Ten things you always wanted to know about IP Voice

When I was a contractor building IT architectures, it was common to find that people had a rather old phone system and were looking to move to something newer. The question they asked was always: what shall we do to get something stable but future-proof? Phone lines or IP trunks? Even in 2015 you seldom see an organisation …

[Simple Si]

"If your phones can only do 100Mbps Ethernet and your users whinge that this isn't fast enough, tell them to get lost. Generally it is fine unless they are doing stuff like throwing high-res graphics and video around. If your phones can do Gigabit, you will have no problem."

Or, just add another gigabit network cable to the user's PC...

[Anonymous Coward]

"Or, just add another gigabit network cable to the user's PC..."

Which PC would normally be connected to the LAN via the phone...

[Nick Ryan]

Which PC would normally be connected to the LAN via the phone...

It's quite common for VOIP phones to connect to the PC's network connector and to have a "pass-through" connector to connect the phone to the PC. These phones are effectively 3 port network switches, with the three connections being 1) the wall socket, 2) the phone and 3) the PC. These network switches are usually 100, not Gigabit ports.

While this may sound an odd thing to do, it greatly reduces the number of network ports required although many sites have a socket for the phone and a socket for the PC in place already, it just depends on whether or not the phone socket can be repurposed as a network socket or not. You'd be surprised how many can't be!

[Lee D]

"Incidentally, I have had many clients and users moan over the years that the phone has been slowing down the PC. They were all wrong so don't fall for it."

I find the suggestion to just dismiss their concerns pretty amateur.

Login times, just for things like roaming profiles, etc. will be reduced BY A FACTOR OF TEN on gigabit. You don't need to have buckets of high-res video, just an ordinary press officer or marketing person will be dealing with gigabytes of photos in their average day.

100 is bare basics nowadays and covers all the bog-standard stuff, access control interfaces, etc. but Gigabit to the desktop is the norm an expected. If your phones can't handle it, it's time to junk the phones or run other ports - as suggested above - not ignore it.

I work in schools, most of them are VoIP-only, and I absolutely minimise the number of "passthrough" sockets I deploy precisely because it DOES affect the speed of login times etc. And in a school, you might have 20-30 people log onto a machine in the course of a day. A login being just 1 minute (and that's optimistic at best!) instead of 6 seconds makes for half-an-hour of wasted time over a day just through logging on.

100Mbps is NOT acceptable on new hardware. Legacy hardware, outliers on your IT plan (e.g. putting a phone in an out-of-the-way cupboard that only one person uses, etc.), maybe but not part-and-parcel of your desktop rollout.

Run more ports. Always run more ports. Don't "passthrough" anything unless you're sure it's going to last you.

[Michael Wojcik]

100 is bare basics nowadays and covers all the bog-standard stuff, access control interfaces, etc. but Gigabit to the desktop is the norm an expected.

Oh please. I only upgraded my home switches to 100Mb because the old 10Mb ones died. All the family's on wireless anyway, of course, and my wired machines pretty much never needed more bandwidth. And since I'm working from home, most of the traffic (including, yes, VoIP, desktop sharing, etc) is over the WAN, which means a VPN on top of a commodity cable ISP connection that's a few Mb/s at best.

In my younger days I worked on teams doing remote X11 over shared-media 10BASE-2 and 10BASE-T with a dozen machines in the collision domain. And we all managed to get our work done. Later I worked from a remote office with a 56Kb line and Frame Relay connection to the main office; and after that from a home office with 64Kb BRI ISDN.

Kids. Lawn.

[asdf]

10 things?

For VOIP home users at least in the US you need to know one thing. Magic Jack Plus (Raspberry pi like device, no PC required). $20 a year, can still use your regular phone and you have a home phone number (others can call) that can call any other North American number for free (900 numbers aside) with voice mail and even 911. Crystal clear as well.

[GarethB]

Needs better information on faxing

Trying to fax over a voip connection is a bit of a minefield. It can be done and works reliable over a good connection using G711. However using other codecs or a poor connection and it won't work.

