Important Unisys Problem Alert for CPCOMM

Knowledge Base: Other

Unisys released a Problem Alert for CPComm 4R1. CPComm 4R1 is not verifying the checksum on IP, TCP and UDT input packets. This could result in corrupted data being delivered to UniAccess.

The PLE is located at: (You will need a userid and password to access this site.)The text of the PLE is:

IP, TCP, and UDP checksums are not verified on input packets PLE (Problem List Entry) 18011506

Product: CPCOMM
Communications Platform
Component: CPCOMM
Date Prepared: September 30, 2003
Date Updated: October 1, 2003
Affected Level: 4R1
Customer Technical Bulletin: ALERT
Alert Updated on: October 1, 2003

The symptoms are difficult to predict. Checksum verification prevents data that was corrupted in transmission from reaching the user application. If the checksum is not verified, packets that should be discarded are instead passed to the application, with unpredictable results.

Technical Explanation:
The CPCOMM Checksum Offloading feature allows the checksum calculations and verifications to be performed by Ethernet network interface cards attached to a PCIOP K2 that is running microcode level 2.23.0 or greater. Due to a coding error in CPCOMM 4R1, the verification of IP, TCP, and UDP checksums is bypassed on all input, regardless of the network type, PCIOP type, and microcode level.

Resolution Details:
Resolution for Level: 4R1
Resolution Status: FIX RELEASED
Resolved with Change: 03032-03538-PCR
Resolved with Change: 03032-03547-PCR
Fixed in Release: CPCOMM-4R1

Knowledge Base: Other