TelNG is a UK telecoms provider. We originally interconnected with BT when they first launched their IP Exchange product in 2007. All went well until recently; we spent the best part of £5,000,000 with them in that time, and we were (mostly) happy customers.

Then we had a dispute over whether some traffic is artificially inflated and, as a result, BT decided to terminate our IP Exchange contract - basically, they're not paying our bill and cutting us off. The standard IP Exchange contract allows them to do this on 30 days' notice for any reason. We received a termination notice on March 2nd, which BT extended a couple of times and then withdrew. We had discussions with Ofcom during this time, and referred a dispute to them asking them to make a determination that the clause allowing BT to terminate "at will" was undesirable; Ofcom declined to investigate. BT subsequently re-issued the termination notice.

The old-fashioned TDM interconnect under the Standard Interconnect Agreement does not allow BT to terminate "at will" - well, they can, but they have to give 24 months' notice and renegotiate a new agreement. It also provides signatories with a seat at the SIA working group, which makes various determinations as to how interconnects are managed. As a case in point, it's responsible for working on the AIT provisions; these are then imposed on IP Exchange customers without their having an opportunity to have their voices heard.

I therefore decided that we should interconnect with BT under the SIA. After a brief look to see if I could find a mostly-defunct organisation to acquire (which failed), we started the process ourselves from scratch. I thought I'd write a journal, both for my own amusement and because it's not impossible that we'll be the last people to do this..


Looked up the literature on the TDM interconnect on BT's website. Apparently it's a low-cost solution, offering excellent value and enormous flexibility. E-mail asking to initiate the process to interconnect under the SIA as directed.


E-mail again asking to initiate the process to interconnect under the SIA. Place a call to their advertised number, which doesn't get answered by a person in the space of the 20 minutes I'm on hold. Call my account manager, who doesn't know much about the process, but will find someone and get back to me.



Raised the radio silence with TM. I'm told that I should follow the industry-agreed process. I ask where I can find details of this process, send reminders on 17/5 and 21/5, and hear nothing back.


Next try. Have an educated guess and send a further e-mail to another e-mail address within BT. It's for anyone foolish enough to also be travelling this road.


Result! I have reached the correct folk. They've asked for some documents, including a "statement of requirements." I ask what that should include - "we'd like to interconnect under the SIA" appearing to be where we're at - and I'm asked to provide as much information as possible.


Statement of requirements, company info, etc. provided.




Received a confidentiality agreement and a few other documents.


Documents returned.


Chased for an update; the documents had been stripped off by BT's mail system. Resent (per request) as a password-protected ZIP file. This is utter madness from BT: a password-protected ZIP file's the last thing you want being sent through your e-mail system, as there's no way to scan what's in there. Fortunately, I'm a good chap, and didn't use this opportunity to attempt to infiltrate malware into BT's network.


Signed copy of confidentiality agreement received.


First call with TAM. Agreed next steps:

We're the first folk in some 18 months to start down this road.


Start looking at BT's approved (or, at least, already-tested) switch list - if a switch is on there, the testing requirements are reduced. Have a look at options, and the Sangoma Netborder SS7 looks like a good one. Call Sangoma, and get put in touch with one of their resellers.

E-mail sent to ask to be included on the mailings for changes to the Carrier Price List.


Proper look at BT's SSQ. Lots of stuff I don't know, such as:

Ask Sangoma for help.


Some stuff back from Sangoma, but not much. Dig some timer values off their website, and others from the relevant standards.

The SSQ is a pig's ear - it's suffered from bitrot (presumably from being moved around), gives a bunch of messages about not being able to find things, and the second page is almost entirely unformatted. Fill it in, press the button to send it off, sigh of relief. I suppose something which is hardly ever used doesn't warrant maintenance..


The "How far am I from a switch" tool is for BT's internal use only. I'm told that I should be able to download a list of BT's switch locations from the website. Look, but can't find this particular needle in what's a very large haystack.


E-mail a (relatively) short-list of colo sites to our TAM.


"I've been informed this would be consultancy type work and for the CP [that's me] to do, so I'm afraid I need to tell you have to do the planning work yourself."


TAM tells me that the files I need are in the NIPP section on BT's website - why not tell me this two weeks ago? - to which I don't have access. Request access via the 'My apps' section as instructed, and get an e-mail confirming that the request will be read within 24 hours.