You would be better off porting the fax number to a provider which offers a fax to email and email to fax service.

[Anonymous Coward]

Re: Needs better information on faxing

Or moving away from an ancient dying technology to something more secure and reliable?

I've never understood why companies are clinging to fax. It had it's time, there are far better ways to transfer data/documents without scanning an image of a slice of dead tree.

Even storage of those images is inefficient since the content is usually text and being an image means no editing/copy and paste without some flakey OCR middle-man.

[Anonymous Coward]

Re: Needs better information on faxing

You'd be surprised how many business still use Telex, and for good reasons, too.

[Roland6]

Re: Needs better information on faxing

>I've never understood why companies are clinging to fax.

Simple, I've sent a contractual document to a client that needs their signature before my team step on site. The easiest way for the client to read the document etc. is to print it out and use a pen to sign that copy and put it on to a fax machine, thereby transmitting a legally recognised copy back to me and knowing that I have received that copy...

There are other business use cases (albeit a small group), largely revolving around convenience and ease of use by non-tech people, where having a fax machine that can scan paper containing handwriting can be helpful.

But yes, as technology gets better we can expect traditional fax to disappear, something that the adoption of X.400 messaging (instead of SMTP) all those years back would probably have assisted...

[Anonymous Coward]

Re: Needs better information on faxing

"Simple, I've sent a contractual document to a client that needs their signature before my team step on site."

There is no reason this couldn't be done with a PDF and combi-printer/scanner without having to worry if the line is secure between you and the recipient.

But why bother with paper at all? PDFs can be setup to take the customers signature (signed from touchscreen or inserted as an image) and submit the signed document back via a secure web service entirely removing the need for paper.

This would also allow any systems at your end to take action on the submission from the web service and allow more automation of your own processes. For example auto-filing of the document instead of an employee retrieving and scanning the fax.

Like I said, dying technology and as tech. people, I think it is our responsibility to push these better ways of doing things.

[Roland6]

Re: Needs better information on faxing

There is no reason this couldn't be done with a PDF and combi-printer/scanner without having to worry if the line is secure between you and the recipient.

Fax isn't about 'secure lines' but about real-time push delivery of a hard copy facsimile copy of whatever someone wants to send in (potentially) a readable form by the recipient and confirmation of completion of this task that can be waved around in front of managers and if necessary before a court.

For lesser tasks then the fax service is not really necessary. From your implementation examples, I think you've become a little institutionalised in your thinking about how businesses work and the level of IT out-there. Yes there is lots technology can do and will probably do better in the future. However, I've found that being able to accommodate the use of old fashioned fax machines (which these days is typically an all-in-one combi printer/scanner) by clients, has done my business no harm and potentially a lot of good...

[Christian Berger]

Re: Needs better information on faxing

"But yes, as technology gets better we can expect traditional fax to disappear, something that the adoption of X.400 messaging (instead of SMTP) all those years back would probably have assisted..."

I doubt that with X.400 any of us could even afford E-Mail. I mean SMTP is so simple early servers even had a "HELP" command to explain the protocol to you. Now compare that to X.400 where you have a binary protocol based on ASN.1. The parser alone needs more code than a simple SMTP server.

[A Non e-mouse]

Re: Needs better information on faxing

Analogue lines aren't just used by fax machines: PDQ machines, Franking Machines, door intercom systems, security barriers, etc. These all need some form of analogue phone connection.

Fax/Modem/etc over VoIP is not as trivial as people make it out to be. The devil is in the detail.

[Anonymous Coward]

Re: Needs better information on faxing

I was referring to fax as the ancient dying technology, not analogue lines. Why are people trying to get fax working over VoIP instead of using a "modern" technology like (encrypted) e-mail or some SFTP service.

[Christian Berger]

Re: Needs better information on faxing

Well at work we are regularly conducting fax tests. And typically we get around 98-100% success rate for 10 page faxes (around 100kbyte per page) over T.38.

