Ready to bring VoIP into your business? Getting pressure to implement it but trying to avoid it? Here’s InformationWeek’s five-point take on the state of the technology. On a similar note, the open source SIP service Ekiga.net now counts over 29,000 members.
Five Things You Must Know About VoIP
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Eugenia Loli
Ex-programmer, ex-editor in chief at OSNews.com, now a visual artist/filmmaker.
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I have been looking into VoIP vs regular PBX — particularly the Asterisk system.
In most scenarios, it seems cheaper to go with Asterisk and SIP/IAX phones and is much more powerful compared to PBX offerings (~20 phones).
On top of this, I get the ability to do VoIP routing, develop a least-cost-per-call routing plan, integrate the system with scripts to provide callers up-to-date automated recordings, etc..
The current PBX is effectively a black box requiring service calls (at $150 or more a pop) for things as simple as adding a new extension, moving an extension, etc.. Things that with Asterisk can happen automatically (moving an extension.. hmm … anywhere, in the world..) or via a simple webinterface (adding new extensions).
On top of this, is adding voice on the same network as data (saving of infrastructure cost) really adding THAT much overhead? Seems like most codecs are ~13kbps .. doesn’t seem like that much of a load on the internal LAN ..
Granted I HAVEN’T done this deployment yet but on this deployment, I was pricing it to be around $425/phone (hardware, asterisk configuration, servers w/PSTN interface cards, switches w/POE, battery backup, etc..) and with the ability to admin remotely, should drasticly reduce on-site calls/issues. I’m definitely interested in hearing of others experiences/rollouts.
You might want to keep in mind that a lot of IP Devices (your IP Phones and adapters) do signal broadcasting and they sometimes do flood the network. I am really not sure if they are supposed to be doing that. Cisco and 3COM phones don’t do it, but I have seen some other phones go nuts, pinging every computer on the network and causing havoc on firewalls. It doesn’t cause any damage, but there would definitely be some network congestion. Make sure that you have a good router, and if you are getting phones from 3COM or such, they do have facilities to prioritize the packets, and in that case, the router has to support that specifications.
It’s fairly straightforward otherwise.
I’d agree with you on the cost. It shouldn’t go more than that.
On top of this, is adding voice on the same network as data (saving of infrastructure cost) really adding THAT much overhead? Seems like most codecs are ~13kbps .. doesn’t seem like that much of a load on the internal LAN ..
Latency is the killer, not bandwidth. I’m in a small branch office using VoIP, 13 people on a switched 100Mb network running basically thin-client (citrix) to our regional data center so you’d think we’d have capacity to spare.
Our techs couldn’t fine tune the network settings enough to ensure pop and crackle-free voice quality, there’s a lot of crap that winds up on networks even when you think you’re controlling it. Of course if they spent the time to do it properly, networks sniffers, QoS settings and all that, they probably could have tuned it better but at the end of the day it was simply easier to throw in a new switch and run the phones on their own network. That’s the route many VoIP customers go for specifically that reason.
Heck, originally we were using an IP-based PBX extender hanging off of an existing PBX in our regional office, basically 20 or so handsets hanging off an IP connection to our remote PBX but with local lines installed. It was a bit of a complex setup and it was absolutely horrible; our own IT people, the vendor’s SE’s, and our service provider’s SE’s could not get it running reliably over the setup we had. The bandwidth was sufficient but our provider just could not lower the latency enough on our private connection despite the fact we were on a top-tier service level.
So we tossed that and went with our own local IP PBX running on a parallel switched network, and it’s a charm.
We also rolled out VoIP for internal call routing between all of our offices globally a couple of years ago, which works well enough and transparently through the legacy PBXes as well as the newer IP ones. We never bothered with localized call routing in North America though, because from studying our useage we were realizing enough of a cost savings with VoIP for internal calling, our LD rates were cheap enough dialing across NA that it just wasn’t worth the hassle of implementing least-cost routing for external calling as well. That’s just us though, may not be the same story everywhere, everyone’s requirements differ.
Two things, one poster mentioned 13Kb/s. That sounds like ass. If you want cellphone quality, go for it, but I would not recommend a low bitrate codec for a business. You’re going to be looking at one of the u-law uncompressed codecs, which are around 80Kb/s with overhead.
Second:
Our techs couldn’t fine tune the network settings enough to ensure pop and crackle-free voice quality, there’s a lot of crap that winds up on networks even when you think you’re controlling it. Of course if they spent the time to do it properly, networks sniffers, QoS settings and all that, they probably could have tuned it better but at the end of the day it was simply easier to throw in a new switch and run the phones on their own network. That’s the route many VoIP customers go for specifically that reason.
No need for a second network. All the decent phones have a built-in VLAN capable switch. You plug your desktop into the phone and both the phone and the PC have their own VLANs. Set your switch to prioritize the voice VLAN (even an old $300 HP ProCurve can do this) and the switch in the phone will prioritize the phone’s traffic.
On the WAN side is where things get dicey. But even Covad is now offering a dual-PVC SDSL and ADSL option that splits the DSL line into two “pipes” – one with priority for voice packets. When not using the voice pvc, the data pvc can snag bandwidth from it. There will likely be bigger T1+ providers offering similar solutions in the future. You DO want an ISP that will prioritize your downstream traffic in some way, as it’s too late to shape it once it hits your router.
If you just want to do VOIP between two or three broadband connected locations and never want to go offnet – sort of an old fashioned private line network – do you just need SIP phones that plug directly into the LAN? Do the SIP phones then take care of numbering and dialling?
No they don’t: SIP endpoints need a SIP server to register to.
Use Asterisk, that can even be installed on a WRTG router with custom firmware…
Peter, how different would it be from just using skype or MSN? If its going to be a private network, it would be easier to do it that way – unless you arent going to be connected to the internet at all. The SIP devices, still need to connect to the server to register, and to know which devices point to what.. so you’ll require a SIP Proxy somewhere in the middle.
Recently my company asked me to look into switching VOIP systems. We currently “borrow” a Cisco VOIP system, but we would like to have our own system for local managment and ease of administration. One product I was very impressed with was the 3Com NBX. With this system you get a lot of bang for the buck. It’s a great system for any small business. For 30 phones we were looking at, the cost would have been, with installation support, around $18,000. That’s $600/phone. The NBX comes with support for “voice mail, automated attendant, ACD, hunt/call groups, call detail reporting, computer telephony integration (CTI), PC-based visual voicemail/e-mail clients (IMAP4)”, QOS, etc. It can scale up to 1500 users/phones.
It’s definitely worth looking into if you’re a small shop looking for VOIP. This may be easier for some admins who don’t have time or knowledge to setup an Asterisk box.
Hopefully their quality has improved. I have to administer an older 3Com NBX system and it is flaky at best, but they’ve had a while to address the issues, so you may have better luck (my company doesn’t want to have a service contract on the system anymore because it is older, so I can’t even update the system’s software).
Our small company switched from POTS to Vonage 8 months ago, it’s great and we’ve never looked back.
google talk? netcat? free?