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Using VoIP to Connect Phones Between Offices?
virtualPhoneWire asks: "My office is expanding to include a new facility which is just a few hundred feet just across the parking lot. The building is just far enough away to make running cable a pain in the neck, so to get data over there, we're setting up an 802.11b link, and a couple of simple Linux routers to handle the traffic, no problem. Now, the people in this new building are going to need access to our phone system, a simple Avaya Partner II key system. I would like to think that there is a way that I can patch them into our switch using some kind of
VoIP technology. The ideal being that we can issue a couple of IP phones that plug into the Ethernet back-bone, take their queue from my DHCP server, and linkup with a device on the other end that ties them into switch thus giving them access like any other phone. As an after thought, being able to give other people on our network, both inside the building and via our VPN, access to this gateway to
make calls would be a real bonus. We're considering an upgrade to a real PBX, but we would like to do this without blowing the pension plan. We would like to having something scaleable, and open source, if possible. Any thoughts?"
Call your system vendor. They will most likely tell you there is nothing that can be done :).
I looked at some voip quotes recently, one of the systems required lisences to be bought to use the phones over IP. Something like Four thousand for 10 phones. I think avaya has a module you can put in to your rack, and plug into your switch (its designed to also do power-over-ethernet injection. Be aware, the phones are going to cost you an arm and a leg.
On a second thought, buy two channel banks from adtran, they will take the voice channels to IP, then you can kick it over a wireless link.
this will cost like 1000 usd.
normally, a channel bank will go for 400-600.
I used to work for a company that did solutions like that. What we normally did was use ISA Micom cards (FXS). Micom are now owned by Nortel, and last I checked there were thousands of these cards still available through distributers. If you want to roll your own solution, get a rackmount case witha failover power supply, and a small processor ~ 266. Load the _DOS_ software and assign IP's,etc. Tie it into your existing PBX as trunks, and you are set.
If you are not inclined to roll your own, I do recommend Nortel's solutions, quite possibly because they tended to be the most relaible to use.
--Mike--
So, what would it take to make this a wireless solution? Would regular 802.11 do it?
What those who want activist courts fear is rule by the people.
Check www.digium.com.
They are the makers of Asterisk PBX and they'll probably have a solution for you. Going the IP phone route is probably more expensive, unless you have a small office and are _NOT_ planning to grow.
Two asterisk boxes and a channel bank would be much more scaleable and cheaper. RJS
The building is just far enough away to make running cable a pain in the neck, so to get data over there, we're setting up an 802.11b link, and a couple of simple Linux routers to handle the traffic, no problem.
What's with all this cabling talk? Never heard of a WAN?
Now, the people in this new building are going to need access to our phone system, a simple Avaya Partner II key system.
So how much would it cost for your phone co to hook this up?
I would like to think that there is a way that I can patch them into our switch using some kind of VoIP technology. The ideal being that we can issue a couple of IP phones that plug into the Ethernet back-bone, take their queue from my DHCP server, and linkup with a device on the other end that ties them into switch thus giving them access like any other phone. As an after thought, being able to give other people on our network, both inside the building and via our VPN, access to this gateway to make calls would be a real bonus.
You want to become your own phone company? Besides the initial investment costs, do you have the money to hire someone on to babysit the phone system?
We're considering an upgrade to a real PBX, but we would like to do this without blowing the pension plan.
Are your employees aware of how little money you have? Seriously, if you are expanding at a rate that requires you to lease new office space across multiple buildings, maybe you have enough money to leave this to the pros.
We would like to having something scaleable, and open source, if possible. Any thoughts?
Yeah. Don't skimp on the communications.
http://www.linuxtelephony.com/
Calling all phone phreaks. Business setting up voip and opening it to anyone sitting in their parking lot with a laptop and 802.11b wireless card. If encryption _is_ used, you may have to sit a while. ;-)
www.spectralink.com
...
