Configure SDP Transparency Profiles

SDP Transparency Profile Overview

SDP Transparency Profiles contain a set of rules for declarative SDP attributes that allow the system to pass through declarative attributes that are not natively supported by Unified Communications Manager from the ingress to the egress call leg. Without an SDP transparency profile, Unified Communications Manager drops non-supported SDP attributes.

You can configure SDP transparency profiles with multiple rules and apply them to SIP devices via the SIP profile. In order for the SDP transparency profile to be applied, both call legs must be SIP. You can configure the following types of rules for SDP attributes:

  • Property—If a rule is configured for a property attribute, Unified Communications Manager passes through the SDP attribute unless the attribute has a value.

  • Any Value—If a rule is configured for any value, the SDP attribute gets passed through so long as it has a value that consists of at least one non-white space character.
  • Value From List—If a rule is configured using this option, the SDP attribute gets passed through so long as it matches one of the specified values. You can configure up to five possible values

SDP Transparency Profile Restrictions

The following restrictions apply to SDP transparency profiles. If any of these situations occur on the egress call leg, Cisco Unified Communications Manager will not pass through the declarative SDP attribute:

  • One or more Media Termination Points (MTPs) or Trusted Relay Points (TRPs) that do not support passthrough are allocated

  • The Media Termination Point Required check box is checked for the SIP trunk

  • A transcoder is being used

  • RSVP is being used

  • The ingress call leg is using Delayed Offer while the egress call leg is using Early Offer

  • The media line has been rejected (port=0)

  • Either call leg is using a protocol other than SIP

SDP Transparency Profile Prerequisites

If you plan to deploy any third-party SIP products, make sure that you understand how the products implement the Session Description Protocol (SDP).

Configure SDP Transparency Profile

Configure a customized SDP Transparency Profile with a set of rules for declarative SDP attributes that are not natively supported by Cisco Unified Communications Manager.

Procedure

Step 1

From Cisco Unified CM Administration, choose Device > Device Settings > SDP Transparency Profile.

Step 2

Click Add New.

Step 3

Enter a Name and Description.

Step 4

In the Attribute Information pane, create the rules for the SDP attributes that you want to pass through:

  • To pass through a property attribute, enter the attribute in the Name text box (for example, a=recvonly) and from the Type drop-down list, select Property.
  • To pass through a value attribute, enter the attribute in the Name text box (for example, a=rtpmap), and select Any Value from the Type drop-down list box.
  • To pass through a value attribute with any of up to five values, enter the attribute in the Name field (for example, a=rtpmap) and select Any Value from the Type drop-down list. In the resulting Value text box, enter the value of the attribute. You can click + to add up to five possible values for this attribute.

Step 5

Click the (+) to create new lines where you can enter additional SDP attributes for this transparency profile.

Step 6

Click Save.

Note

 
You must apply this profile to a SIP Profile so that the devices that use the SIP Profile can use the SDP Transparency Profile.