Fax over G.711 is heavily dependent on a pristine connection and high accuracy clocks on both ends.

We haven't tried analogue modems as that's largely irrelevant in Germany, but we have tried ISDN data connections (X.75) over VoIP. Those work rather well.

[Paul]

what was the purpose of this article?

it reminded me of one of those semi-useless blog-like sites which are set up to garner advertising revenue by publishing articles which use all the right buzzwords but don't actually provide any useful information.

[Anonymous Coward]

I was also a bit surprised by the slagging off of cheap overseas deals. I've used several and never had a problem with call quality.

I've found that they provide a good service, configure and forget. The users at two companies where I set it up don't even know there was a change. For them it was business as usual.

I'm sure that some cheaper providers aren't any good but that's clearly not the case for all.

[dogged]

what worries me is the assumption that CIOs need a "non-techies guide". If they need a non-technical guide, they should not be CIOs.

[Christian Berger]

Not the first one by that author

If you look at what else that author has written you will see that there is little thought in what he writes.

[Steve Evans]

No SIP app required on modern Android hand sets

The standard google Dialler can handle SIP perfectly since at least Kitkat. I've got multiple SIP accounts configured.

It takes some finding though...

Open the dialler, Settings (...), Calls, Calling accounts, Internet calling (SIP) accounts.

Here you can opt to have it log in continually and be a true two way (inbound and outbound), which can be a bit heavy on the battery, or just outbound, which will allow you to at least call someone back from your SIP number and appear to be in the office.

You'll want to set the "call with" option in calling accounts to "ask first" to do this.

As for call quality, I'm not sure why the OP says it's substandard... Maybe in the early years it was, but I've been using SIP as a primary business provider for years, and the only issues experienced have been from a LAN switch fault. The more modern codecs far exceed the audio bandwidth of the traditional phone network, so a SIP to SIP where all parties support that codec is going to sound far better.

[Anonymous Coward]

Re: No SIP app required on modern Android hand sets

"As for call quality, I'm not sure why the OP says it's substandard"

It's substandard compared to more modern Codecs like RTAudio and SILK which are being widely deployed these days...

[Paul Shirley]

Re: No SIP app required on modern Android hand sets

Unfortunately the native SIP support seems to be optional, it came and went at random as I replaced firmware. I don't remember it ever working with my sip provider on my last phone in any case and I can't find any sign of it on my LG G2.

Luckily CSipSimple has worked reliably and integrates with the normal dialer.

[Steve Evans]

Re: No SIP app required on modern Android hand sets

Which is why I specified the "standard" google dialler. OEMs have a terrible habit of leaving bits out with their (usually pointless) reskin. I've been a Nexus boy since HTC stuffed me and left me on gingerbread. Never regretted it.

It's the same with the camera apps, very few of them add anything over the standard Android one these days, but quite often skip a few things.

[Anonymous Coward]

Really?

"Even in 2015 you seldom see an organisation that uses just IP trunks to call external numbers"

1.5 million calls a month by us may disagree. ISDN free for 3 years and we, by no means, are a big business.

[Anonymous Coward]

Re: Really?

Yeah, we've been IP only for several years - not as many calls though. As for 'international being for home users' - we have people in Germany connecting to our UK system and back out for their local calls. It works fine, if you pick a decent provider.

[Dazed and Confused]

Re: Really?

SIP over the Internet seem to normally give very good quality.

I'm using A&A as both my ISP and SIP provider. I can't say I've never had problems, but normally the quality is very good. I've had lectures I give recorded and the sound engineers have always commented on how good the quality is.

I have a VoIP gateway to POTS as a backup but the quality of that isn't so good. I hear a 50Hz mains hum on my end but the customers say it sounds fine at their end.

[Anonymous Coward]

What the fuck?

"These can cost next to nothing, particularly if you are in a big city, and you can use them either as an IP link or a telco-standard DASS II connection."

DASS 2...standard....is that like ie6 is web standard compliant?

FFS get something right.