Bored of not being able to progress owing to (deliberate?) sluggishness on BT's part. E-mail to TM and CS, copied to Ofcom.

E-mail sent (again) to ask to be included on the mailings for changes to the Carrier Price List.


Aha! Have access to the planning files I've been needing. And the chap who does pricing has got back to me, asking me to e-mail the address I've already e-mailed twice to get on the mailing list for the price list.

On the downside, one question on the SSQ wasn't answered and so I've been asked to update it - which means fill in the entire sodding thing again from scratch.


Having now got access to the NIPP data, I could start to build a copy of the tool which BT have (but would not share) which gives radial distances from postcodes to the nearest NGS switch. The files required are

The postcode data's split up into a bunch of files, one for each alpha prefix. Reading the whole lot takes a few seconds and, as that's good enough for this application, I've not done anything more intelligent than slurp it all in each time there's a query. Should anyone ever need this, e-mail me for access.

2018-08-02 - Happy Birthday (to me, not this process)

Selected three candidate DCs, of which City Lifeline looks like a good bet - 4 NGS switches within 4 km, and BT certainly used to have a presence there. Also one in Reading and one in Birmingham - the latter's attractive as there's 3 NGSes within 2 km and it's a short drive from Leamington.


Hear back from a bloke at Sangoma who I originally attempted to contact a month ago.. Pricing for City Lifeline received. SSQ resubmitted, and enquiries set out to a clutch of other data centres.


Planning day. Fall at an early hurdle: the capacity profile spreadsheet (which says how much capacity we'll be ordering on a monthly basis) is password-protected. Ask our TAM for the password - get it within 10 minutes :-) If only filling out the spreadsheet were so straightforward..

It also turns out that we have to interconnect at an NGS(J) - equivalent of a DJSU - if we want our London ranges to work. So I wrote a little thing which displays NGS and NGS(J) locations on a map. Again, e-mail me for access.


We need a "1141" code for each of our proposed switches to progress with the capacity profile. To get one of these, we need a point code for the switch. Fortunately, we already have one (12666 - make up your own Revelations-based reference), but that's assigned to a different address. Ofcom's number management system wasn't keen on updating the address or switch details, but was cajoled into doing so eventually. Also applied for another point code, which appears to be on a 3-week lead time..

Application for 1141 code for our first switch in. We might start with just the one, depending on how much waiting for the second point code would delay us.


Ask how long the 1141 code will take. "Should be allocated next week." Stalled again.


Submit a revised SSQ - might as well get on with something. Ask for more pricing options for the Sangoma Netborder SS7 - turns out that one licensed for four ports with two extra port licenses is less expensive than a six-port one.


According to TM, the reason why we've not had our 1141 code for the switch is because our SSQ's not approved, and this is part of the process. It might be part of the process, but it's not documented anywhere - indeed, the capacity form requires a 1141 code and notes that an SSQ should be submitted with it if one's not already been provided. At least one of whoever prepared it and TM are wrong.

This is becoming a bit tedious. BT keep on dragging their feet, not supplying information, and inventing bits of undocumented process to excuse their inability or unwillingness to make progress on this project at a sensible rate.


Answer a question relating to circular routing of MTP messages, which appears to have expanded to include circular routing of calls. Slightly puzzled, as this is a non-issue according to the UK interconnect specs.


Chase the 1141 code. Get a request for a copy of the Ofcom certificate for our point code - why wasn't this in last week's request for info?

Sangoma box ordered - shhould be here on Monday.


Forward a snapshot of the Ofcom NMS page for our point code. Update request for new point code with information requested by Ofcom.


Got the 1141 code!


Ofcom allocated our point codes, and the capacity order/traffic forecast is in. Now, I think, is where the serious waiting begins.


..and doesn't it just. I was asked today for our VAT number (which BT Wholesale has had for the last decade) so that they can perform a credit vet, which they've done several times in the last decade. Sent an e-mail requesting a call to discuss progress.


Home-grown SS7 stack answered its first call :-)


Called TAM; no reply. Slightly stiff letter to our commercial contact and TM regarding the lack of progress.


Spoke to my TAM, who's just back from holiday. Not quite sure why someone else wasn't handed reponsibility in his absence. Promised an update on the outstanding issues tomorrow. Quick note to the "commercial interface" folk about setting up a Customer Service Plan, a joint obligation which we've missed so far.