User comments on ISPs
>> Zen Internet

Print Thread

jelv
(knowledge is power) Tue 16-Mar-21 11:17:35

Horrendous packet loss

[link to this post]

I switched to Zen yesterday and while the connection seems OK the Broadband Quality Monitor is showing horrendous packet loss.
Graph from switchover day

The red 12am to 00:30 is after I swapped the router until the Zen connection came up. At first it looked fine, then bad loss until around 3am, then bad until around 7am. From then till midday it was bad and since then IPv4 is showing solid red.

This morning IPv6 has been enabled. IPv6 is showing bad packet loss while IPv4 is still solid red.

IPv6 16/03/2021
IPv4 16/03/2021

Is there something about Zen connections or the Fritz box router that means they don't prioritise pings so giving abnormal graphs?

I've tried pinging my router using PingTools on my phone with the WiFi off and am seeing roughly 90% packet loss on IPv4.

jelv

FTTC & Line rental: ZeN from March 2021

Previously: AAISP (November 2016 to March 2021) & Pulse8 line rental
Plusnet November 2001 to October 2016

prlzx
(experienced) Tue 16-Mar-21 12:26:45

Re: Horrendous packet loss

[re: jelv] [link to this post]

As I recall previous postings here suggest Fritzbox routers categorise the pattern of the pings as some kind of attack so drop lots of them, and that it still happens even when devices behind the router see the Internet connection as being not otherwise impacted.

I haven't checked recently but I expect at some lower rate of pings (if using a different monitoring system) it would not trigger that behaviour.

prlzx on Zen: FTTC (VDSL) at ~40Mbps / 10Mbps
with IP4/6 (no v6? - not true Internet)

RobertoS
(elder) Tue 16-Mar-21 12:41:06

Re: Horrendous packet loss

[re: jelv] [link to this post]

What do tracert stats to bbc.com look like?

My broadband basic info/help site - www.robertos.me.uk. Domains, sites and mail hosting - Tsohost & Ionos.
Connections: OnePlus 8 Pro max 165Mbps down, 24Mbps up on Three, and B311 4G, tbb tests normally 35-45Mpbs down, 65Mbps off-peak, 9-24 up.
========================
The EU’s multiple failures are due to a deeper malaise .... What malaise? The EU’s formidable immunity to the smallest amount of democracy. New Statesman Feb 2021.

jelv
(knowledge is power) Tue 16-Mar-21 13:46:41

Re: Horrendous packet loss

[re: RobertoS] [link to this post]

Absolutely fine - that's what had me confused as everything seemed OK using the connection.

Text

C:\Users\John>ping -4 -n 10 bbc.com
 Pinging bbc.com [151.101.64.81] with 32 bytes of data:
Reply from 151.101.64.81: bytes=32 time=13ms TTL=58Reply from 151.101.64.81: bytes=32 time=14ms TTL=58
Reply from 151.101.64.81: bytes=32 time=13ms TTL=58Reply from 151.101.64.81: bytes=32 time=13ms TTL=58
Reply from 151.101.64.81: bytes=32 time=13ms TTL=58Reply from 151.101.64.81: bytes=32 time=13ms TTL=58
Reply from 151.101.64.81: bytes=32 time=13ms TTL=58Reply from 151.101.64.81: bytes=32 time=13ms TTL=58
Reply from 151.101.64.81: bytes=32 time=13ms TTL=58Reply from 151.101.64.81: bytes=32 time=12ms TTL=58
 Ping statistics for 151.101.64.81:
    Packets: Sent = 10, Received = 10, Lost = 0 (0% loss),Approximate round trip times in milli-seconds:
    Minimum = 12ms, Maximum = 14ms, Average = 13ms 
 C:\Users\John>ping -n 10 bbc.com
 Pinging bbc.com [2a04:4e42::81] with 32 bytes of data:
Reply from 2a04:4e42::81: time=13msReply from 2a04:4e42::81: time=14ms
Reply from 2a04:4e42::81: time=12msReply from 2a04:4e42::81: time=13ms
Reply from 2a04:4e42::81: time=15msReply from 2a04:4e42::81: time=14ms
Reply from 2a04:4e42::81: time=14msReply from 2a04:4e42::81: time=13ms
Reply from 2a04:4e42::81: time=16msReply from 2a04:4e42::81: time=13ms
 Ping statistics for 2a04:4e42::81:
    Packets: Sent = 10, Received = 10, Lost = 0 (0% loss),Approximate round trip times in milli-seconds:
    Minimum = 12ms, Maximum = 16ms, Average = 13ms 
 C:\Users\John>pathping bbc.com
 Tracing route to bbc.com [2a04:4e42:200::81]
over a maximum of 30 hops:  0  xxxx.fritz.box [<removed>]
  1  fritz.box [<removed>]  2  lo-0.cor2.lond2.ptn.zen.net.uk [2a02:8010::103]
  3  ae-8.p1.ixn-lon.zen.net.uk [2a02:8010:0:800::2e]  4  2001:7f8:4::d361:1
  5  2a04:4e42:200::81 
Computing statistics for 125 seconds...            Source to Here   This Node/Link
Hop  RTT    Lost/Sent = Pct  Lost/Sent = Pct  Address  0                                           xxxx.fritz.box [<removed>]
                                0/ 100 =  0%   |  1    3ms     0/ 100 =  0%     0/ 100 =  0%  fritz.box [<removed>]
                                0/ 100 =  0%   |  2   12ms     0/ 100 =  0%     0/ 100 =  0%  lo-0.cor2.lond2.ptn.zen.net.uk [2a02:8010::103]
                                0/ 100 =  0%   |  3  ---     100/ 100 =100%   100/ 100 =100%  ae-8.p1.ixn-lon.zen.net.uk [2a02:8010:0:800::2e]
                                0/ 100 =  0%   |  4  ---     100/ 100 =100%   100/ 100 =100%  2001:7f8:4::d361:1
                                0/ 100 =  0%   |  5   13ms     0/ 100 =  0%     0/ 100 =  0%  2a04:4e42:200::81
 Trace complete.