I used to work there and they have various solutions in the VOIP space and have equipment that talks to various switches with both wireless and (I think) wired VOIP phones
A local business, not satisfied with the fairly meager loss in productivity when their wireless network is hacked, made a bold move and chose to make their phones depend on it too. A wise choice, this way their employees, when the network is down, really genuinely can't do much at all. Work is underway on a study that will somehow link the AC current to the wireless network. :-)
I work for a small private college and we have been looking at VoIP solutions. We are currently on a Centrex (sp.) setup which is basically a situation where we rent our lines from the phone company for a per month charge. No PBX or any similiar equipment. The solution is extremely expensive for 1200 phone lines (800 are inactive 4 months out of the year and are turned off to save $$ - dorms). We have looked at both VoIP and PBXs. VoIP provides consolidation of your voice and data networks which can be quite convenient. I have read of security issues with VoIP, but I cannot really say much about them without further study. The payback on VoIP vs. PBX is pretty substantial. VoIP payback 3 years, PBX 5 years. VoIP is easy to scale and grows with you pretty easily. PBXs require planning because if you buy too small a PBX and fill it to capacity, you have to buy another PBX with another 5 year payback when you may only need a few extra lines. VoIP doesn't have this problem.
Cisco bought a VoIP software company a few years back and has open sourced all of the software necessary to setup a VoIP solution on your own. The website is vovida.org. Also, O'Reilly sells a book (referenced on the vovida.org website) that describes how to use vovida.org to setup a solution.
You will still need to buy some hardware. VoIP phones or VoIP phone software will be needed for the new building. VoIP phones are between $200-???/unit. The phone software is cheaper and essentially gives you a softphone. There are free softphones for linux, for windows, you can purchase them for under $100 I believe.
I don't know how difficult to setup the free voip software is, it is probably best to pay someone to support a solution for you. Be sure to shop around, we encountered many subpar vendors. Also, PBX solution providers get pretty cooperative when you start talking about VoIP. It really depends on how many phone lines you require and what your future plans are. If you planned on upgrading your data network or expanding, VoIP can fit nicely into those plans. But if you only need to add 10 phone lines, then it would seem kind of drastic unless you are going VoIP company wide. Since we lease all our lines and want to upgrade our data network anyway, VoIP will save us alot of $$$. The quicker payback also saves us alot of $$$. The scalability also saves us alot of $$$. We can just buy what we need.
You just need a way to get a few lines over a wireless link from the sound of it. I hope this helps a little.
Maybe you could patch something together from vovida.org for those few lines. Check it out.
The security of your wireless network is essential. You have to linux routers setup at either end. You may have done so already, but don't depend on the WAP builtin to the wireless cards. It is easily circumvented. You strong encryption on the router-router connection. Perhaps obvious, but I would rather state the obvious and be sure you are aware of the matter.
If you only need two or four ports, grab a Cisco 2600 of 1750 off of ebay, throw in two of four FXO ports, and connect the FXO ports to the extension ports on your Lucent switch. Set up SIP on the IP phones in the "remote" office, and Bob's your uncle. Keep in mind that the Lucent Partner II requires switchhook action to transfer calls, and answer a second line. Using an IP phone might make that a bit difficult.
If it were me, I would run cable.
If you can't figure out my address, just drop me an e-mail and I will explain.
Something to keep in mind: For real time speech quality, wireline TDM bandwidth = 0.15 * IP Bandwidth. Meaning that a 100 Mbps Ethernet link can support approximately 10 T1 lines worth of voice calls (120 simultaneous full duplex conversations). This is based on Ethernet realizing a 33% average throughput on shared media plus allowing 100% headroom for equivalent quality after IP packetization and quantization.
If the throughput of wireless Ethernet is the same as wireline, and by throughput we're not talking about the burst speed of the link, then an 802.11b link should be able to support one T1 worth of voice channels, or twelve simultaneous conversations. If RF interference reduces the throughput, your mileage may vary.
Another alternative is to lease a T1 qualified two twisted pair copper line between the two buildings from the phone company. Other posts are mentioning using channel banks at either end of the line. With leasing, the cost and pain of digging et al belongs to the local phone company. It may be worth the monthly rate for 100 feet to avoid that.
Or, if the call rate is low, a cell phone could work...
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"Don't go the hard way.. Just set up a QSIG link into your favourite Cisco router and bind the GRE tunnel between the two QSIG links over the WAN or LAN via whatever method you choose.
