Correcting trunk issues between Dialogic CG Series boards

Symptom

A T1/E1 trunk is configured between a Dialogic CG Media Board to carry an SS7 timeslot. The trunkmon utility on the CG  board shows issues on the trunk, with FrameSync entries such as NoCRCF or NoFrm.

Trunk 1 and Trunk 3 in the sample trunkmon output below show this issue:

Digital Trunk Monitor NMS Communications Ver 1.5 Oct 24 2007 (Press F3 or ESC to exit, ALT-F1 to reset) BOARD # 0 ------------------------------------------------------------------------- Monitor start time: Tue Mar 17 16:36:54 2009 Alarms Remote Errored Failed Code Slips Frame alarms sec sec violations sync ------------------------------------------------------------------------- Trunk 0 NONE NONE 1 0 0 1 OK Trunk 1 NONE NONE 33048 33048 0 2 NoCRCF Trunk 2 NONE NONE 1 0 0 1 OK Trunk 3 NO_FRM NONE 39909 41412 0 21 No Frm

Reason for the issue

By default, a CG board is configured for Multi-frame CRC. This causes an issue if a T1/E1 trunk is connected between the two types of boards.

Fix / Solution

Add the following line to the CG board configuration file:

NetworkInterface.T1E1[0..3].CRCMFMode = C44OFF

After reloading the CG Series board, the trunkmon utility should show good Frame Sync.

Product List

Dialogic CG 6x6x Series Media Boards
Dialogic CG 6000 Series Media Boards

Glossary of Acronyms / Terms

CRC  -  Cyclic Redundancy Check - a checksum value placed in a transmitted packet to determine if a transmission error occurred.
trunkmon usage :
TRUNKMON Version 1.5   Feb 22 2009

usage: trunkmon [-@{server}] [-b{board}] [-l{loopback mode}] [-q {query loopback mode}] [-t {trunk}]

  -@{server}    - server host name or IP address, default = localhost
  -b{board}     - Board to monitor [default 0]
  -s                  - enable beep when trunk alarm state changes
  -l{mode}       - (diagnostic only) set loopback mode
                          mode = 0: no loopback - normal mode
                          mode = 1: line loopback
                          mode = 2: backplane loopback
  -q                  - (diagnostic only) query loopback mode
                   output in oammon (agtrace 0x1000 must be set for AG boards)
  -t{trunk}       - trunk number [trunk number 0 based, default 0]
  -?                  - shows this help