Cheap Telephone Calls 2015

This article covers what I have changed over the last couple of years with regard to telecoms costs.

Internet Access

In my previous cheap telephone calls article I used an app on my iPhone to route calls over Sipgate (UK)/Localphone/netSIP.

At the time I had O2 Broadband at home, and was spending £6.00 per month on O2 pay-as-you-go (PAYG, pre-pay) for an All Rounder data Bolt On that gave me a 20 MMS allowance (never used) and 500 MB data.

At the beginning things were good. My landline was with the Post Office (Home Phone) as it was the cheapest way to get a new BT line installed and only required 30 days notice, and as long as I topped up my mobile phone with £10.00 every 3 months £5.00 was knocked off my O2 broadband bill every month.

At the start my home broadband was £7.50 per month after the mobile discount was applied. That then crept up to £9.50 per month. Then Sky bought out the O2 home broadband division and after a problematic migration I was paying slightly less (£9.00) for 12 months after which point I would have been paying £14.50 per month.

At some point Sky decided they would be increasing the price after those 12 months even higher and at the same time something started to look wrong with the Post Office.

Rip-Off Line Rental and Broadband

I had paid £120.00 for 12 months Post Office Home Phone line rental up front using their line rental saver. Despite the cost of a line from BT Wholesale going down, Post Office decided to raise Line Rental Saver to 144.00 per year "to be more competitive" with those other companies, like Sky, that were raising their prices.

As the terms were unfavourable (a 20% price hike) and my Sky broadband was simply a rolling (month to month) contract and it hadn't doubled in cost to £15.00/month yet, I could get away from both services within 14 days… so I did.

After O2 sold to Sky, I no longer had to top up my phone every 3 months. It took over a year to whittle away my O2 mobile balance from nearing £100 down to £0, as the only thing I was spending my balance on were those data bolt ons.

I had spent over a year using BT's Infinity Broadband checker and it looked like my home was never going to be connected to an upgraded street cabinet. Slower-than-superfast broadband speeds had been annoying me for a while, and with all providers hiking prices just to increase profits (or possibly because they offer TV packages I, a non-TV-owner, would never want) I decided it was time to look for a consumer broadband package I could live with.

Upload speeds are becoming more and more important. In fact one of the things I hated with Sky was that my upload throughput went from 1.3 Mb/s to 0.98 Mb/s after taking over from O2—so a 157% price increase for a 25% slower upload speed.

When comparing with Virgin Media Broadband, I noticed a big difference between Sky and Virgin. Whereas Sky were charging more for giving me less service, Virgin have been ramping up their prices whilst incrimentally increasing speeds. Thus, I started looking at Virgin's Fair Use Policy (FUP).

Virgin have recently changed their FUP so that speed limiting is based on uploads rather than downloads. I decided to go with the 152 Mb/s (download) package because of the upload speed (12 Mb/s) and the upload thresholds looking manageable—basically I just wanted fast even during times I am bandwidth limited (streaming at 1080p to somewhere like Twitch would have me hitting the upload cap after 1-2 hours, and if I recall my maths I could stream 720p indefinitely).

Just now, at 16:39 BST (UTC+1) on a Saturday, I got 94.90 Mb/s download throughput and 12.26 Mb/s upload throughput. Watford are playing at home, Formula 1 is on BBC1 followed by the FA Cup semi-final with Arsenal kicking off at 17:20 BST, and a new version of iOS has been released. I don't know when things are typically congested on my cable node (or whatever the terminology is), but 04:00 UTC+0 is generally when the Net is quiet, not when it is an early Saturday evening in Britain.

Having retested speeds at 05:00 BST on a Tuesday, it looks like it is a LAN throughput issue as the speeds are consistent—running a speedtest using Putty, Xming, and google-chrome, I got a result of 155+ Mb/s down and 12.2 Mb/s up.

To get a 76 Mb/s download and 19 Mb/s upload with BT Infinity, I would be looking at £26.00/month for BT Infinity 2 Unlimited, and £16.99/month line rental (or £169.90/year up front) coming to £40.158333/month which is just slightly less than the £41.00/month I am paying Virgin. Oh, and I forgot to mention: BT Infinity is still not available where I live.

