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2851 Sufficient for PSTN Lab Router?

Soondubu

Hi All,

I'm currently piecing together the PSTN Router for my voice lab and wanted to run this by anyone that might have some insight. Will a 2851 chassis be sufficient? Let me know what you think, thanks!

-Soon

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Comments

Soondubu

Also if anyone has a better alternative, I would greatly appreciate it. Thanks!

Kelkin

A 2851 would work fine.. I have a 2811 as mine.

shodown

Yes people use way less.

Soondubu

Here's what i've picked up for it:
1x 2851
2x pvdm2-16
2x MEM2851-512D
2x VWIC 2MFT-T1

Kelkin

Is this going to simulate your WAN as well? If so you will need another 2MFT.

pitviper

I’m using a 2821 for my CCIE Voice lab PSTN and it’s more than adequate. I was using a pair of 1760s for a good chuck of the NP Voice studies.

Soondubu

Yes it is.

Soondubu

Thanks! Just ordered everything and just waiting for it to get here.

pitviper

PSTN, WAN, and Terminal server (2821) on the bottom. Pic was taken before it was completely cabled up, but it's simialr to what you are looking to do.

Working on the NP:Voice?

Soondubu

NICE! I wanted to get a rack but there's nowhere I could put one that big in my apartment without it being a complete eyesore. Yea, i'm shooting for NP:Voice.

pitviper

The open Skeletek racks are really nice if you haven’t checked them out yet. The full sized racks really aren’t meant to be used in a residential structure LOL I had to gut the basement due to flood, and was able to put a full rack down there before we started rebuilding. Now, it’s a part of the house (or would have to be sawsalled’ for removal!)

azaghul

I'm using an old 3725 for both PSTN and WAN, fitted out with a VOICE30 for the DSPs, 3 x 2MFT's (4 x E1, 2 x T1) and 3 WIC-2T's. Using a 7960+7914 as my PSTN phone...all works fine.

2821's as access servers? We've got a couple of 2911's at work for that...just seems so wrong, so many other/better uses they could be put to...but then I work for a state govt dept who don't work on home lab budgets...

samtm123

Hi all,
I am just trying to setup my voice lab.. and have 2851 for PSTN router. right now I having issues with setup WAN serial interfaces.. do I need HWIC-4T1 ?

pitviper

WIC-2Ts or VWIC2s are much cheaper - I guess it depends on how you want to connect the branches = with DCE/DTE cables, or T1 crossovers (which you can make).

Flyingput

CCIE v labs use WIC-2Ts for WAN connections. And WIC-2Ts are very cheap on eBay (less than $20 IIMC). For CCVP, no need to bother with them. Just connect all routers/phones/servers to a 3560 switch, done.

pitviper

Flyingput wrote: »

CCIE v labs use WIC-2Ts for WAN connections. And WIC-2Ts are very cheap on eBay (less than $20 IIMC).

Until you add a couple of 2900s that don't support them

dentry

Im doing my best to understand the PSTN/Branch connections. So I can make a T1 crossover to connect the PSTN Router to the Branches to simulate the voice PSTN ? Then to simulate the Frame Relay Wan (data) to the same branches from the PSTN router I would use a rj-45 pinned out to 1-2-3-4-5-6-7-8 ---> 4-5-3-1-2-6-7-8 ? I found this link that seems to explain what I am trying to determine https://supportforums.cisco.com/thread/2229626. I was not aware you could simulate frame relay on ethernet. This is starting to make a little more sense. Last question, would it make sense to stay away from WIC-T's if just starting to build a lab, as they will not be supported on 2900's ? Thanks so much guys I really appreciate the feedback.

shodown

1. Yes you would make crossover cables from HQ/Branch routers to your PSTN. The Frame Relay and PRI will have to be on T1's you cant' simulate them ethernet without getting extra equipment involved. Your best bet is to get 2 port VWIC2 cards. They can be PRI's and Data T1's on the same device. As you pointed out the 2900 won't support the older cards so you should skip those.

dentry

You guys are the best, love the support!

pitviper

Someone neg-reped me for help in this thread!?

dentry

Weird, I gave you and shodown a positive rating...