topic Re: Speed HALFED again in IPv6 Trial

Speed HALFED again

HairyMcbiker — Mon, 17 Mar 2014 16:49:56 GMT

my download speed is down to sub 40Mb again.
What has happened?
http://www.speedtest.net/my-result/3376933360

Re: Speed HALFED again

chrcoluk — Mon, 17 Mar 2014 16:58:02 GMT

I think posted in wrong section.

Re: Speed HALFED again

HairyMcbiker — Mon, 17 Mar 2014 17:03:42 GMT

Why I am ON IPV6. All results are meant to be posted here.
The last time this happened was an error by PN.

Re: Speed HALFED again

chrcoluk — Mon, 17 Mar 2014 18:57:55 GMT

ok thanks for clarifying.

Re: Speed HALFED again

HairyMcbiker — Sat, 05 Apr 2014 11:33:33 GMT

Same again:
Result on ipv6:
Result on ipv4: my normal login:

This was just by changing my login details.
Now it MIGHT be gateway lottery again, but PN says this is a thing of the past

Re: Speed HALFED again

AndyH — Sat, 05 Apr 2014 11:36:57 GMT

Are you on fibre or ADSL?

Re: Speed HALFED again

jelv — Sat, 05 Apr 2014 11:44:09 GMT

Speeds over 24Mbps can only be fibre!
@Hairy McBiker Have you checked the current line speed on the portal and compared it with the IP Profile reported by the BT diagnostic test?

Re: Speed HALFED again

AndyH — Sat, 05 Apr 2014 11:49:00 GMT

Sorry...brain freeze...
What is your MTU on your router if you run this command ip rt6advd iflist ?
Edit: It appears that speedtest.net is dual stacked but the test runs over v4 - so that should rule out a MTU problem

Re: Speed HALFED again

HairyMcbiker — Sat, 05 Apr 2014 13:52:51 GMT

From my members page:
Estimated line speed:
There's no speed estimate currently held on your account.
Current line speed:
77.4 Mb
Not done a BT test as it seems fine on ipv4. (Which I am still on)
Currently:

I will drop this connection and re-login as ipv6

Re: Speed HALFED again

HairyMcbiker — Sat, 05 Apr 2014 13:58:02 GMT

MTU bits:

{Administrator}=>ip rt6advd iflist
Flags Legend: ttached anaged ther - Def. Rtr. Pref. ow / Medim / igh
Interface        AdvInterval Lifetime Reachable  Retrans.   CurHopLimit LinkMTU Flags  NextRA
---------------- ----------- -------- ---------- ---------- ----------- ------- ------ --------
LocalNetwork      200 /  600     1800          0          0          64       0 [A.OU]      403

Retest using ipv6
So a little slower but not the major difference there was before, however the ping has more than doubled.

Re: Speed HALFED again

AndyH — Sat, 05 Apr 2014 14:15:36 GMT

What if you ping a site like bbc.co.uk in v6 (ping -6 ipv6.bbc.co.uk )? How does that compare to normal bbc pings?

Re: Speed HALFED again

HairyMcbiker — Sat, 05 Apr 2014 14:25:09 GMT

hairybiker@Duo:~$ ping bbc.co.uk
PING bbc.co.uk (212.58.244.18) 56(84) bytes of data.
64 bytes from fmt-vip72.telhc.bbc.co.uk (212.58.244.18): icmp_seq=1 ttl=55 time=19.5 ms
64 bytes from fmt-vip72.telhc.bbc.co.uk (212.58.244.18): icmp_seq=2 ttl=55 time=18.7 ms
64 bytes from fmt-vip72.telhc.bbc.co.uk (212.58.244.18): icmp_seq=3 ttl=55 time=19.0 ms
64 bytes from fmt-vip72.telhc.bbc.co.uk (212.58.244.18): icmp_seq=4 ttl=55 time=18.5 ms
64 bytes from fmt-vip72.telhc.bbc.co.uk (212.58.244.18): icmp_seq=5 ttl=55 time=19.0 ms
--- bbc.co.uk ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4001ms
rtt min/avg/max/mdev = 18.513/18.960/19.507/0.371 ms
hairybiker@Duo:~$ ping6  ipv6.bbc.co.uk
PING ipv6.bbc.co.uk(2001:4b10:bbc::2) 56 data bytes

still waiting for a reply, been over a minute now.

Re: Speed HALFED again

AndyH — Sat, 05 Apr 2014 14:50:49 GMT

Sorry - my mistake, that BBC IPv6 IP isn't responding to pings.
Try ipv6.thinkbroadband.com (2a02:68:1::4)

Re: Speed HALFED again

HairyMcbiker — Sat, 05 Apr 2014 14:53:49 GMT

It seems to have settled down again, back to 20ms.

Re: Speed HALFED again

chrcoluk — Wed, 09 Apr 2014 11:12:47 GMT

Quote from: AndyH
Sorry...brain freeze...
What is your MTU on your router if you run this command ip rt6advd iflist ?
Edit: It appears that speedtest.net is dual stacked but the test runs over v4 - so that should rule out a MTU problem

andy you figured a way to get our asus routers to set a seperate ipv6 mtu to ipv4 mtu?

Re: Speed HALFED again

AndyH — Wed, 09 Apr 2014 11:49:23 GMT

Not yet...I am checking with Asus in Taiwan on that.
There's a few IPv6 things I've asked them to look at (MTU/Packet Too Big Messages/Ping Spikes).

Re: Speed HALFED again

MJN — Wed, 09 Apr 2014 12:28:24 GMT

Quote from: chrcoluk
andy you figured a way to get our asus routers to set a seperate ipv6 mtu to ipv4 mtu?

I haven't been through the thread so I might be taking that question out of context but it wouldn't make sense to have separate MTU values for IPv4 and IPv6 because they are carried over the same Layer 2 link and hence there can only be a single MTU value by definition.

Re: Speed HALFED again

chrcoluk — Wed, 09 Apr 2014 12:56:59 GMT

normally I would expect both to use the same, but for whatever reason plusnet's network now has different mtu sizes for ipv4 and ipv6.

Re: Speed HALFED again

AndyH — Wed, 09 Apr 2014 13:11:56 GMT

I don't think they do - I've tried that MTU testing site the Plusnet gateways/core routers (other servers in a v6 traceroute) and they all show a max MTU value of 1500 for v6 traffic.
I am wondering if there is a change somewhere else that might have caused this (our traffic passes through a lot of links before it even gets into PN's network).

Quote
One answer I want is why when I set the ipv6 mtu on windows its not overiding the higher mtu on the router.

Interesting question. What if you try this http://ccie-in-3-months.blogspot.co.uk/2011/06/debugging-ipv6-mtu-issues-in-windows.html ?
Another thing:
Is anyone here on ADSL and have they tried playing around with a 1500 MTU for v6?

Re: Speed HALFED again

jelv — Wed, 09 Apr 2014 14:05:08 GMT

The MTU on windows should not override the router - that is the point of path discovery. The MTU to be used is the LOWEST handled by all the devices between (and including) source and destination.