So that is why I opted for Virgin for my home broadband. Although there is a greater chance of "no Internet" if the street cabinet or somewhere else on Virgin's network has a power failure compared to with ADSL2+, I don't need a 100% SLA as an hour or two broadband outage will be annoying rather than interrupting anything critical.

I also have my Fon 2.0n hooked up for my Wi-Fi (my Virgin Super Hub is running in modem mode so my home server has a public IP address) so if the Internet were to go down I could hop on to a nearby BT Fon hotspot until it came back up.

SIP Providers

Sipgate UK have recently relaunched their residential service. Localphone are still competitive on prices. I had a bit of trouble with my netSIP account due to inactivity, but after eventually getting through to them and getting things resolved I decided to ensure I make at least one chargeable call per month through them—I just call BT's News Service once a month using netSIP, with my call on 20th March costing me 1.47 pence (4 minutes, 44 seconds duration).

Calls To Localphone Sipgate netSIP BT Virgin
UK 01/02/03 0.5 p/min 1.19 p/min 0.490 p/min 15.97 p + 9.58 p/min 17.5 p + 10.6 p/min
UK Mobiles (major networks) 1.8 p/min 9.9 p/min 1.470 p/min 15.97 p + 12.77 p/min 17.5 p + 19.35 p/min
UK 0870 4.8 p/min 7.51 p/min 1.372 p/min 15.97 p + 9.58 p/min 11.24 p + 10.22 p/min
UK 0845 9.84 p/min 3.00 p/min 14.014 p/min 15.97 p + 2.042 p/min 11.24 p + 10.22 p/min
UK Freephone (0800/0808/0500) 0.00 p/min 0.00 p/min 0.294 p/min 0.00 p/min 0.00 p/min
UK Personal (070) Varies 30.576 p/min Varies Varies
International Numbers (+883 5100)/iNum 0.00 p/min 15.97 p + 60.00 p/min

As can probably be seen from the above table, VOIP prices are generally much better than those that BT and Virgin charge. Yes, I have listed the peak daytime prices for BT and Virgin and ignored calling plans because I wanted a rather simple table.

I could have thrown override providers in as well, such as 18185 which charge 5p per call to UK Landlines, but that would also have complicated things as they have override and access number rates as well as different rates for weekdays and weekends.

When it comes to call costs, I prefer things when they are simple. It is for that reason I have noted a call rate of Varies for Personal Numbers (070) where the rates vary depending on subsequent phone number digits. My call to NHS 111 using their alternative number, for example, lasted 12 minutes and 6 seconds and Localphone charged me 6.24 pence for the call—had I called from a normal landline or mobile that call would have been free.

A couple of days ago I got home from hospital and needed to arrange for my wound to be dressed daily. Between my GP and the hospital I made 5 calls totalling 13 minutes 3 seconds and costing 7.2 pence. Obviously they were what the incumbants would call peak weekday calls. On a BT landline that would have cost me 79.85 p + 9.58(3+9+1+1+2) = 79.85 + 9.58(16) = 233.13 pence, or more than 31 times more than what I paid.

Mobile Phone

As I no longer had any reason to be with O2, I started looking around. Andrews & Arnold SIP2SIM service looked like something I could utilise, although costs needed a bit of calculating to work out if it would be suitable.

Three's 321 SIM also looked good, especially for 1p/MB of data and 2p per SMS.

Although Three doesn't block VOIP/SIP, incoming calls on my iPhone using Groundwire had become an annoyance because I'd tap the push notification and then I had to wait for the app to start to be able to answer a call. Even then I had occasional problems with one-way audio.

Although Android has a built-in SIP client, from what I could find out it looked like it would use a lot of battery.

After looking at Android phones, I asked myself a simple question: am I usually making calls when I am at home? The answer, surprisingly, was yes. As had been typical when I was out and about, I had tended to also make calls when connected to Wi-Fi using Groundwire.

The question about receiving calls was a bit harder to answer. When I am in a fitness state of mind I can spend 6 hours a day walking, whereas when I am sedentary I might only walk 10 minutes a week. Longer calls, however, were generally conducted when I was at home.

Based on these observations, I decided that instead of buying an Android phone I would repurpose my iPhone. I would use SIP2SIM for incoming/outgoing calls when not on Wi-Fi, and Groundwire (or the Sipgate app if experiencing one-way audio) for outgoing calls when on Wi-Fi outside the home. At home I would use a Digium D70 SIP phone for making/receiving calls—all my telecommunications would become reliant on my home server and my home broadband connection.