DASS (2) is a OBSOLETE BT PROPRIETY "standard".

[Anonymous Coward]

Re: What the fuck?

"DASS (2) is a OBSOLETE BT PROPRIETY "standard"."

I still run into it from time to time so I think that makes it obsolescent, not obsolete. Any modern kit will tend to use QSIG by default for a TDM connection - though they're getting to be quite rare - the fall in the cost of bandwidth means that people aren't so cost sensitive to G.711 on VoIP costing more than G.711 on TDM (100Kbps versus 64).

[A Non e-mouse]

Re: What the fuck?

And you wouldn't order a DASS-2 connection from a Telco. You'd order a 2Mb/s circuit and slap DASS-2 interfaces into your PABX. But as Lost all faith says, DASS-2 is obsolete: You'd go Q.931 nowadays instead.

(Of course, if you're ordering a 2Mb/s connection from a Telco, why not just run IP over it?)

[Blacklight]

It's fun....

I saw SIP in use originally in a commercial arena, and wanted to play - so setup Asterisk, with an SPA3102 linked to my DECT handsets. VoIP + PSTN failback, all worked nicely - until you realise the some PSTN carriers don't play nicely (Virgin + Clear on Disconnect? Not without lots of emails).

I've used 'free' systems like Voxalot, and commercials (like SipGate, VoIP.co.uk etc) and never had bad quality on any. The hardest bit is generally sorting out why Asterisk will play nicely with Trunk Provider 1, and not Trunk Provider 2....typically down to some esoteric setting.

But it's nice wangling cheaper/lower cost calls. If Google Voice hurried up and came to the UK properly I'd be plugging that in too....

[Minimaul]

Crap article

This article is pretty bloody awful... I can think of so many holes it's not even funny.

"Even in 2015 you seldom see an organisation that uses just IP trunks to call external numbers. ISDN lines are still the primary way to connect to the world, for the simple reason that they work and you can be absolutely sure – unless there is some kind of hideous hardware problem on the network – that the signal will get from end to end intact." - this is crap. A *lot* of businesses use SIP exclusively now. We do.

"Most SIP (Session Initiation Protocol) services rely on people connecting to them over the internet, which means performance can be variable. If you are calling in your own country, however, it is often acceptable unless you are, say, a call centre that really cares about sound quality." - so get a decent provider and a decent internet connection. It just works *fine* then.

"Can I use SIP for cheap international calls?" Yes, you can. Just fine, and with superb quality too.

"Moving to SIP for international calls is for home users with relatives overseas; it is not for businesses." Yes, it really is for businesses, you won't tell the difference vs ISDN, and it can save a fortune. Again, don't go with the absolute cheapest provider, but find a decent one you can trust. There are a lot of these about in the UK.

"If your phones can only do 100Mbps Ethernet and your users whinge that this isn't fast enough, tell them to get lost. Generally it is fine unless they are doing stuff like throwing high-res graphics and video around." When was the last time you worked on an actual network? Even Sage wants gig-e to perform sensibly on accounts of any size. Loading decent sized office documents and PDFs is an issue on 100mbit even!

[A Non e-mouse]

Re: Crap article

It's not just this article that's crap: This whole series of articles on VoIP is dire. They're almost written by a marketing droid who's just throwing around some buzz-words.

Sorry Dave Cartwright, I just don't think these articles cut the mustard.

[joewilliamsebs]

Re: Crap article

Fully agree. It may be "VoIP for non-techies", but the advice is so out of date. I dread talking to a business owner who's read this article.

We haven't installed a new ISDN line for 6 years, and that was only because the customer had been tricked into a long-term BT contract and couldn't cancel.

[BillDarblay]

VOIP

is the infrastructure career graveyard.

[Anonymous Coward]

Re: VOIP

OK we get it, you're bitter and twisted and you gave up on SIP years ago before it came of age. Get over it.

[Anonymous Coward]

Re: VOIP

"VOIP

is the infrastructure career graveyard."

Unless you are involved with Lync. The growth rate / demand is amazing.

