UPC High Packet Loss

aphex™ · 19-04-2014 09:42AM #1

I'm seeing huge packet loss of up to 50% on the UPC network. The packet loss is occurring after leaving my router.

Is anybody having similar issues?

See attachments.

I am using Pingplotter free and Nice Trace on the ipad to look at the pings to various hosts.

aphex™ · 19-04-2014 09:50AM

Also note the packet going through Austria before they hit boards through the INEX! :eek:

ED E · 19-04-2014 09:57AM

Same, dropping traffic at the transit in Wexford before heading to holland.

aphex™ · 19-04-2014 05:09PM

Yeah I'm in D16 myself.
Could we have some other reports? Preferably with screenshots/ pasted data.

Alun · 19-04-2014 05:43PM

aphex™ wrote: »

Also note the packet going through Austria before they hit boards through the INEX! :eek:

I wouldn't be to sure of that .. UPC Ireland use a block of addresses officially registered to UPC Austria that are being reused. Your router will occasionally pick one of them up which causes all kinds of hassle with sites that do IP Geolocation.

ED E · 19-04-2014 06:18PM

ICMP unfortunately isnt reliable for testing as its the firs thing that gets dropped but Ive booted pingplotter back up. Ill post a few hours worth later.

nickhilliard · 20-04-2014 08:40AM

aphex™ wrote: »

I'm seeing huge packet loss of up to 50% on the UPC network. The packet loss is occurring after leaving my router.

the traceroutes all look fine to me and do not indicate any problem on the UPC network. You can tell this because all of the other IP addresses after this link are showing 0% packet loss.

The reason that 80.111.12.1 is dropping 50%+ of your traceroute packets is because these packets are handled by the management controller on the device, and traffic which hits the management controller is carefully policed to ensure that it doesn't swamp the controller CPU with junk. It would be normal on a box like this to restrict ping and traceroute replies to a tiny amount.

Traffic travelling through a router (or CMTS in this instance) is normally forwarded by special purpose hardware which can shift data at high speeds. You can see clearly in the traceroute results that all the through-traffic is getting through, and that none of it is dropped.

If you want more technical details on how this works and why, run a web search for "rfc6192" or "control plane policing".

Nick

ED E · 20-04-2014 02:51PM

Reasonably clean overnight. But you can see two periods when the link goes as close to dead as possible.

UPC High Packet Loss

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