atcomsystems.ca/forum Forums VOIP Phones & IP PBX Networking 802.11a -- 54mps

I have come across a situation today that I have not run across and am not sure this is the right forum but I'll give it a try.

Currently I have a client that has 2 phone systems. I have a point to point T1 from building to building. It is configured as 12 circuits DID and the other half for data. There is a CSU/DSU that seperates my 12 voice from the 768k serial data. I also have T1 cards in both the phone systems handling the configured DID's. With that being said...

My client has a data guru that wants to do voip or piggyback our twelve channels on a 802.11a network. It would be point to point with "54 meg" of data between the buildings. These buildings are literally across the street from each other. I cannot run aerial and I cannot dig under the street, hence the point to point T1. It is a state road in the city of Chicago. In other words, about 20 city departments have to approve anything crossing the state road above or below.

This 802.11a connection would have 2 parabolic antennas pointing to each other creating the link. Sound logic! (in theory)

The data guy said I could hook my CSU/DSU RJ45 T1 feed into his equipment to get the same 1.5 meg feed with at least another 30 meg to spare (for him).

Other than the weather conditions, like heavy rain killing the the connection, will this work? Wouldn't the T1 need some type of IP addressing for the CSU/DSUs? I have yet to get the equipment specs.

I put my disclaimer in of "If the data guy is gunna guarantee it will work, I have no problem with it."

Has anyone done this? I have no interest in competing with this proposal but am looking out for the best interest of my client. From a cost savings, the payback would be less than a year.

Wireless point to point connections function exactly the same as copper or fiber point to point connections.

Many businesses have this problem, and use a wireless point to point T1 type product. 802.11a is less used, but much faster than the more common 802.11b... so I don't see any problem with the wireless protocol being used. As far as IP address assignments and what not. For Voice over IP -- yes, IP addresses and what not are needed as the entire point to VOIP is using internet protocol for telephones. I'm not sure what hardware you'd be using with your phone system to use voice over IP, that's where the actual question is. Any network, be it wireless or be it copper -- would raise the same question. What hardware do you plan to use?

If he's saying you can directly connect your equipment which is expecting a T1 with its voice channels, then I find that hard to believe. He would need to have some type of hardware that emulates a T1 circuit, most hardware of that type is used exclusively for the point to point connection, not something that just puts it on a network.

This doesn't sound like VOIP to me, this sounds like something else...

More clarification will be needed to properly answer this. I realize my attempted answer may be confusing, I'm just thinking outloud.

If this were an exclusive T1 -- sure, no problem, point to point T1s can be of any physical type -- but this sounds like he's converting your voice channels into some other packet form, and I'm curious to see how he plans to do that.

Let us know.

He originally suggested voip but that requires additional investment. We informed them we can't support it unless he provides the conversion equipment.

I asked if he could provide the solution of hooking our equipment to his. Basically plug and play. The way he answered wasn't convincing. Like you mention, if it was all voice i can see it working, kinda.

I basically want to plug in on both ends and let the cyber cloud do it's magic. I guess I need to get more info on the equipment before I can give my support.

Yes... without knowing how he plans to do this, I can't help either. Some voice to network conversio needs to take place here, or T1 emulation -- and I'm not seeing that.

yes VOIP sounds so cool to alot of IT guys. Too bad most of them don't really have a good understanding of what it takes to intergrate with alot of phone systems. I'm not sure what he was talking about with the bandwidth and having some left over for him. Where does the 30 meg come in? Sounds like your disclaimer is well warranted. If he just using the 802.11A connection as a wireless bridge, your not really doing VOIP. It is more a wireless point to point. You would probably need IP address for the antenee to talk to each other, but maybe not. I would definately do your homework on this one. Maybe even make the IT guys show you a working one is progress.

[This message has been edited by Z-man (edited April 12, 2003).]

Z-man has it on the wireless point to point issue, although IP addresses wouldn't be needed as an IP network wouldn't be present, simply T1 emulation.

Have this guy give you a complete rundown.

This whole thing becomes a bit complicated because this IT guy is in Denver, me being in Chicago. The guy wanted to do voip but I shot that down because additional expense would be needed for more phone equipment.

He is claiming a 54mps wireless transmission rate. He plans on using about 30mps. He says thats sufficient for him. He says he can provide me the equivalent of a T1 feed compatible with my equipment. Getting a feed from him doesn't mean voip.

I didn't think about asking where he has one in operation. That will definately be asked. Who knows, IF the customer goes for it and it works, I'll have a story to tell.

I think that's what we were implying, if he plans to provide you with T1 emulation over a wireless link -- then yes, that could feasibly work. How he would divide that bandwidth would require some type of managed switch, as well as some type of T1 emulation equipment.

Let us know... sounds feasible, just really complicated.

Hey A6. Let me know if you need some help with this in Denver. I work in Denver.