jelv

FTTC & Line rental: ZeN from March 2021

Previously: AAISP (November 2016 to March 2021) & Pulse8 line rental
Plusnet November 2001 to October 2016

aidanh
(newbie) Tue 16-Mar-21 14:23:11

Re: Horrendous packet loss

[re: jelv] [link to this post]

Since you have IPv6 which is fully end-to-end (hurray for no NAT!) it would be interesting to see a traceroute to one of your client devices. I expect if the Fritzbox is doing clever prioritisation you'd see high ping and/or packet loss to the Fritzbox but this wouldn't carry forward to your end device (e.g the ping to your device at the end should be relatively low-latency and with no packet loss).

You can use ThinkBroadband's traceroute to do this as long as you connect to the website over IPv6 but you may need to re-configure any firewall on your device if it doesn't respond to ICMPv6 (Windows 10 stupidly defaults to blocking ICMPv6 even though doing this breaks IPv6 PMTU discovery):

https://www.thinkbroadband.com/tools/traceroute

jelv
(knowledge is power) Tue 16-Mar-21 16:25:31

Re: Horrendous packet loss: Line is fine, router drops pings

[re: aidanh] [link to this post]

After getting the advice that Fritz boxes throw a hissy fit if you try to monitor them by pinging, that's the thought I'd had and I've spent the afternoon configuring my NAS box, the router firewall rules, a new DNS AAAA record and setting up a new monitor.

IPv6 to NAS box

Looking good (so far).

jelv

FTTC & Line rental: ZeN from March 2021

Previously: AAISP (November 2016 to March 2021) & Pulse8 line rental
Plusnet November 2001 to October 2016

Edited by jelv (Tue 16-Mar-21 18:38:18)

prlzx
(experienced) Tue 16-Mar-21 17:29:47

Re: Horrendous packet loss

[re: jelv] [link to this post]

Great - I would agree that monitoring a permanently connected item behind the router (using the IPv6 firewall) is the way to go.

Regarding frequency I did 200 pings to my fritzbox router from an external VM at intervals of 3 seconds
and it only dropped 1 (0.5%).

prlzx on Zen: FTTC (VDSL) at ~40Mbps / 10Mbps
with IP4/6 (no v6? - not true Internet)

ukwiz
(fountain of knowledge) Wed 17-Mar-21 12:57:22

Re: Horrendous packet loss

[re: prlzx] [link to this post]

Sadly the Fritz reouters are broken. They can't cope with Zen running their ping tests and TBB at the same time.
My Broadband Ping

David

BT (poor) -> Zen (excellent) -> O2 (started well, went downhill -> IDNet (No complaints - but 100GB cap) -> Zen (gone downhill)

prlzx
(experienced) Wed 17-Mar-21 15:08:05

Re: Horrendous packet loss

[re: ukwiz] [link to this post]

As a blanket statement "broken" is pretty meaningless.
AVM have made a design choice around how to treat unsolicited WAN ICMP, and that happens not to envisage the TBB ping interval.

As noted this has no bearing on LAN and Internet connectivity of devices on the LAN, and a trivially longer ping interval is not impacted either.

The only other design limitation I have to deal with is the domain suffix being .fritz.box and not configurable.
I reported it to AVM as a way of finding out if a non-GUI way to change it, and they have no immediate plans to offer a configurable setting.
I have something else running internal DNS anyway for other reasons including remote office links.

On the other hand there are far worse routers still out there in terms of IPv6, firewall, NAT configuration or interaction with VPN connections so you take your pick.
This router was included with the subs but I could just as easily put back my previous router if this were really that "broken".

TBB have made their own design choice around the 1 ping per second and not user-configurable. I asked them about that, as I thought they could collect enough mass data at 1 ping per 6 seconds or 3 seconds
(which is still 100 per 5 mins aggregated as min/max/avg/loss to nearest 1%) but they have their reasons and it's their freely offered service, so that's ok too.

I work in ICT and you simply note the characteristics, choose your poison, deploy any targeted workarounds and move on.

prlzx on Zen: FTTC (VDSL) at ~40Mbps / 10Mbps
with IP4/6 (no v6? - not true Internet)

Edited by prlzx (Wed 17-Mar-21 15:22:06)

Print Thread

Jump to