As text messages on SIP2SIM are more expensive than those on Three (2.4 versus 2 pence) and I had decided to keep my iPhone rather than get a dual SIM Android, I ported my O2 number to a Three 321 SIM and unlocked my E220 dongle. With my 321 SIM in my E220 dongle, hooked up to my home server, I set to work incorporating SMS with Asterisk.

It took some work, and it is still not perfect, but now I use Groundwire to send/receive SMS messages via my home server and all incoming messages are also dumped into a MySQL database. This meant I would not have to pay A&A for incoming SMS's.

This incorporation also had a side-effect: I can now use cron jobs to send myself "text" reminders from my home server to my iPhone using SIP SIMPLE messaging (with push notifications) and instead of costing me 2.4 pence to receive each message (or 2 pence to send it via the dongle) it only costs a little bit of data.

Another great thing about SIP2SIM is that usage is based on usage. By that I mean if you answer a call that only lasts 5 seconds, you get billed 2.4×560 = 0.2 pence. Likewise data usage is billed per kilobyte rather than per megabyte.

On O2 I was using the All Rounder Bolt On because the cheaper Basics Bolt On only came with 100 MB/month data usage and, depending on how active I was, I was typically using between 150-350 MB/month. With SIP2SIM costing £2.40 per month, I would have been paying more on SIP2SIM than O2 if I were to use more than 150 MB of data per month.

That, however, hasn't been the case. Admittedly I have been sedentary for the entire time of having SIP2SIM, but after the initial outlay of £6.00 for the SIM my monthly SIP2SIM invoices have been £2.26 (first month), £4.61, £3.49, £2.76, and £2.94. Including the cost of the SIM that is an average of £4.412 per month, which is cheaper than the £6.00 per month for the All Rounder.

I should also mention that after switching to SIP2SIM I modified my iPhone 3G (data) settings so that things that use a lot of data unnecessarily are not permitted to use mobile data. I have also deleted all my e-mail accounts until I have finalised my home e-mail server set-up and decided whether I will be relying on using a VPN to my home network or to open up my firewall and make IMAP publicly accessible.

For the time being I don't have Notes enabled on my iPhone nor do I have iMessage enabled as I couldn't get the authentication text messages to send/receive correctly.

I have also set up a monthly usage warning at £5.00 and a usage limit of £10.00. That means if my call and data charges exceeds £5.00 in a billing period I receive an e-mail alert and if it hits £10.00 Andrews & Arnold will try to stop further usage.

Assuming the limits are excluding VAT, that means if I were to use 500 MB of data in a month I should be prevented from using more. With me relying on Wi-Fi more than 3G, the odds of me hitting my self-imposed usage limit are slim. In fact, £10.00 usage in a month is more likely to be caused by a phone/app bug or a security compromise than me, making it a suitable ceiling height.

As for costs, I would have spent £30.00 in the last 5 months had I stuck with O2, and instead have spent £19.80 on SIP2SIM. With my D70 having a cost of £195.42 and my POE switch costing £95.99, I have spent £291.41 on my home phone system. Deducting the savings made from switching to SIP2SIM, that cost falls to £281.21.

If I were to focus purely on the maths it would take 8–15 years to break even. Instead I am looking at the cost of the phone I almost bought. The LG G3 with 32 GB storage and 3 GB RAM is currently going for £287.99 on eBay UK.

I bought my 64 GB iPhone 4S for £699.00 32 months ago hoping for a 3 year life—i.e. an average cost of £20/month over 3 years rather than O2's £30/month (plus interest) over 2 years. A bit like me justifying the cost of my Alienware m17x R3 if it lasts me 5 years (45 months down, 15 months to go).

I recently replaced by m17x's broken keyboard and battery, and I previously upgraded the RAM and HDDs, so I really need it to last for a total of 75 months (i.e. until October 2017) although I bought the RAM 18 months ago and it is still £40.00 more expensive than when I bought it so it is retaining its value, although one stick may have become faulty (need to test).

Likewise I recently (14 months ago) replaced the case for my iPhone 4S because the screen protector became too scratched, but that was a planned expense at the approximate 18 month mark.