I have installed around 40 PBX PBX systems this way and its so easy because all newish PBX systems support QSIG
`find / -name "*your_base*" -exec chown us:us {} \;`
--note I am talking out of my nether regions here. My thought is, is there some way to use a precisely aimed laser to carry the traffic rather than a broadcast radio solution? Please excuse if this is incredinly lame, it is outside my area of expertise. Just thought I'd throw it into the discussion as perhaps someone who is aware of this technology might expound on it to a small degree.
Well if your going to go wireless between the buildings, you might as well spend the extra couple hundred and use 802.11a. The spectrum is much less used.
As for the VoIP solution, look at shoreline, they have a nice selection of VoIP solutions that use standard analog phones as well as soft phones.
I love wireless as much as the next guy (probably more since it has made me quite a bit of money), but if you are talking a 200ft run across the parking lot (probably your own parking lot, right?), then there is a LOT to be said for running a little piece of conduit with a couple pieces of fiber in it. Your workers will likely not be happy running VoIP and the network over consumer grade 802.11b equipment, not to mention the headaches that you will face with QoS or interfacing the IP phones into your existing system.
Unless you plan on replacing your entire phone system, you're probably going to have problems interfacing the IP phones with your existing stuff, and even if you can do that without trouble, you're going to get really stuck when you put it all on that 802.11b link and start having problems. By the time you get enough *good* wireless hardware and routers to handle the link properly, you'll have spent an awful lot of money. Also, as others have mentioned you'll have problems meeting fire and safety codes without land-lines over there anyway, and building-to-building calls would be free with local phone service anyway.
Anyway, my main point is that in the long run, it will not be cost effective to bridge the parking lot with wireless and VoIP versus a buried fiber "extension cord" type setup. If you were a mile away or running across a major street or something, it would be highly cost effective.
If you decide to go for it anyway, here's a couple of suggestions:
1) Don't think VoIP phones. Think VoIP bridges. A couple of channel banks on either end of whatever network link you have should allow you to interface remote phones directly with your PBX. Contact your vendor about it. Hint: Don't mention wireless; say ethernet and fiber instead. Adtran has some inexpensive stuff in this arena.
2) Don't think 802.11b. It's not going to cut it. Get something along the line of the WyLAN or Proxim equipment that's designed to be a point-to-point ethernet bridge. You'll get performance almost an order of magnitude higher than 802.11b with a something like the 12mb proxim system vs 11mb 802.11b. This is a very important consideration. Do not ignore this suggestion.
3) Put real routers at either end of your bridge. Do not rely on crap 802.11b linksys network bridges or something similar. You will need real routers to do the very important job of QoS. If you have voice running over the network, they MUST be able to properly prioritize all traffic. All of the inexpensive consumer wireless products that advertise QoS will likely be unsuitable for your applicaiton. Get some cisco equipment on either end and be happy.
~GoRK
For a linux-centric solution, check out the VoipBlaster, or more specifically, voip.ring.org and Fobbit.
For a ready-made setup, checkout Multitech's MultiVOIP
These units aren't the cheapest VOIP solution, but among the easiest. They come in FXO and FXS flavors, which means (check me on this) you can hookup one end to a phone company provided POTS line (FXO?) and extend that to a remote location (FXS?), or hookup one side to your PBX and another to a POTS phone at the remote office (both FXS?), or PBX-to-PBX (??), or whatever.
The have a demo. You call a toll-free number which rings into a MultiVOIP device co-lo'd at some ISP in Chillicothe, OH (I've been to Chillicothe - it's sufficiently remote to convince me that it would work beautifully over a half-decent connection). That device connects you to a (very nice, I might add) sales rep at Multitech.
