ISDN-TEI

[johnleeee]

Hi all,

I have question about ISDN-Terminal Endpoint Identifier. I have no big experience with ISDN and I never experienced to troubleshoot ISDN but Im interested in this problem about TEI. So my question is when I will

instal BRI port(2B channels) into my router I obtain only one TEI from switch in Telco side for my BRI or two different TEIs for each B channel.

And another question is what about PRI interface?

I know that for PRI is TEI=0. But there is 30B channels.

many thanks

jl

[tepatel]

In case of BRI, Telco will sent unique TEI for each channel. So two TEIs for BRI line. Here is the link which explains about how the TEIs (IDs) assignments will takes place over BRI line

http://www.cisco.com/en/US/tech/tk801/tk379/technologies_tech_note09186a0080094b77.shtml

Telco uses those TEI numbers to inform user side equipment about which channels should answer the call.

In case of T1/E1 PRI, the TEI=0 because Channel ID is used to indicate the equipment (router or telco switch) about which channel should answer the call.

[johnleeee]

Thanks guy for advice.

I have one question besides.

When I have router with BRI interface

connected directly to our company PBX will PBX

send TEI or BPX will transparently send information (TEI) from telco switch to our router.?

rg

jl

[tepatel]

It all depends on how the PBX works. Some PBX emulates as a isdn BRI switch for all those bri switch-types. So in that case TEI will be sent by PBX.

You need to talk to PBX vendor or search for the specs. for that model of PBX and see how that works

So in either case, as far as router is concerned, PBX will act as switch.