Bug ID 597835: Branch parameter in inserted VIA header not consistent as per spec

Last Modified: Nov 07, 2022

Bug Tracker

Affected Product:  See more info
BIG-IP LTM(all modules)

Known Affected Versions:
11.6.0, 11.6.0 HF1, 11.6.0 HF2, 11.6.0 HF3, 11.6.0 HF4, 11.6.0 HF5, 11.6.0 HF6, 11.6.0 HF7, 11.6.0 HF8, 11.6.1, 11.6.1 HF1, 12.0.0, 12.0.0 HF1, 12.0.0 HF2, 12.0.0 HF3, 12.0.0 HF4, 12.1.0, 12.1.0 HF1, 12.1.0 HF2, 12.1.1, 12.1.1 HF1, 12.1.1 HF2

Fixed In:
13.0.0, 12.1.2, 11.6.1 HF2

Opened: Jun 07, 2016
Severity: 3-Major
Related Article:
K12228503

Symptoms

MRF SIP in LoadBalancing Operation Mode inserts a VIA header to SIP request messages. This VIA header is removed from the returned response message. The VIA header contains encrypted routing information to route the response message. The SIP spec states that all messages in the same transaction should contain the same branch header. The code used to encrypt the branch field returns a different value each time.

Impact

Some servers have code to verify the brach fields in the VIA header do not change within a transaction. These servers complain when they see the fields change.

Conditions

-- Enabling SIP Via header insertion on the BIG-IP system. -- SIP MRF profile. -- Need to cancel an INVITE.

Workaround

None.

Fix Information

The system now ensures the branch field in the via header does not change.

Behavior Change