VSS V3 no longer connects after upgrading from ADSL2 to VDSL

[gryfon]

I am using V3 SureSignal with ID: 40130440767 with a fixed "In service" light and a flashing power light.  This unit has performed flawlessly for many months (nearly 2 years now I believe) and we are in a zero-GSM-signal location so any help will be extremely gratefully received.

My UK ISP is Eclipse Internet, I have the same fixed IP as before upgrading.  Since upgrading to a Fibre To The Cabinet (FTTC) connection from ADSL 2 the Sure Signal no longer connects to the Vodafone network.
On the 30th April a BT engineer upgraded my BT faceplate and installed a new modem to provide us with a FTTC connection.  I am using a TP-Link Archer C5 AC1200 DSL router with this modem, on a PPPoE connection.

I have tried:

Re-registering the SS.  The registration process always completes and always within 15 minutes, makes no difference after 24 hours still the same flashing sequence.

Trying a different ethernet cable - makes no difference.

Trying a different internet connection (ADSL 2 in a different house and ISP on the same street) - works perfectly.

Adding all the recommended ports into the TP Link routers firewall - I have tested these using port-forwarding tools as recommended and they work correctly.

Resetting the SS manually (press and hold for 20 seconds) several

times.

Updating the firmware on my router - there is only 1 available and I have applied it.

As per other requests, here are the results of your recommended tests for these issues:

Speedtest.net results:
35.42 Mbps
1.70 Mbps

Pingtest.net results:
Packet Loss 0%
Ping: 33ms
Jitter: 4ms
Grade A

IP: 82.152.45.17

Traceroute results:
Tracing route to 212.183.133.177 over a maximum of 30 hops

  1    <1 ms    <1 ms    <1 ms  192.168.2.1
  2     *        *        *     Request timed out.
  3    16 ms    15 ms    15 ms  lo0_ecldsl-bba7.th.eclipse.net.uk [82.153.1.69]

  4    16 ms    16 ms    15 ms  91.85.10.101
  5    16 ms    16 ms    16 ms  62.164.130.53
  6    20 ms    16 ms    15 ms  vl-38.lon-th1cr.spn.kcom.com [86.54.183.249]
  7    18 ms    19 ms    18 ms  lndgw2.arcor-ip.net [195.66.224.124]
  8    18 ms    18 ms    17 ms  85.205.0.93
  9     *        *        *     Request timed out.
 10     *        *        *     Request timed out.
 11     *        *        *     Request timed out.
 12     *        *        *     Request timed out.
 13     *        *        *     Request timed out.
 14     *        *        *     Request timed out.
 15     *        *        *     Request timed out.
 16     *        *        *     Request timed out.
 17     *        *        *     Request timed out.
 18     *        *        *     Request timed out.
 19     *        *        *     Request timed out.
 20     *        *        *     Request timed out.
 21     *        *        *     Request timed out.
 22     *        *        *     Request timed out.
 23     *        *        *     Request timed out.
 24     *        *        *     Request timed out.
 25     *        *        *     Request timed out.
 26     *        *        *     Request timed out.
 27     *        *        *     Request timed out.
 28     *        *        *     Request timed out.
 29     *        *        *     Request timed out.
 30     *        *        *     Request timed out.

My ISP is not blocking the SS and have confirmed it should still work as normal.  I have read a number of other forum posts relating to a packet fragementation feature on a number of Draytek Routers being "off" by default (and having been fixed with a firmware update) and am beginning to think something like that is the most likely cause.  Since I cannot set an MTU of 1500 (FTTC requires 1492 and will not connect otherwires) this fits in with symptoms mentioned by Draytek modem users.

Is there anything else I can try or any other advice you can give me?  It's really painful to now have a 34Mbps download speed and yet no GSM connection, let alone 3G!

[Retired-Sarah]

Hi @gryfon

Welcome to the eForum.

As you’ve tried the Sure Signal in a different location and it’s resulted in a connection, this rules out any fault with the device itself.

It seems as though the Sure Signal is not compatible with the upgrade you’ve had.

Thanks,

Sarah

[gryfon]

Hmmm...

There are many other posters on this forum who have got their SureSignal V3 working with a FTTC connection successfully (BT Infinity connections for one).  If the device is merely making a VPN connection back to Vodafone and the traceroute doesn't make it all the way to the Vodafone network, then surely it means something in between is stopping the connection?  Is there anything else I can try in the router for example?  Do you know if anyone else who is using a TP Link router like mine successfully with a SS?

[Jenny]

@gryfon

Unfortunately there’s nothing more we can do or suggest from here.

You’ll need to speak with your ISP to see if they have any further suggestions.

[gryfon]

I've spoken with Eclipse Internet and they've confirmed there's no reason why the connection shouldn't work. 

If you understand the underlying technology and the very minor change involved, it does make sense that where it worked over an ADSL connection routing their systems, there should be no difference over a FTTC connection through the same network.

Reading around the issue in these and other forums it's become apparent that having a router which permits "fragmented packets" (sometimes an actual setting or tick box named "Allow fragmented packets" as seen in some Draytek routers) needs to be enabled for FTTC style connections.  Some BT Home Hubs do not permit fragmented packets, there are posts on these forums going back a few years regarding these very issues.

I have also discovered that some people have found their TP Link Router does not permit fragmented packets and has no setting to allow them.  I will check this evening with TP Link:

a)  If they have new firmware for my particular router.
b)  If others have reported femtocell problems on FTTC connections in the UK over their hardware.

and report back with my findings.

[gryfon]

I have updated the firmware to the latest version and still have the same problem.

I'm increasing convinced that the problem is having a separate modem and router - I have read reports that the modem isn't translating the NAT correctly and the lack of people complaining about TP Link modems generally on this forum, along with others having problems with the 2-box solution both appear to corroborate that.  Tomorrow I will buy a replacement all-in-one VDSL modem to connect directly to the phone socket and by-pass the BT Openreach modem altogether.

[gryfon]

Real life has intruded for a while...
I've removed the BT OpenReach modem and replaced it and my other TP Link router with an all-in-one DSL modem, an Asus DSL-N6U. Not cheap but covers everything I need. Initially the SureSignal performed even worse than before - the SS3 would pickup an IP address from DHCP then drop it after a few moments. At this point I was starting to lose hope. At least it would pickup an IP address with the old router!
I have an Apple TV connected to the SureSignal pass-through port which worked fine and picked up an IP address without issue which is even stranger.
Finally I replaced the cable again, from the SS to the router and rebooted the SS3 and after 4-5 hours, has now finally successfully connected to the Vodafone network again.

So watch out if you're moving from ADSL to FTTC. It would be immensely useful if someone at Vodafone could compile and post a list of modems which have been reported as working with SureSignals - this would have saved me a lot of time and money.