Anyway, with 4 months of "hopeful life" left in my iPhone 4S, I have probably bought a further year before I need a new phone. 5 Ghz Wi-Fi (including 802.11ac wave 2) and 4G are things that would be worth upgrading my phone for if I would actually utilise them.

As things currently stand, 802.11n on 2.4 Ghz is sufficient for my iPhone use at home, as is 3G when I'm out and about. Mobile data is still way too expensive for what you get—for £41.00 per month I can download up to 49 TB per month at home. If I were to call that £1.00 per TB, Three's 321 plan is 10,000 times the cost of my home broadband. Before switching to SIP2SIM I made a lot of tweaks to my phone so that, for example, the app store is forbidden from using 3G data.

Mobile Costs

By combining AAISP's costs with the current best rate out of my 3 SIP trunk providers and my 321 SIM, the costs for my total telecoms system is as follows:

Description AAISP SIP2SIM Localphone Sipgate netSIP Three 321 Total
Line Rental £2.40 £2.40
Calls to 01/02/03* 2.4 p/min 0.49 p/min 2.89 p/min
Calls to UK Mobiles (major networks) 2.4 p/min 1.47 p/min 3.87 p/min
Calls to UK 0870 2.4 p/min 1.372 p/min 3.772 p/min
Calls to UK 0845 2.4 p/min 3 p/min 5.4 p/min
Calls to UK freephone 2.4 p/min 0 p/min 2.4 p/min
Inbound Calls 2.4 p/min 2.4 p/min
Outbound SMS 2 p 2 p
Inbound SMS 0 p 0 p
Data 2.4 p/MB 2.4 p/MB

* Calls to Police 101 and NHS 111 are routed using geographical numbers.

Thus, I can now compare what I am paying to what I would be paying on PAYG on the other mobile networks.

Description John Cook UK Three 321 O2 EE Vodafone Giffgaff
Line Rental £2.40 £0.00 £0.00 £0.00 £0.00 £0.00
Calls to 01/02/03 2.89 p/min 3 p/min 35 p/min 30 p/min 30 p/min 10 p/min
Calls to UK Mobiles (major networks) 3.87 p/min 3 p/min 35 p/min 30 p/min 30 p/min 10 p/min
Calls to UK 0870 3.772 p/min 35 p/min 20 p/min 40 p/min 14 p/min 12 p/min
Calls to UK 0845 5.4 p/min 35 p/min 20 p/min 40 p/min 14 p/min 12 p/min
Calls to UK freephone 2.4 p/min 15 p/min 20 p/min 20 p/min 14 p/min 0 p/min
Calls to Police 101 2.89 p/min 15 p/call
Calls to NHS 111 2.89 p/min 0 p/min 0 p/min
Inbound Calls 2.4 p/min 0 p/min 0 p/min 0 p/min 0 p/min 0 p/min
Outbound SMS 2 p 2 p 12 p 12 p 14 p 6 p
Inbound SMS 0 p 0 p 0 p 0 p 0 p 0 p
Data 2.4 p/MB 1 p/MB £1 for 50 MB/day £1 for 100 MB/7 days £2 for 50 MB/day, then 10p/MB 20p for 20 MB/day, then 20p/MB

There is, of course, a cause for confusion at the moment because I have two UK telephone numbers: one for telephone calls, and one for text messages. Just today I found out that the nurse at my GP surgery attempted calling my mobile (SMS only) phone number.

It is therefore also an issue when my home broadband goes down. No Net, no SIP trunks, no phone calls.

One possible solution would be to upgrade my E220 to a USB dongle that supports voice calls. By bridging calls to my mobile number over SIP I will be able to receive calls on that number again, as well as make/receive calls on my D70 when my home broadband goes down.

The problem with that, however, is that chan_dongle does not yet support Asterisk 13 LTS and I'm not sure if disabling SMS support in chan_dongle would allow me to continue to use gammu-smsd—I don't want to change my current SMS system.

Another alternative would be to put my 321 SIM in a GSM gateway. Those are not exactly cheap though and I am not sure if something like the GoIP would be able to do what I want for text messages (i.e. Asterisk forwarding them over SIP SIMPLE).

High Maintenance and Downtime

My current system is what could be called "high manintenance".

