originating message does not include any PAI headers, the SBC inserts the headers per configuration. If PAI headers are already present, inserted by an upstream device, the SBC:

Adds any P-Asserted-Identity parameter headers to the top of the header list.
Replaces any existing sip:PAI headers with the sip:PAI headers you configure with the P-Asserted-Identity parameter.
Replaces any existing tel:PAI headers with the tel:PAI headers you configure with the P-Asserted-Identity parameter.
The SBC retains any existing tel:PAI headers or sip:PAI headers at the bottom of the PAI list that are not replaced by P-Asserted-Identity tel:PAI or sip:PAI values, as above.

Example configuration syntax includes:

ORACLE(realm-config)# P-Asserted-Identity sip:MyPai

ORACLE(realm-config)# P-Asserted-Identity-For INVITE, BYE

Examples

Example 1—When you configure the P-Asserted-Identity as a TEL URI and there is a tel URI PAI header in the incoming message, the SBC replaces the incoming TEL URI with the PAI header configured in the P-Asserted-Identity parameter in the egress messages specified in the P-Asserted-Identity-For parameter.

Incoming PAI: tel:56789
P-Asserted-Identity configured: tel:12345
P-Asserted-Identity-For: INVITE
Output: Egress PAI: tel:12345

Example 2—When you configure the P-Asserted-Identity parameter as a TEL URI and there is a SIP URI in the incoming message, the SBC inserts the SIP URI with the PAI header configured in the p-asserted-identity parameter in the egress messages specified in the P-Asserted-Identity-For parameter.

Incoming PAI headers: sip:123@oracle.com
P-Asserted-Identity configured: tel:12345
P-Asserted-Identity-For: INVITE
Output Egress PAI: tel:12345 sip:123@oracle.com

FQDN Hostname Manipulation

Additional configuration allows you to modify the hostname used in SBC response headers.

Some deployments need you to specify a hostname value in specific headers. You can configure the SBC to make these changes using two realm-config parameters. You can configure the system to apply your hostname to the following SIP headers:

FROM
TO
CONTACT
RUI

You specify a desired hostname value by configuring in the fqdn-hostname parameter with the desired hostname. Furthermore, you specify the headers you want to change using the fqdn-hostname-in-header parameter. If either of these parameters are empty, the SBC does not set this hostname in any headers.

Example settings for these parameter include:

ORACLEORACLE(realm-config)# fqdn-hostname MyHostName

ORACLEORACLE(realm-config)# fqdn-hostname-in-header FROM, TO

Configure Manipulation Attributes on a Realm

In the SBC ACLI, you can access manipulation parameters applicable to surrogate agent operation using the path media-manager, realm-config.

To configure targeted manipulation parameter on the SBC:

In Superuser mode, type configure terminal and press Enter.
```
ORACLE# configure terminal
```
Type media-manager and press Enter to access the media manager-related objects.
```
ORACLE(configure)# media-manager
ORACLE(media-manager)#
```

Type realm-config and press Enter.

ORACLE(media-manager)# realm-config
ORACLE(realm-config)#

Create or select the realm-config on which the softswitch resides.
P-Asserted-Identity — Enter the string you want to use to set the identity within PAI headers for traffic egressing this realm.
```
ORACLE(realm-config)# P-Asserted-Identity MyPAI
```
P-Asserted-Identity-For — List the methods for which the SBC includes a PAI header using the PAI identity you set in this realm's p-asserted-identity parameter. Separate multiple values with a comma.
- INVITE
- BYE
- ACK
- REGISTER
```
(realm-config)# P-Asserted-Identity-For INVITE, BYE
```
fqdn-hostname — Enter the hostname you want to in include in the selected headers for this realm's egress traffic.
```
ORACLE(realm-config)# fqdn-hostname MyHostName
```
fqdn-hostname-in-header — List the headers for which the SBC inlcudes the hostname that you configured in the fqdn-host-name parameter. Separate multiple values with a comma.
- FROM
- TO
- CONTACT
- RURI
```
(realm-config)# fqdn-hostname-in-header FROM, TO
```
Type done to save changes to this realm-config.
Save and activate your configuration.

Configure the applicable local-policy. This configuration includes setting the auth-user-lookup parameter in the applicable local-policy-attribute with the same value as the auth-user-lookup above.