EPN <--> EPN <--> PPN Link?

[CommDude]

OK... here's a good one to light up some neurons... what we have: PPN <-T1-> EPN1. What we're looking for: PPN <-T1-> EPN1 <-fiber-> EPN2. Yes, that's connecting EPN2 to the PPN by way of EPN1. So, the connetivity will be EPN2 - fiber - EPN1 - T1 - PPN. I highly doubt this is a &quot;supported&quot; configuration. I think technically this can be done... question is how? First, there is the connectivity issue. Second, there is the translation issue. Anyone try this... successfully? Thanks!

 

[lopes1211]

If you are talking about a &quot;direct-connect&quot; 3 cabinet system, you need to form a loop with the fiber links. It sounds like today you have a PPN and EPN. The EPN is at a remote location via DS1-C and you want to add a second EPN to the same location. Your config would be PPN<DS1>EPN<fiber>EPN<DS1>PPN. -CL

 

[CommDude]

Not quite... . No loop. We have many T1 remoted EPN's connected to a G3r CSS. The question regards connecting a new EPN via an existing EPN. So, it is literally EPN2 connected to EPN1 via fiber, EPN1 connected to PPN via T1. Therefore, EPN2 is obtaining the archangel link by way of EPN1.

 

[lopes1211]

With CSS, NO. Every PN needs to be connected to the SNI carrier via fiber or DS1C. What is driving the need for the additional EPN? I don't see how your dream scenario would really fit any need. If you have enough BW between the PPN and existing EPN, can you not just add carriers or consolidate some circuit packs to make additional carrier space? If you do not have adaquate BW to the PPN, you would need the additional DS1C links anyway. What exactly is the requirement? -CL

 

[CommDude]

Good question. There are 2 scenarios where I see a benefit. First, a remote site &quot;B&quot; where an EPN is preferable to IP telephony due to survivability needs. Remote site &quot;A&quot; already T1 connected to the PPN is close to Site B, too far for copper, but not for fiber. Assuming that Site A to PPN T1 is not running at capacity, it would make sense to connect EPN B to EPN A thus taking advantage of the existing T1 from EPN A to the PPN. There is a cost savings by not running another T1 to Site B.

Second, Site A & Site B are 2 adjacent buildings. Both have T1 connectivity through different POPs to the PPN. The link from Site A to PPN goes down because of a CO issue. Having a standby fiber connection between EPN A and EPN B would be a nice business continuity feature.

This second scenario is the very scenario that prompted my question yesterday. I was looking for a quick solution to getting an EPN back up and working. I know all too well there are many other redundancy and survivability options... you can only propose so much, then it is up to the client to listen and implement. I did, they didn't, and there we were.

Avaya at one point said the EPNA-EPNB-PPN connectivity is technically possible but falls into the category of &quot;permissable, but not supported&quot;. OK, been there, done that... not always the most pleasant of experiences to be left on your own to figure out what can be rather complex issues. I wanted to see if someone else had come across this configuration and made it work.