BT Infinity and Sure Signal.

[Jimfew]

I have just changed ISP to BT Infinity. As expected, my Sure Signal has failed. I have tried all sorts of resets and have asked Vodafone support to reset my device and do a network reset. I have also done a hard reset myself. It still does not work. I have opened all the necessary ports on my router (not the BT hub but a Draytek 2820).

I wonder if I also need to ask BT to open ports on their servers? Is this necessary? My old ISP, Be*, did not restrict any ports but BT may be different.

Can anyone advise me.

My VSS number is 21221070754

Can anyone list all the ports the VSS needs to be open (as up to date as possible).

Many thanks, Jim.

[trolleybus]

Hello,

Same kit as you so dived into the DrayTek 2820 to change the DFcheck flag.

The entry wan DF_check /? returns

%DF bit check is Disable!

What does that mean please? I assume it means already disabled but equally it could mean to use the Disable command.  But how?

I would very much appreciate your feedback.

For the record the LAN address of the SS has is MAC bound to IP and also these ports are open:

4500 UDP

500 UDP

8 TCP

1723 TCP and UDP

50 TCP

I am always reluctant to reboot the router but I guess I should and also power down/up SS,  At this stage is a hard reset called for?

Is there anything else that I should configure in the router< I have currently the NTU set as 1492.

I have made sure that my port redirection request are for WAN2 !

David Bradley

[trolleybus]

The command was actually

wan DF_check off

So a power recycle then took place. When the internet was established, VSS was rebooted. Usual flashing of lights for around 15 minutes only to be left with the power light on. Leaving the office now but not expecting it to be magically working in the morning.

All very frustrating and out of guidance of what to do next.  Anyone with any ideas here?

David  

[MidnightStar]

I purchased a VSS and could not get it working with PPPoE, then I found this thread and saw all the problems people are having.

My ISP provided the OpenReach HG612 modem and a Zyxel router.

I have replaced the Zyxel router with a £16.00 TP-Link TL-R460 router and after setting up the log in etc. the VSS works with no other changes needed.

Hope that helps

[Jimfew]

We think that the SS will only work on UK PPPoE (MTU 1492) with any router than can igonre the DF_Check flag and fragment the packets. This flag, in the Draytak 2820 router is only accessible through telnet commands and only accepts a change when you do a hard reset. Even then, the SS takes an overnight wait before it finally sets up.

The DF_Check flag is one that allows you to tell the router to look at the DF flag in the header of each packet. DF is a "DO NOT FRAGMENT" bit which tells any active device that the packet must be passed on without any breakup or fragmentation. Curiously Draytek have implemented the logic of this in reverse so you need to disable this function to allow the Draytek router to fragment the packets. Since the VSS, as a preset fixed setting, sets the DF flag and any router that checks this flag will be unable to fragment the packet unless it ignors it, as it does if you turn off the DF_Check function in the Draytek 2820.

If your router does not ignor the flag bit, it cannot fragment the "jumbo framed" packets (MTU 1500) down to the smaller MTU 1492 required for PPPoE in the UK, in my case BT Infinity, and is unable to do anything but discard the packets. This is seem on the VSS lights a a single red light on and the others off.

This problem is manageable for some people who have older or cheaper routers which just fragment the packets anyway. For more modern routers the problem is you need one that will allow the packets to be fragmented, as does my 2820 but it took ages to find the correct command and set it up.

The long term solution is that Vodafone implement MTU Path Discover on their VSS as a mod and allow packet sizes other than 1500 to be sent out from the source. Until then, erveyone will be in the lap of fortune as to whether they get it to work and some will need to purchase alternative routers that have been shown to work by users on this forum.

[madhatter2426]

Hi all, using the VSS ver 2 and a Billion 7800n. No problems with the VSS. Have not had to forward and ports. My BT hub ver 3 also works with no problems. Both the Billion and the HH3 are default set ups. Billion connecting to the BT Modem via the ewan port of the 7800n and PPPoE.

[saltyzip]

Can you confirm you still have the 7800N working with the VSS v2 as it won't work for me?

I have raised a ticket with Billion UK around the MTU points mentioned in this post for clarification.

[madhatter2426]

Yes vss2 works fine with my billion 7800n. Never had to forward ports or anything.

[simon_perkins]

Thanks. I got a SureSignal V3 working with PPOE:

http://forum.vodafone.co.uk/t5/Vodafone-Sure-Signal/Sure-Signal-not-transmitting-a-3G-signal/m-p/229...

The DF_check flag seemed to be disabled by default but using 'wan Df_check off' and a power recycle seemed to do the trick.

I've battling with this for weeks!

BTW, no port fowarding or DMZ is needed.

[Jimfew]

Actually the problem is with the VSS as it does not meet the spec for PPPoE in the UK, which means it cannot work with the BT Infinity system. However, it seems some router manufacturers have seen this issue and allow 1500 MTU (so called Jumbo packets) to pass through by fragmenting them to 1492 MTU which is the UK standard. I think that Draytek have not modified it's routers and have not seen this issue and just reject Jumbo packets which are outside the PPPoE spec.

I have tried the BT fibre router, the Drayteks 2820 and 2750 and a modern Netgear. All fail. I am told by BT that the issue might be down to their newer DSLAMs which use Broadcom chipsets and reject any jumbo packets as they are outside spec (One BT tech person said it also rejects fragmented packets but I find this hard to believe). So even routers that can pass the Jumbo packets unchanged will still not pass the DSLAM in the cabinets (for FTTC systems).

It might be possible for a router manufacturer to "fudge" the issue by breaking up the Jumbo packets into PPPoE compliant ones and passing them through (this will need special attention when using any VPN passthrough). I hope that Draytek might yet come to our rescue and make a firmwear mod.

However, the root cause of this problem is that the VSS is not designed to work with PPPoE 1492 MTU stsyems. This nees to be amended and I understand that a relatively simple firmwear mod could make all these issues go away if only Vodafone would do the upgrade. As can be seen elsewhere there are more and more people using the newer Infinity products using PPPoE and Vodafone cannot ignore this change for ever.

[s4vva]

Hi, if you look through my previous posts you will notice I had exactly the same issues with a PPPoA and PPPoE standard adsl connection (it worked on oA but not oE).

We recently upgraded to BT Infinity knowing we were risking the Sure Signal possibly not working. Too our surpise in the office the SS worked fine for three months! However recently the SS stopped working and we have been stuck with the steady power light since.

It's odd as I was never expecting it to work in the first place (we have a Draytek 2820, BT Infinity which is of course PPPoE). Nothing on our network has changed so it is really frustrating.