Field Notice: T3 Port Adapters May Not Provide a Two-Second Delay Before Bringing Down the T3 Controller

October 05, 2004

---

Products Affected

Products
7202 - PA-2T3+
7204 - PA-2T3+
7204 - PA-MC-2T3+
7204 - PA-T3+
7206 - PA-2T3+
7206 - PA-MC-2T3+
7206 - PA-T3+
7500 - PA-2T3+
7500 - PA-MC-2T3+
7500 - PA-T3+
7505 - PA-2T3+
7505 - PA-MC-2T3+
7505 - PA-T3+
7507 - PA-2T3+
7507 - PA-MC-2T3+
7507 - PA-T3+
7513 - PA-2T3+
7513 - PA-MC-2T3+
7513 - PA-T3+
7576 - PA-MC-2T3+

Problem Description

The port adapters listed in the Products Affected section above, bring the T3 controller down immediately after receiving one of the following alarms on the wire: LOS or AIS.

Background

Based on the ANSI T1.231 specification a T3 controller should not react to an alarm (LOF, LOS, AIS) unless the alarm persists for 2 +/-0.5 seconds. The T3 Port Adapters (PAs) listed above in the Products Affected section do not adhere to the failure declaration specification threshold.

Problem Symptoms

Since the T3 PAs listed above in the Products Affected section do not adhere to the two second holddown timer before reacting to an alarm as defined in the ANSI T1.231 specification, the controllers will go down immediately and come back up a few seconds later. This will result in loss of data and interference with user traffic.

Workaround/Solution

Workaround:

None

Solution:

Upgrade IOS to a version that resolves the failure. Please view the Bug ID provided below for the respective PAs that correct the failure.

Port Adapter	DDTS
PA-MC-T3=	CSCee49862
PA-MC-2T3+=	CSCee49862
PA-T3+=	CSCee70591
PA-2T3+=	CSCee70591

IOS releases with fix for the PA-T3+ and PA-2T3+:

12.2(26.09)S 12.1(23.02)E 12.0(29.03)S 12.3(11.01)T 012.003(011.001) 12.2(24.08)S03

IOS releases with fix for PA-MC-T3+, PA-MC-2T3+:

12.1(23.01)E 12.0(29.01)S 12.3(09.07)T 12.2(24.08)S 12.2(24a) 012.003(009.007) 012.002(024.008) 12.2(19c)

DDTS

To follow the bug ID link below and see detailed bug information, you must be a registered user and you must be logged in.

DDTS	Description
CSCee49862 (registered customers only)	PA-MC-2T3+ does not adhere to ANSI T1.231 standard
CSCee70591 (registered customers only)	PA-2T3+ does not adhere to the ANSI T1.231 standard

For More Information

If you require further assistance, or if you have any further questions regarding this field notice, please contact the Cisco Systems Technical Assistance Center (TAC) by one of the following methods:

• Open a service request on Cisco.com
• By email
• By telephone

Receive Email Notification For New Field Notices

Product Alert Tool - Set up a profile to receive email updates about reliability, safety, network security, and end-of-sale issues for the Cisco products you specify.

---