Whilst writing this article I double-checked the current prices whilst creating the tables comparing my SIP trunk providers. Because SIP provider call prices are not static my Asterisk dialling/routing rules do need tweaking every so often so that "least cost routing" is actually occurring.

I also need to ensure my home server is not having problems, although the odds of me losing Internet access and not noticing before my D70 starts lighting the BLF lamps amber indicating that some/all of my extensions have lost connectivity to Asterisk is also slim (unless I am asleep that is).

Only the other day my home server lost Internet connectivity. After 10 minutes I logged in directly and issued sudo ifdown eth0 and sudo ifup eth0 to no avail even after turning my cable modem off and on—it looked like Virgin had an issue and their DHCP server wasn't responding.

When I update my home server and a new kernel or an important security patch is applied, I reboot to ensure that the new code is being run. Although that is an occasional (Heartbleed; new kernel) issue, it does still result in a few minutes of downtime.

As a home user, as long as my phone system is working when I need it to (outgoing calls, waiting for an expected incoming call) then it is less of an issue to me than if I were a business. If I'm rebooting my server someone can just redial a few minutes later. If I power down my server or experience an outage I am likely to report it on twitter.

As my mental health issues cause long periods of time where I am unreachable by phone (and often all methods of communication) a phone outage is even less of an issue than for a mentally well home user.

As I have 3 different SIP trunk providers, as long as my Internet is working and my firewall and DNS are functioning properly, and my Asterisk server is running normally, I will still be able to make outgoing calls using my D70 by selecting a specific outgoing trunk line instead of a generic (least cost routing) line to make a call.


At present I am reachable over pure SIP via my Localphone iNum numbers with appended.

ENUM for is run by Nominet. At the time of writing ENUM takeup in the UK is extremely low because none of the ENUM registrars for +44 numbers are offering End User ENUM to consumers.

The two Nominet pages for ENUM that would be useful (list of registrars; list of authenticators) return page not found errors. The Nominet documentation about applying to become an ENUM registrar is still, over 6 years later, so sparse an e-mail address is provided for further information.

The UK ENUM Consortium Limited (company number 05959274) is, according to Companies House, dissolved. They are supposed to be the ones determining whether Nominet's contract for running should be renewed. The ITU list the delegee as "DTI/Nominum"—Nomium's site search tool has zero results for 'enum' and 'e164', and the latest Google has from the DTI is about a consultation from 2004.

The way the UK ENUM appears to have been decided to be run, is an end user goes to an ENUM Registrar with their details and phone number, the ENUM Registrar verifies ownership of that phone number using an Authentication Agency, and the queried Authentication Agency queries identification and validation sources to confirm the ENUM Subscriber (registrant) owns that telephone number.

The problem with this system is that it is so convoluted and burdonsome that there are a total of zero ENUM Registrars in the UK offering a consumer service nearing seven years after launch. If uptake of .uk SLDs were this low Nominet would have scrapped the idea rather than launch it. To quote a slide from the DTI: "Trial 2003 - established that framework is OK but little trial traffic".

Since then we have had a recession, an economic slowdown, and are on the cusp of possible deflation. Admittedly, free phone calls throughout the UK routed over Wi-Fi would increase the deflationary pressure, but the incumbent telecommunication companies are raising call prices and line rental despite the wholesale cost going down. Why do all the companies think we all want bundled landline, broadband, TV, and mobile, if it means we end up paying more?

As for mobile data, there is something I should probably cover: Wi-Fi. With Virgin Media I have access to the Wi-Fi on the Underground. With my Fon 2.0n router I have access to the BT Fon network. With the O2 Wifi app I can use O2 hotspots.

Subscriber control and authentication

  • Identification - who the subscriber is
  • Validation - right to use the E.164 number
  • Telcos can identify and validate, but may not want to
  • Various alternative methods of checking bills, directory enquiry, using number portability process (not database), calling back
  • Area most likely to change as a result of responses to Consultation

This is what the DTI presented on one of the slides, and is pertinent to the obvious hurdle I would face were I to ask Nominet about becoming an ENUM Registrar - I would have to become an Authentication Agency as well because there do not appear to be any open available to the general public.

As I currently only hold a Self-Managed TAG, the likelihood of me being able to become an Authentication Agency are slim. While I could validate phone number ownership by calling or texting a phone number and asking for a code, I'm not quite sure whether Nominet would trust an individual to do things properly.