DWDM transponder Y cable protection

[Mark Pace Balzan]

Hi,

I have a question about the use of a Y cable for redundancy on DWDM point to point links.

Basically the topology Im looking at is having the 'hands' or the short ends of the Y each connected to the client port of a transponder card, and the 'stem' or the longer part of the of the Y connected to the client port of the end device, a router. This will happen at both ends of the link, so in this way I will be protecting against transponder card failure. Of course this does not protect against router failure.

like so:

ROUTER_A---<(2 x TXP)====wavelength====(2 x TXP)>---ROUTER_B

The question is: Is it possible for the transponder cards to be in separate chassis, and the Y cable connecting to these transpoder cards in the separate chassis, such that I achieve chassis protection, in addition to Transponder card protection ?

Also since the Y cable divides the power of the optical signal, how best to verify that my system can handle the attenuation of the signal from the Y cable ?

thanks

Mark

[Tom Randstrom]

In order to use the Y-cable, you will need to create a protection group for the two transponder cards in the CTC management software. The protection group allows the system to select the transponder card interface that should be active.

Thus, the transponders need to be part of the same MSTP system; which could be either a single chassis or a multi-chassis system. But, the Y-cable protection group cannot be made across MSTP systems (independent chassis').

The following documents outline some of the specifics.

Reference Guide

<http://www.cisco.com/en/US/docs/optical/15000r9_0/dwdm/reference/guide/454d90_txpmxpcard.html#wp1145661>

Procedure Guide

<https://www.cisco.com/en/US/docs/optical/15000r9_0/dwdm/procedure/guide/454d90_provisiontmxpcards.html#wp341035>

I hope this helps.

[viyuan700]

"so in this way I will be protecting against transponder card failure. Of course this does not protect against router failure. "

There are options where you can have client protection. Needs to be checked for Router and interface you are using.

Something like this for your system

he Layer 2 XPonder also supports "Y-cable bidirectional-like" switching where two cards in 1+1 protection are connected through a Y-cable to a single client*.

The question is: Is it possible for the transponder cards to be in separate chassis, and the Y cable connecting to these transpoder cards in the separate chassis, such that I achieve chassis protection, in addition to Transponder card protection ?

Yes you can have in separate chasis but those different chasis are to be managed as single node.

Also since the Y cable divides the power of the optical signal, how best to verify that my system can handle the attenuation of the signal from the Y cable

For every card there is receive power level. once you connect Y cable to the client port check the Output power at both Y ends which you are going to connect. See if that power is within the limits. Dividing the power here will not be a problem as we are talking about small distances.