I have implemented over a dozen different VoIP systems and I can tell you there are as many different ways to do it as there are vendors. MCK, MultiTech, Spectralink and others all offer various ways to get it done. One thing I have seen over and over in homebrewed jobs is this- they usually don't work because people try to put too many devices in the path. If you go over 100ms of delay your call is hosed. I have done VoIP over 802.11b for a national logistics company with awsome results. I can say this- you get what you pay for. Avaya is presently light years ahead of NorTel in this arena for sure. How many people are you trying to connect? Do you want feature transparency across the link or just dial tone? Do you want wired or wireless phones? There are many things to consider. If you are thinking of a nex PBX altogether- look at the Avaya IP Office. $$ per user is cheap and funcitonality would have cost 4 times as much just two years ago. IMHO.
Anyone know where I can get some 802.11 cordless phones? The only ones I can find are made by Symbol, but I know there has to be more out there.
I plan on using them with Asterisk and my 802.11 access point. Yeah, I know 802.11 isn't 100% reliable, but I have wired phones for that. I need some VoIP cordless phones.
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I know you probably have a substantial investment in your present phone system; but I think you should check out Altigen here. We have an Altigen system managing communications in our office. Our sys admin dropped a couple of VOIP cards in the box for long-distance communication with remote offices. Granted, the remote office needed a matching VOIP card, but any phone in our office, when dialing certain extensions, became VOIP phones. These phones are standard phones, too.
I'm pretty sure that your local telco can set up a "hardwire" connection between your two offices. I'm not sure of the terminology anymore, but I believe it to be exceptionally reasonable.
But, c'mon, have you considered the benefits of having cable draped across a 100' span? Christmas lights, anyone?
Clueless person alert!
What's with all this cabling talk? Never heard of a WAN?
MAN not WAN and 802.11b bridges are a pretty good way to do this in a campus environment where ripping up pavement isn't an option.
So how much would it cost for your phone co to hook this up?
How much would it cost in monthly interoffice calls each month is the more important question
You want to become your own phone company? Besides the initial investment costs, do you have the money to hire someone on to babysit the phone system?
It's called a PBX and since the majority of most offices traffic is internal it saves huge cash over POTS lines.
Are your employees aware of how little money you have? Seriously, if you are expanding at a rate that requires you to lease new office space across multiple buildings, maybe you have enough money to leave this to the pros.
PBX's often have large upfront costs that can be prohibitive for a small business because the chasis are designed for a much larger size then the client needs.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
If you are using H.323, get the GNU Gatekeeper, also known as OpenH323 Gatekeeper.
You. Have. Thirty. One. Thousand. Three. Hundred. and Thirty. Seven. Messages. Last. Message. From. "HAXXOR" At. Two. AM. To. Hear. Message. Press. One.
It's 10 PM. Do you know if you're un-American?
You have two options:
a) Hope that Avaya supports VoIP with Partner. I don't remember if it does. Back when I worked for Lucent BCS (Before it spun off to Avaya), VoIP was bleeding edge and Lucent was still developing their VoIP systems.
b) If Avaya doesn't support VOiP with their Partner systems, you'll most likely have to junk the Partner system and get a key system that does do VoIP.
a) is more likely, since I recall the Partner being reasonably expandable, albeit nowhere close to the venerable Definity - Its expandability has allowed the platform to survive for over 20 years and still be one of the best PBX systems out the. (Definity was one of the first implementations of hot-swappable hardware - Swapping circuit packs in/out of a running system was a favorite demo to customers when the system was first introduced.)
As another poster mentioned, the Definity (He refers to it as G3, which is just the current variant of the Definity platform) can be given VoIP capability. Not sure at what size company a Definity becomes justifiable - My company started at around 80-100 people at 2 locations and had a Definity, but that could be partly because of anticipated growth and the fact that it was a Lucent spinoff. We're now a part of a different large company.) We had direct dialing-by-extension between Warren, NJ and Columbus, OH via a VoIP connection. I believe we now have VoIP links to other company locations too.
retrorocket.o not found, launch anyway?
I'm really surprised that no-one has come up with a system where you can basically "extend" a phone's reach, using 2 Linux boxes & 2 voice modem cards.
Or have they, and I just haven't found it yet?
Matt
We use VOip in my workplace, which is a place of constant customer service phonecalls, and the problem with VOip is that it sounds like digital garble most of the time. We're constantly having 2 call people back on the "land line" Don't do it, for your own sanity and those of the other employees!