Speed starts normal then shoots down by 20mbps

Have Zen bought in any sort of throttling lately ? If not then any ideas what could be the issue ? I notice when I do a speed check my usual 60mbps speed now starts at that, but within seconds it is dropping down to 38mbps, it never used to do this. I first noticed it last night, around 5am, so I know it is not congestion. My IP Profile is still the same as before so that hasn't dropped.

I am on the 80mbps unlimited FTTC package. I use a wired connection.

Just wondered before I contact them if anyone might know the reason ? Thanks.

Happening to me too. Rebooting the router seemed to work when it happened a week or so ago, but it's started again. Speed dial on the speed test jumps to around 60 Mb/s then falls down to 30 or so. Upload speeds are about normal, at 18 Mb/s

Mine is the other way around. Starts low and builds up slowly to a max around 30-40% into the speedtest. Upload is fine.

Just an update on this, it's still ongoing. I went as far as to swap routers entirely, and I get the same pattern of behaviour, an initial jump to normalish speeds, then a slow decline to around 30 Mb/s where it levels off. Uploads are normal at 18 Mb/s.

I have contacted Zen support, so let's see what ensues.

Update 2
After a re-synchronisation, my speeds are back to normal.

Just one of those internet mysteries I suppose.

How interesting. My line is experiencing the same type of issue as you guys. Syncs at 60Mb and download starts at that and then gets throttled to 50% of the line speed.

I rebooted the modem but it didn't help...

I've contacted support. Hopefully they will find out what the issue is.

In reply to a post by RobWatts:

Update 2
After a re-synchronisation, my speeds are back to normal.

Just one of those internet mysteries I suppose.

Probably obtained a different routing, some routes on Zen are slower and have more latency than others.

Another one here ... seems to be a growing menace on the Zen side of things.

Had it early June, then improved and now back again .. despite resync.

Annoying is this is down to 30Mb from a 55 sync .... used to sync at full whack before crosstalk so 75 down to 30 hurts to say the least !

I spoke to Zen support. They say there have been a number of customers with very similar problems. My support representative is hopefully putting together a case that he can give to his network operations team to investigate.
I have a 60Mb sync too which goes down to 30Mb, after a second or so at the full 60Mb. I've tried reconnecting several times. Resyncing my circuit hasn't helped one little bit. My traceroute if it helps anyone...

1 192.168.178.1 (192.168.178.1) 0.370 ms 0.271 ms 0.254 ms
2 vt1.cor1.lond1.ptn.zen.net.uk (51.148.72.21) 7.778 ms 9.078 ms 9.778 ms
3 ae-12.cor1.leed1.ptn.zen.net.uk (51.148.73.22) 12.936 ms 12.920 ms 12.714 ms
4 ae-26.cor2.roch1.ptn.zen.net.uk (51.148.73.51) 15.909 ms 15.808 ms 16.068 ms
5 ae-25.cor1.roch1.ptn.zen.net.uk (51.148.73.49) 15.941 ms 15.939 ms 19.304 ms
6 xe-3-1-0.cr2.sp-roch.zen.net.uk (51.148.73.61) 15.006 ms 15.058 ms 15.245 ms
7 ae8-0.ar3.sp-roch.zen.net.uk (62.3.81.238) 14.990 ms 15.001 ms 14.802 ms
8 up1.1-pub.zen.net.uk (62.3.80.130) 15.165 ms 15.122 ms 15.224 ms
9 172.17.41.2 (172.17.41.2) 15.446 ms 15.534 ms 15.014 ms
10 web01.web.zen.net (212.23.8.83) 15.260 ms 15.139 ms 14.965 ms

OK I now have full speed again ... couple of router swaps no change .. back to orginal and full service.

Route is :

1 <1 ms <1 ms <1 ms fritz.box [192.168.0.1]
2 103 ms 99 ms 87 ms vt1.cor1.lond2.ptn.zen.net.uk [51.148.72.23]
3 92 ms 86 ms 83 ms ae-2.cor1.lond1.ptn.zen.net.uk [51.148.73.2]
4 79 ms 94 ms 94 ms ae-1.agg4.lond1.ptn.zen.net.uk [51.148.73.84]
5 125 ms 98 ms 95 ms vl-50.ae6.cr1.th-lon.zen.net.uk [51.148.73.57]
6 102 ms 95 ms 96 ms xe-2-0-0-172.dr1.lr-slo.zen.net.uk [62.3.80.102]
7 75 ms 92 ms 87 ms cache03.dns.zen.net.uk [212.23.6.100]

It's coming up to a week now and Zen still haven't told me what the problem is or what I can do to resolve the issue. I'm seriously thinking about changing to a different ISP.

