Calling for Clarity on Openreach’s Broadband Modem Conformance Testing

Openreach’s (BT) Modem Conformance Testing (MCT), which ensures that a router / modem device is approved for use on their hybrid fibre (FTTC) UK broadband network, needs to become much more accessible and transparent for consumers. Unapproved kit can also carry the risk of disconnection.

Probably most of the people I know (outside of ISP circles) who use an FTTC broadband connection over Openreach’s network, the bulk of which are your typical IT / Networking style professionals or enthusiasts, have plugged a router into their Master Socket that’s NOT on the operator’s approved list of VDSL devices. But not one of them was aware of this.

In fairness, it’s not their fault. After all, how could they know? Openreach does not publish an up-to-date version of their approved list for public consumption on their website and neither do they reveal which devices were rejected or why. Instead the responsibility tends to be passed down the line to ISPs, yet the vast majority of those don’t publish the information either (many bundle their own pre-approved kit and so perhaps feel no need).

However, most ISPs, especially smaller providers, do still allow you to use a third-party VDSL2 router if so desired. This flexibility is good for the competitive hardware market and consumers, who like choice because the routers offered by providers tend to be a bit on the naff side. Nevertheless it is all too easy for somebody to buy an unapproved device.

You see it’s possible to connect a router that can actually cause problems for Openreach’s network (e.g. interference), which might even impact other users. But most of the time it’s the end-users own connection that pays the price for connecting an incompatible device, which could be reflected in various different ways from connectivity problems to performance loss etc.

A prime example popped up this week when Openreach warned ISPs (here) that a specific modem/firmware combination on unapproved end customer modems was causing an “issue” in their VDSL2 street cabinets (DSLAMs).

Openreach Briefing NGA042/17

This briefing is to inform CPs that we have a number of DSLAMs in the live network that are not properly reporting to the Openreach Dynamic Line Management (DLM) System

A specific modem/firmware combination on end customer devices which have not been approved for use on our network and have not been through our Modem Conformance Tests (MCT) is or appears to be causing an issue in the DSLAMs that means they do not correctly format the data transmitted from the DSLAM to our DLM systems. The DLM system then cannot interpret the data for all lines on that DSLAM.

The briefing for this was closed to the public, although the private document states that “Openreach will not enter into any discussions about the modems involved” (they don’t appear to name the device). Openreach also warns that they will “disconnect” the service if it’s identified that one of the non-approved devices is in use (we assume they could easily identify such routers via loopback testing).

We know from past experience that Openreach can also request that the device itself be disconnected (rather than shut down the entire service) or they could refuse to fix problems. Likewise they could conceivably levy charges if the device is found to be the cause of a fault investigation (i.e. requiring an engineer call out or abortive visit etc.). In other words, it’s wise to use an approved router when requesting ISP support.

At this point the briefing reminds ISPs “that they should advise their end customers to only connect the MCT approved CP provided device or the Openreach VDSL to their GEA-FTTC Service,” which is fair but the briefing does not name the device/firmware involved and Openreach could have easily made this public themselves. Doing so would have helped to inform consumers and thus reduce the problem.

We should point out that a fix is in development for the fault mentioned above. New router firmware is being tested, while Openreach could also fix it on their ECI/Huawei network or DLM system in order to cope with the issue when spotted. But one problem with relying on router firmware is that many end-users don’t bother to manually update their kit, which means that Openreach may still need to tweak their network.

The other problem with Openreach’s approved modems list is that it’s quite out of step with modern hardware (we’ve pasted a copy of BT Wholesale’s list below that covers many of the approved models but it is not as extensive as the one that Openreach keep hidden). Enthusiasts tend to buy the latest kit but many of the best models cannot be found on the operator’s list, which is fairly short.

We should add that unapproved modems usually work just fine on Openreach’s network and you’re unlikely to have a problem but, as the example above shows, faults do sometimes occur and you could get in trouble. On the other hand, approved modems aren’t necessarily bastions of perfection and issues do sometimes arise on those too, which may still cause problems for Openreach’s network.

In our view both Openreach and ISPs need to be more transparent about the list of approved modems, as well as identifying any devices with known faults or those that have been rejected. At the same time we’d like to see Openreach becoming more proactive by testing a wider range of new models, although this would require manufactures to engage more closely and that could be tricky to encourage (MCT testing has gained a reputation for being painfully slow but they are improving it).

Transparency also means that fewer consumers may end up choose a model that hasn’t been approved, which should in theory reduce the potential for compatibility problems, while also making Openreach’s life easier and encouraging manufacturers to engage more closely.

We did ask Openreach for their thoughts and are still awaiting a reply.

Approved VDSL Modems / Routers [BT Wholesale] (Oct 2017)

AVM

FRITZ!Box 3490

Arcadyan

Brightbox 2

Cisco

1921
897VA
C897VA-K9
CISCO887VA-K9
CISCO887VA-M-K9
CISCO887VA-SEC-K9
C887VAM-K9
C887VA-W-E-K9
C887VAM-W-E-K9
C887VA-V-K9
C887VA-V-W-E-K9
C887VA-CUBE-K9
C887VAG+7-K9
C887VAMG+7-K9
C887VAGW+7-E-K9
C887VA-WD-E-K9
C887VAG-4G-GA-K9
C897VA-M-K9
C897VAW-E-K9
C897VAM-W-E-K9
C897VAG-LTE-GA-k9
C897VAMG-LTE-GA-K9
EHWIC-VA-DSL-A
EHWIC-VA-DSL-M
NIM VA

Draytek

Vigor 2860
Vigor 2860vn Plus
Vigor 2860vac
Vigor 2860n
Vigor 2860n Plus
Vigor 2860L
Vigor 2860Ln
Vigor 2860ac
Vigor 2862
Vigor 2760
Vigor 2760vn
Vigor 2760n
Vigor 130

Huawei

HG633
AR129
AR129W
AR129GW-L
AR509G-L-D-H
AR169FVW
AR169FGW-L
AR169FGVW-L
AR169F

Kenton Comtrend

VR-3030
KBR1645 Velocity Lite

Kenton OneAccess

1321 Ethernet Access device
1322 Ethernet Access device
1645 Ethernet Access device
One 270 AV2
One 425 AV2
One 445 AV2
One 540 AV2
One 700 AV2
One 1540 AV2

Netgear

D7000
D7800

Technicolor

TG589Vac
TG579vac v2
TG588v2
TG589Vac v1
TG589Vac v2
TG589vac
TG789Vac v1
TG789Vac v2
TG789vac
DGA1430

Virtual Access

GW33110-V

ZyXEL

VMG8324-B10A
VMG8924 (Z-400UK)
VMG1312-B10A
VMG1312-B10D
VMG3925 – B10B

NOTE: Some routers bundled by ISPs may be missing from this list as it tends not to include those that are customised and branded to specific ISPs (i.e. those you can’t officially buy in the shops), while others may show up under a different model code.