"Contiguous DCC domain"?

[aballant]

Hi,

I read that the CTM can only provision circuits on a 'contiguous DCC domain'. Can a DCC domain span multiple rings?

cheers,

Andrew

[songserm]

Yes, it can. You can have multiple UPSR/BLSR rings and be able to span a circuit across a DCC domain as long as there is a path to both ends, ie all rings are connected via SDCC.

[aballant]

How is the SDCC configured over multiple rings, i.e. how are connected together. I presume you need a routing protocol at each intersection?

[songserm]

The SDCC channels provide an in-band management path within a fiber rings, of which there are two interfaces—one for each side of the fiber. It's a point to point topology. Multiple SDCCs become multiple paths or even rings.

Using CTM or CTC, you can creat a circuit, so that a SONET frame (packet) know its way to the other end. The paths can be chosen from SDCCs you have in your SONET network. There is no need of routing protocols because a circuit is predefined. That's why we call it a circuit. You can think of it as a telephone network where a path has to be established before you can begin a conversation.

Here is a helpful link to this topic.

http://www.cisco.com/warp/public/127/Circuits/15454_circuits.html

Regards,

Chawarong Songserm