Calling all IT professionals...WAN question

[Aragorn]

OK,
Here's the scenario:
I'm designing a WAN(easy nuff) to "tie" 3 medical offices together. I'll be moving Data and Voice between all 3. Normally I'd use a T1, channelize the voice and the data and break it out on the other end. However, I'll be deploying a new phone switch that incorporates VoIP(Voice over IP). Therefore, any "voice" calls between the offices will be sent as data packets. Still no problem. I guess my question is:

Has anyone setup a WAN incorporating VoIP over DSL and cable? I have not. I've always used Frame Relay and/or fractional/full T1's etc. The WAN will be static addressing, of course. I'm just concerned about bandwidth considerations. The office here in Tahoe I can setup w/ HDSL(1.5Mb downstream, 6Mb upstream). The other satellite offices(much smaller) have only cable available. If you have any pro's and/or con's I'd like to hear it. Thanks.

[schrocat]

Aragorn,
Somebody sent me notes today which might cover some of the stuff you want. I'll dig Monday.
We are also setting up voip (I think to transfer between campuses and to route to some Nice phone logging servers)
I'll check and see if they're are any usable stats.

How many users?

[Aragorn]

Schro-

Bout 20 in the main office here in Tahoe, 10 in the satellite office in Minden, and only 3 in the office in Incline Village. I'm designing in Nortel switches that will route interoffice calls(all phones within the 3 offices) over the Internet. Any calls to the "outside" will be over regular telco lines. I'm incorporating dedicated 56K "fall back" circuits in case the DSL or cable fails.

[ravenmore]

Dude - I really don't recommend voice over IP - my friend is a network engineer at a company that uses it and its giving them a lot of headaches. Lot of echoing and breakups. My impression without looking into it hardcore is that it is a bandwidth hog. I think they have t1's between the offices....I'll have to ask. But basically bandwith spikes affect the quality of the transmission. I distinctly remember he mentioned network print jobs affecting the quality of the calls.

If you get it working well for you, I'd be interested to know as well as some of the details as to how you got it to go.

-Mike

[Aragorn]

Well I have set these Nortel Enterprise Edge's up in a Lab environment and have personally used and tested VoIP. Works well depending upon the compression. But that's the lab, not the real world. Unfortunately I don't have a choice in this matter because the customer has already signed the quote. As usual, the Salesperson didn't bother to get the Engineer(me) involved in the discussion. You should see the Visio diagram she created. Totally wrong. It's up to me to design it and deploy it. I've got 1 month until the "roll-out". I'm sure I can get it working. I'm just not sure about over HDSL and cable. I'm definitely upgrading the LAN infrastructure(s) to managed 10/100 switches. I'll let you know.

[schrocat]

Ravenmore may be right...
We're running 2 45mg pipes between us and the mother ship.

But that seems like such few users.

later,

[Aragorn]

With managed switches, I will probably create VLAN's in order to segregate network traffic. Trust me, I'm not convinced VoIP is ready for "Prime Time" yet either. Again, I don't have much say in the matter...the customer has already signed on "the dotted line". And unfortunately everyone at the corporate office think I'm some kind of "miracle worker" and that I can make it happen(hear that Lord? ). It's nice that they have faith in me, but I just wish I would've been brought into the loop earlier. I could've then recommended an alternative solution. One thing in my favor is that these Nortel switches appear to work quite well...as long as you have the LAN configured properly, thus VLAN's and such. Additionally, I will have signature authority by the customer and corporate to get any hardware and circuit(s) I need to make it happen.

[ravenmore]

I emailed the friend of mine in question and invited him to look at this thread.

Side note: I've often thought a bulliten board for computer/technical issues would be a valuable resource. Do you guys know of any? If not, do you think it'd be a good idea to start one?

-Mike

[schrocat]

ravenmore,

Window$ www.techrepublic.com

For unix www.slashdot.org

I subscribe to a ton of newsgroups, mostly for the BSD's...there are tons...
Download Gravity for that action...
these are some hot ones (comp.unix.bsd.freebsd.misc)
(news.admin.net-abuse.email)

ACT NOW!!
And you'll also recieve
at no extra charge!!!! (rec.aquaria.marines.reefs)

[FishTechie]

just a note to maybe solve the bandwidth spike problem. you may want to consider intalling a Packeteer box which will allow you to allocate badnwidth any way you want...hth

[ccull]

VOIP actually uses very little bandwidth, it is VERY latency and jitter dependant though. Basically it wants about 64kbs of very stable and consistent bandwidth (that 64kbs can vary based on what you're using, but it shouldn't go much above that. We have one codec that uses only 20kbs). My only concern with xDSL would be the consistency of the latency. On our switched 100mbs network at work we actually daisy chain our pc's off of our phones: IE the pc is using the exact same 100mbs port as the phone; and it works great. Anyways, this is coming from a guy who has not only set this stuff but also uses it on a daily basis. HTH