[I ain't Spartacus]

Moving to SIP for international calls is for home users with relatives overseas; it is not for businesses.

I disagree. The call centres for my business selling anti-virus software, because Microsoft have reported that your PC has been infected, find it perfectly acceptable...

[Anonymous Coward]

Handsets?

You lost me at handsets. They are rarely justified, very expensive and basically just a small but mostly useless PC taking up an Ethernet connection. They also lock users to a physical location (please don't tell me about extension mobility).

[Anonymous Coward]

Re: Handsets?

but don't suffer issues when the pc gets battered by an update, someone loading a page with a crap load of flash and Java or decides to randomly blue screen.

PS not me down voting. Each has it's place, but to blanket rule out handsets is like saying everyone should have one.

[Paul Hayes 1]

What a terrible article. Has the writer had any experience of telecoms since 1987? You don't use DASSII for anything any more, it's a pretty rare to find it still in use anywhere. Even q931 is ancient technology.

This whole article reads like a review of "VoIP" from 2005, not 2015. Things have moved on.

[Mango]

> The only time you want to care about QoS is if you are doing IP Voice over a WAN of some sort

That's *almost* like saying "the only time you want to care about using an umbrella is if it's raining".

In other words, a huge proportion of users route VoIP calls over the internet (which is a WAN), with results indistinguishable from a POTS line. How? With QoS. Due to the real-time nature of VoIP, it's absolutely essential to give VoIP traffic priority over normal internet traffic. Unless you're paying for massive amounts of bandwidth you're not using, you simply CANNOT overlook this.

> A word of warning: if you want the provider to give you QoS over the WAN there is probably a fee.

I'm not sure about other parts of the world, but no ISP in Canada that I've used offers this. Fortunately you don't need it. A good, properly-configured router will will manipulate requests and receipts to effectively throttle *both incoming and outgoing* nonessential internet traffic. Any other way, VoIP over the internet wouldn't work.

[Lee D]

Not all VOIP is exteranl.

I work in a school.

We put in a phone point in every classroom and every office. You have to be able to send calls to the teacher, the teachers need to call in assistance (in rough schools), emergency numbers, the office to check on children, the parents to see where the kids are, etc.

We have 4 outgoing ISDN lines. Everything else is internal, there is no SIP to the outside world so there's no IP traffic outside the local network (though when my leased line comes through, it's the first upgrade planned).

We also have gigabit-to-the-desktop.

Hint: Guess what was the first option we had to turn on once we had a normal amount of traffic on the network and 30+ phones? QoS. Because, although the outside lines were fine, after a certain number of handsets, and with day-to-day server replication etc. we were experiencing phone calls dropping because the network couldn't keep up. Even VLANning the phones off didn't help much because they still shared the same priority as someone downloading their roaming profile.

You HAVE to put QoS on after a while. And it cures the problem instantly. Haven't had a problem since and the effect was immediate (VLANning it off helped in that we QoS'd the entire voice VLAN rather than the individual phones, protocols, etc.). If I have to put QoS on in a small school with only 50 internal phones and all analogue outside lines, it's not something that you "only want to care about" in an extreme scenario. And I guarantee you that when we get our SIP outgoing, we're going to need to QoS them against the kids downloading huge videos even if that's only on our end.

QoS exists in every managed switch (and has done for, what, 10-15 years?), and is a commodity feature, because it's necessary. Not if you have two phones on an idle gigabit network, but any serious scenario of IP phone deployment requires it. Hell, we can do several gigabytes of voice data a day just on internal calls.

[Chris Evans]

Call centres.

"a call centre that really cares about sound quality." does one exist?

As a punter EVERY call centre I've ever had the missfortune to use has been bad.

[Lee D]

Re: Call centres.

Once had one calling to sell me telephony services (specifically VoIP).

Line was so bad, I made them call my mobile.

Line was still bad, made them call the workplace landline direct.

Line was still bad, told them I'd never touch their products if they can't make a coherent phone call themselves in order to sell it.