And so it transpires that Zen support have said they believe my equipment is causing this issue and they haven't done anything to get it sorted out. I even tried making a complaint, but they ignored that.

I can't believe I've been paying so much money for this complete lack of service.

Tim

They sent me a "trial" router .. made no difference.

Can you try a resync tonight see what happens, wondering if they are priortising a new router at all ?

Do a tracert to echo.zen.co.uk (just so we both know going to same server).

Well I guess they're trying... I was quite amused when Zen told me that on my FTTC circuit (which syncs at 63Mb) was quite within normal service parameters with a speedtest (from Zens servers of 31Mb/s!

Here's the traceroute to echo.zen.co.uk. I'll try resyncing again but I did it on Sunday, left it off for an hour then again on Monday morning for 4 hours (though to be honest that was cabinet wide) and did 4 ppp resyncs...

1 192.168.178.1 (192.168.178.1) 0.409 ms 0.274 ms 0.283 ms
2 vt1.cor2.lond2.ptn.zen.net.uk (51.148.72.24) 11.472 ms 7.738 ms 6.569 ms
3 ae-7.cor2.lond1.ptn.zen.net.uk (51.148.73.12) 108.523 ms 45.539 ms 6.918 ms
4 ae-2.agg4.lond1.ptn.zen.net.uk (51.148.73.86) 6.642 ms 6.644 ms 6.550 ms
5 vl-50.ae6.cr1.th-lon.zen.net.uk (51.148.73.57) 6.307 ms 6.453 ms 6.614 ms
6 xe-2-0-0-172.dr1.lr-slo.zen.net.uk (62.3.80.102) 6.739 ms 7.248 ms 7.288 ms
7 cache03.dns.zen.net.uk (212.23.6.100) 7.283 ms 7.114 ms 7.240 ms

Well mine shafted again .. resynced itself at 2AM and is now at half speed.

I notice the first hop has changed ... starting to feel very much like routing to me.


1 <1 ms <1 ms <1 ms fritz.box [192.168.0.1]
2 50 ms 17 ms 17 ms vt1.cor2.lond1.ptn.zen.net.uk [51.148.72.22]
3 17 ms 17 ms 17 ms ae-2.agg4.lond1.ptn.zen.net.uk [51.148.73.86]
4 17 ms 17 ms 17 ms vl-50.ae6.cr1.th-lon.zen.net.uk [51.148.73.57]
5 18 ms 18 ms 18 ms xe-2-0-0-172.dr1.lr-slo.zen.net.uk [62.3.80.102]
6 18 ms 18 ms 17 ms cache03.dns.zen.net.uk [212.23.6.100]

Edited by deleted (Fri 12-Jul-19 20:15:46)

I'd agree and very interestingly Zen have just altered the routing of my link. It's very different than the one I was getting before.

At least initially the link is back to its former performance.

1 192.168.178.1 (192.168.178.1) 0.375 ms 0.271 ms 0.258 ms
2 losubs.subs.bng2.th-lon.zen.net.uk (62.3.80.21) 6.175 ms 6.056 ms 6.760 ms
3 ae1-182.cr1.th-lon.zen.net.uk (62.3.86.80) 6.080 ms 69.185 ms 40.670 ms
4 xe-2-0-0-172.dr1.lr-slo.zen.net.uk (62.3.80.102) 6.809 ms 6.957 ms 6.809 ms
5 cache03.dns.zen.net.uk (212.23.6.100) 6.571 ms 6.629 ms 6.610 ms

In reply to a post by timl:

2 losubs.subs.bng2.th-lon.zen.net.uk (62.3.80.21) 6.175 ms 6.056 ms 6.760 ms

Haven't seen that second hop before on Zen. New network equipment maybe?

I am on zen 80/20 and i get 30mbps download here, don't know what to do here.

http://tbb.st/1563119075672608455

My trace route is below.

Tracing route to www.google.co.uk [172.217.169.3]
over a maximum of 30 hops:

1 1 ms 1 ms <1 ms fritz.box [192.168.178.1]
2 14 ms 14 ms 13 ms vt1.cor1.lond2.ptn.zen.net.uk [51.148.72.23]
3 14 ms 14 ms 13 ms ae-2.cor1.lond1.ptn.zen.net.uk [51.148.73.2]
4 15 ms 16 ms 14 ms ae-3.agg1.lond1.ptn.zen.net.uk [51.148.73.4]
5 14 ms 14 ms 14 ms 72.14.217.190
6 14 ms 13 ms 13 ms 108.170.246.129
7 15 ms 15 ms 14 ms 209.85.241.93
8 13 ms 13 ms 15 ms lhr25s26-in-f3.1e100.net [172.217.169.3]

edit

I have rebooted the router, and now i am getting the right speed below.

http://tbb.st/1563137760539396955

Edited by deleted (Sun 14-Jul-19 21:57:25)

Is everyone still on track .. mine has dropped back to 30mb ceiling.

