BT SIN 498 - MCT Approval for VDSL2


What is BT SIN 498 MCT Approval?

Executive Summary : From March 2016, all VDSL equipment must have passed BT's SIN498 MCT testing in order to be connected to any VDSL line provided by BT Openreach (regardless of your ISP).  The purpose of approval is to have a consistent network experience/performance by ensuring that CPE meet minimum performance and compatibility requirements.              


What is SIN498?

When BT Broadband launched VDSL2 ('BT Infinity' or 'FTTC') in 2009, they provided customers with a modem (such as the 'HG612'), together with a separate router (the BT 'Home Hub'). Later versions of the BT home hub combined the router and modem into one box. Other ISPs mostly still used the BT Openreach supplied modem connected to a separate router of their choice.

Having a single uniform modem device on all lines made support easier as unknown devices could be eliminated as a possible cause. In 2015, BT Openreach announced that they would cease supplying a modem for VDSL2 lines, letting ISPs or end users select their own router/modem ('wires only' service). This does away with the requirement of an engineer visit when activating or 'installing' VDSL2 service.

'BT Openreach' is the separate division of BT responsible for infrastructure (street cabinets, phone lines etc.) and distinct from 'BT Broadband' which is the ISP service, in competition with all of the other ISPs (TalkTalk, Sky, EE, PlusNet, Zen, AAISP etc.).

BT 'SIN 498' is the specification defining BT's VDSL2 service requirements in order that products meet specific standards of support and compatibility.  In the testing programme (MCT - Modem Conformance Test), devices undergo extensive testing to check if they meet the standard and comply with all of BT's requirements. The MCT covers many different aspects of a device's operation and is conducted without vendor interaction - a device is submitted and at the end it either passes or fails.


What does SIN 498 MCT testing cover?

Perhaps the most important part of the test is ensuring that the device can connect reliably to all of BT's different MSANs (the equipment in the street cabinet).  BT uses several different vendors (manufacturers) for their MSANs and each of those has several models and different software/hardware revisions.  Approval ensures that the device can connect to each of them on all line lengths up to 2600 Metres, which is the longest line length which BT consider viable for VDSL service (though you should expect relatively low speed on that length of line).  MCT also covers supplementary features of BT's VDSL network, including support for G.INP, SRA, vectoring and extensive diagnostic reporting all intended to make your connectivity more reliable and consistent.

Are DrayTek products BT SIN 498 approved?

Yes!  DrayTek's  products were submitted for testing in 2015 and received a "full pass".  The approval covers the Vigor 2860 series, Vigor 2862 series, Vigor 2865 series, Vigor 2866 series, Vigor 2760 series, Vigor 2762 series, Vigor 2620Ln, and the Vigor 130Vigor 167 VDSL modems.

DrayTek's UK lab spent many months not only ensuring full SIN498 compliance but optimising modem code and router operations specifically for UK xDSL lines to ensure the most stable and reliable connectivity.  They tested against all types of MSAN/DSLAM and line variations used by BT Openreach (the FTTC equipment in the street cabinet) to ensure that stability is consistent regardless of your local equipment. 

Earlier DrayTek Products

DrayTek's very earliest VDSL2 products (The Vigor 2850 and 2750, sold until 2013) are not upgradable to SIN498 compliance as the chipsets do not have the capability to support some of the new requirements. 


Existing DrayTek products in the field

No changes were required to hardware in order for the DrayTek routers to pass MCT, as long as you have UK hardware. Some changes were necessary in firmware so if you upgrade your router firmware to the 'SIN 498 compliant' firmware, your product is then compliant and approved.  The DrayTek SIN 498 compliant firmware is intended only for use in the UK and for UK hardware - it is not suitable or licenced for other regions or hardware.  If you are in another region, you should check with your local supplier/office for the most suitable firmware/modem code to use on your lines and to comply with any local regulations from your Telco.

Is it mandatory to use SIN 498 compliant products?

Yes; BT Openreach provide almost all VDSL lines in the UK (for all ISPs) and they do require the use of SIN498 approved devices. You are expected to have an approved device on the line in order that they can monitor performance/stability and in the event of any reported fault/problem so that they can eliminate any unknown hardware as being the cause.   SIN 498 testing ensures that devices provide adequate performance a large variety of line types and varying line quality and comply with all requirements and features within the specification.

What happens if I don't update my firmware?

If you use an unapproved product and it doesn't cause any problems to the network and you don't report any line/service issues then we think it's unlikely that your ISP or BT will take any action immediately in March 2016.   However, as there should be no reason not to update your DrayTek firmware to the SIN498 approved firmware, we recommend doing that as soon as a formal release is available in order to keep your ISP and BT happy.

It may be that in due course, BT will strictly enforce the approval requirements in order that they have more reliable reporting capability and quality statistics.   Officially, BT have warned ISPs and users that they will be specifically polling CPE (modems/routers) to check for approved devices and may take sanctions if unapproved equipment is used:

"It is prohibited to connect a device to a VDSL2 phone socket which has not passed BT's MCT (Modem Conformance Testing for SIN498).  BT will be using OAM loopback to perform diagnostics on FTTC service and identify the CPE connected. Detection of unauthorised CPE may result in the following:

• Request for removal of unauthorised CPE
• Limitation or disconnection of Service
• Lack of support when troubleshooting faults
• Abortive visit charges or SFI Customer Misoperation charges when engineers find unauthorised equipment on site.

In addition, the usage of equipment which does not comply with the SIN 498 ANFP or interferes with other subscriber's service may result in the service being terminated."                          

There are already reports of ISPs refusing to investigate reported line faults unless the customer put their approved modem onto the line however, if you do have an older BT-supplied modem, BT have stated that they "will continue to support existing modems in the field, including replacement of faulty units, until March 2017".

So, if you are an existing UK owner/operator of a Vigor2860, 2760 or Vigor 130 please upgrade to the formal SIN 498 firmware as soon as it's available  in order to satisfy BT. Their systems do interrogate the CPE (your router) and can recognise a non-compliant or unapproved device.  

What about other vendors?

If you have non-DrayTek VDSL products, check with your vendor about their MCT status and whether they have approval. Like with DrayTek products, they may provide updates to existing products so that you are then using approved CPE.  There is no self-certification; a vendor may say that they are 'compliant' with SIN498, but that does mean that they have passed MCT. We know that several other vendors (e.g. Cisco, Technicolor) have also now received formal MCT approval on products but do check with your supplier.