PRI slipping with 2 clock providers

[fadi2008]

Hi all,

A customer has 2 Option 11C PABXs, located in 2 different places. These 2 PABXs are linked to each other with a PRI card. An ISP provides both sites with the clocking. The PRI was working well until a new PRI was installed between one of these 2 sites and the PSTN provider. At that time, one of the 2 links suffered from slipping that led the E1 to go down. This is logical since we have 2 clock providers (ISP and PSTN provider) and no one of these 2 providers can put his system as transparent, of course talking clock wise, so we come up with only one source clock.

Is there any solution for the above issue????

Please this is very URGENT!!!!!!!

Thanks in advance...

 

[telebub]

To make sure I understand, PBX A has a PRI to the PSTN and a PRI to the other Option 11. PBX B has a PRI to the other Option 11. Is this correct? If so, change your clock on PBX A to go to the PSTN and keep PBX B clocking off the Tie Line.

War Eagle!
Lions Baseball '09!

 

[fadi2008]

No there are only 2 Option 11 PABXs:

1- A is linked to B with a PRI and to PSTN with another PRI

2- B is linked to A

 

[pronei]

That is what telebub said.. anyway to make it clear. I am assuming you have the TMDI cards.

In PBX A (TIE PRI to PBX B & PRI to PSTN)
Make sure you have the TMDI card that has the NTAK20 (Clock Controller Daughterboard) connected to the PSTN. Change your DDB in LD 73 to make CC0 = PSTN PRI Loop. Delete SREF's to PRI = TIE to PBX B.

In PBX B (TIE PRI to PBX A)
Make sure you have the TMDI card that has the NTAK20 (Clock Controller Daughterboard) connected to the TIE PRI. Change your DDB in LD 73 to make CC0 = TIE PRI Loop. Delete any SREF's in the DDB.

In LD 60 on both PBX's, after the loops are back in service, type "trck pck" (Track on Primary Clock Controller) wait up to 5 minutes, then "ssck 0" make sure you are in a Tracking or Locked state on the correct loop that was defined in LD73.

If you still are getting slips after this, you'll need to contact your LEC.

 

[fadi2008]

let's explain it again:

Before the slipping appeared, we had two option 11 PABX A & PABX B:

PABX A has 2 PRI, one with PABX B and one with ISP(ISP has a free run clock)

The slipping appeared after we added a pri on PABX B which is connected now to PSTN( PSTN also have a free run clock)

the issue is how to synchronize everything while we have 2 providers (ISP &PSTN) with each one of them have their own free run clocks ? ? ?

 

[pronei]

You dont want free run clocks, do as I posted and you'll be fine.