I have requested the ability to leave without penalty as per their charter ... 2 months of this and the latest email asked me to use the "master socket" .... sigh.

Continuing to be good here.

Text

1 23 45 67 8

traceroute to echo.zen.co.uk (212.23.6.100), 64 hops max, 52 byte packets  1  192.168.0.11 (192.168.0.11)  0.600 ms  0.362 ms  0.287 ms 2  vt1.cor2.lond2.ptn.zen.net.uk (51.148.72.24)  25.458 ms  24.894 ms  24.462 ms  3  ae-7.cor2.lond1.ptn.zen.net.uk (51.148.73.12)  25.260 ms  27.870 ms  24.950 ms 4  * * *  5  vl-50.ae6.cr1.th-lon.zen.net.uk (51.148.73.57)  25.207 ms  24.834 ms  24.763 ms 6  xe-2-0-0-172.dr1.lr-slo.zen.net.uk (62.3.80.102)  25.452 ms  25.629 ms  25.468 ms  7  cache03.dns.zen.net.uk (212.23.6.100)  25.545 ms !Z  25.575 ms !Z  25.514 ms !Z

Current sync: 67733 / 20000
Current IP Profile: 65264

In reply to a post by BlizzardUK:

I notice when I do a speed check my usual 60mbps speed now starts at that, but within seconds it is dropping down to 38mbps, it never used to do this.

Have you got a screenshot of the speedtest graph showing how it drops? And I assume that the "sync speed" as reported by your modem is a bit over 60Mbps?

This is just a guess, but it sounds to me like Zen could have applied a 40Mbps BRAS profile to your line.

In reply to a post by BlizzardUK:

My IP Profile is still the same as before so that hasn't dropped.

By this, I guess you mean you've checked at BT Wholesale? It is possible Zen's own BRAS might be applying the wrong profile, e.g. a bug in their RADIUS servers.

If resyncing the line can make the problem go away sometimes, that would suggest Zen sometimes applying the wrong profile when the session starts, e.g. if they have a pool of RADIUS servers and one of them is misconfigured.

Same all good ... I am now getting full speed all the time.

Had a "change" applied to the line by a engineer .. dunno what it was but it caused a rsync and all been fine since.

In reply to a post by candlerb:

In reply to a post by BlizzardUK:

I notice when I do a speed check my usual 60mbps speed now starts at that, but within seconds it is dropping down to 38mbps, it never used to do this.

Have you got a screenshot of the speedtest graph showing how it drops? And I assume that the "sync speed" as reported by your modem is a bit over 60Mbps?

This is just a guess, but it sounds to me like Zen could have applied a 40Mbps BRAS profile to your line.

In reply to a post by BlizzardUK:

My IP Profile is still the same as before so that hasn't dropped.

By this, I guess you mean you've checked at BT Wholesale? It is possible Zen's own BRAS might be applying the wrong profile, e.g. a bug in their RADIUS servers.

If resyncing the line can make the problem go away sometimes, that would suggest Zen sometimes applying the wrong profile when the session starts, e.g. if they have a pool of RADIUS servers and one of them is misconfigured.

nothing would surprise me now if im honest. after being screwed around and suffering from a bad connection for a gamer im now on something that could be deemed to be ok. from constant packetloss and jitter to this.


so it wasnt bt all along.


lisa the solicitor and all the jhons working at zen have a lot to answer for.

edit there goes my ok connnection...........

Edited by deleted (Sat 20-Jul-19 21:25:18)

My connection is good at the moment, but have the same routing to echo.zen.co.uk.

1 <1 ms <1 ms <1 ms fritz.box [192.168.0.1]
2 18 ms 16 ms 14 ms vt1.cor2.lond1.ptn.zen.net.uk [51.148.72.22]
3 15 ms 14 ms 14 ms ae-2.agg4.lond1.ptn.zen.net.uk [51.148.73.86]
4 14 ms 14 ms 14 ms vl-50.ae6.cr1.th-lon.zen.net.uk [51.148.73.57]
5 16 ms 15 ms 15 ms xe-2-0-0-172.dr1.lr-slo.zen.net.uk [62.3.80.102]
6 15 ms 15 ms 15 ms cache03.dns.zen.net.uk [212.23.6.100

My router has not resynched since June 26th.