PRI line issue

[Donald Rasquinha]

I am new to AV and i have been assigned to solve a problem of Polycom VSX7000 with PRI line connection ..the unit is showing that the line is faulty ie the yellow indicator is on..

The PRI fiber optic line from the serice provider is terminated and converted to be given to a siemens Hipath 4000 EPBX system by mtnl whose the service provider.There are 4 such PRI line which is been used for the EPBX .We have been given one of this line by disconecting from the EPBX ,to use for the VSX7000 Polycom PRI line unit.
The Clock could be a issue ,since the polycom unit required a line with an external clock to be used .So we had to know if the PRI line was clocked from the service provider ,the information about the line came from a siemens technical person, that the mtnl line is clocked and which is used for the EPBX system.The PIN configuration for RJ-45 connector is used correctly ie 1,2,4,5 all combination were tired.

Second thing i wanted to know that There is no NT box at the site for the PRI Line its been connected directly to the polycom ....i doubt this is the problem...can any one who has installed a PRI line to VC unit confirm it.. please rely as soon as possible

[senthil]

generally PRI will comes with Modems not with NT. If you are talking about BRI then u need a NT eventhough if u configure in EPBX then no need NT u can mux lines and directly connect the BRI lines in the Polycom unit.
Let u confirm ur going to use PRI or BRI?

I configured MTNL lines in PRI for ISDN GW and i didn't find any problem.

Senthil.

[Donald Rasquinha]

we r using a PRI line which is given from the modem to our polycom unit..and about the NT box,I found that for a PRI line an NT is not reqired.

[senthil]

as you said you were removed the working line from the hipath right?.
there is no clock issue at all and there is no seprate confiuration for video or voice.

I think u have wirtten about the changing orders of wire for TX/RX ? and if u need a wiring diagram for vsx 7000 send me mail i will forward to u and u can try once.

Cheers

Senthil

[Donald Rasquinha]

i have the wiring for it too...form polycom a/v integrators manual....i tried all the configuration its 1,2 and 4,5 still it show the line is faulty..

[Donald Rasquinha]

whats a CSU/DSU (Channel Service Unit/Data Service Unit) device ,the Polycom tech support mailed saying that it is used to terminate a PRI line .
i want to know if is it used ...coz the mtnl guy is saying that there no such device reqired for a PRI line it is given directly.
I spoke to a person who deals with PRI line he said that a modem is used between a PRI line and the TE ....
is the modem the CSU/DSU device.

[senthil]

DSU/CSU

A Channel Service Unit connects to a telephone company-provided digital data circuit, and a Data Service Unit provides the electronics required to connect digital equipment to the CSU. Paired together a DSU/CSU allows computer equipment to be connected into the telephone digital service for highly conditioned, high speed data communications.

I think the above explaination will help u to know. See in simple term like how we are connecting the leased circuit the same way to connect PRI also. But in PRI we will use instead of V.35 modem we will use RJ45(E1) modem.So the connectivity between Modem and the Polycom.Check the line is working ? and also find out its connected in the modem or DLC? as you mention the client has 4 lines thats y i am asking.

Thanks

Senthil.

[vbhere]

You need a CSU/DSU type device to terminate your PRI circuit. I suggest an Adtran device such as an Atlas-550. The PRI plugs into this box whcih then connects to the Polycom

[Donald Rasquinha]

Hey Thanks dude for the the replies....i wanted to know who should provide the CSU/DSU unit ...is it the service provider or the system intergrator since mtnl says that theres no termination or devices to be supplied with the PRI line.....

[senthil]

The client needs to buy the CSU/DSU unit and MTNL will not provide.

Senthil

[cfaasen]

We have used the Adtran 550. Do you actually need all that badwidth ? You can divide to multiple CODECs.