FTTH GPON Latency and throughput in european residential home networks

a_gpon_fiber_latency_ftth.md

Summary

Expect the following latencies to the "first hop":

ADSL         19 ms (depends on interleaving times)
VDSL50       24 ms (without Vectoring, no detail data in this report)
VDSL50        4 ms (with Vectoring)
GPON Fiber  1.5 ms (nearly the same in France & Germany)
COAX Docsis 7.5 ms (line is not stable unfortunately)

Germany

VDSL50 Vector Line

Provided by Telekom Deutschland. VDSL2 17a G.Vector (ITU G.993.5). 50 Mbit/s DOWN, 10 Mbit/s up. Line was synchronised for 66 days. CPE is Fritzbox 7390. SNR 11/18 db, attenuation 12/17 db.

HOST: ubuntu                      Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- p3e9bxxxx.dip0.t-ipconnec  0.0% 10000    4.5   4.3   1.0 101.3   6.6
        fritz.box                        
  2.|-- p3e9xxxx6.dip0.t-ipconnec  0.0% 10000    4.5   4.3   3.7  97.1   6.1
  3.|-- 217.0.2xx.x                0.0% 10000   11.5  15.5  10.8 383.4  32.7
  4.|-- 217.243.177.179            0.0% 10000   11.0  10.8  10.5  51.8   2.7
  5.|-- fra1.cc1.as48314.net       0.0% 10000   32.1  38.9  12.8 605.1  26.5
  6.|-- lg.ip-projects.de          0.0% 10000   11.4  10.8  10.5  35.6   0.5

ADSL Line

Provided by Telekom Deutschland. ADSL 2+ (ITU G.992.5) Annex J . 5 Mbit/s DOWN, 1.4 Mbit/s UP. Interleaving Latency is (8+8) ms. CPE is Fritzbox 7530, SNR 10/6db, Attenuation 33/18 db. When the line synchronises with higher speed, it is not stable.

Interleaving makes up 16ms of the best-case first-hop latency of 19.9 ms.

Start: 2023-03-06T02:04:02+0100
HOST: debian-                                                      Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- 192.168.3.254                                                79.3%  7200    2.0   0.9   0.6   2.8   0.4
  2.|-- p3e9xxxxx.dip0.t-ipconnect.de (62.155.2xx.x)                  0.0%  7200   36.5  21.3  19.9  99.5   6.3
  3.|-- f-ed11  .F.DE.NET.DTAG.DE (217.5.6x.xxx)                      0.0%  7200   22.4  21.6  20.9  59.1   2.0
  4.|-- 87.128.239.xxx                                                0.1%  7200   22.3  22.1  21.3  88.9   1.5
  5.|-- de-fra01e-rb01-b2b-umb-de-be-1050.aorta.net (84.116.191.110)  0.0%  7200   23.5  21.5  20.6  54.7   1.4
  6.|-- ip-005-147-248-006.um06.pools.vodafone-ip.de (5.147.248.6)    0.0%  7200   22.2  22.6  21.2 126.2   5.3
  7.|-- ae-2.dc1.r206.fra0.as12312.net (62.27.97.82)                  0.0%  7200   23.1  22.1  21.2 110.1   3.0
  8.|-- ae-0.sw10.r001.fra0.as12312.net (62.27.99.234)                0.0%  7200   28.0  25.8  21.0 133.4   6.0
  9.|-- 212.172.19.102                                                0.0%  7200   25.0  23.0  21.8 131.6   3.1
 10.|-- sbc10.pbx.easybell.de (212.172.97.120)                        0.0%  7200   22.1  21.0  20.6  94.7   1.4

FTTH GPON

Provided by Telekom Deutschland. This is a 2.5 Gbit/s DOWN, 1.25 Gbit/s UP shared GPON. The Fiber terminates in our rack cabinet. CPE is a "Telekom Glasfaser Modem 2", behind is a Fritzbox 7530 AX which does the PPoE Dial-In.

Interesting is the first-hop latency which is 1.4ms in the best-case. I don't have any explanationf or the packet loss.

Start: 2023-03-06T02:04:02+0100                                     
HOST: debian-                                                      Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- 192.168.3.252                                                 0.0%  7200    0.5   0.5   0.4  12.3   0.2
  2.|-- p3e9xxxxx.dip0.t-ipconnect.de (62.155.2xx.x)                  0.0%  7200    2.2   2.2   1.4  81.5   6.5
  3.|-- f-ed11  .F.DE.NET.DTAG.DE (217.5.6x.xxx)                      0.0%  7200    4.3   4.2   3.6  33.8   1.4
  4.|-- 87.128.239.xxx                                                0.2%  7200    4.1   4.0   3.6  14.1   0.4
  5.|-- de-fra01e-rb01-b2b-umb-de-be-1050.aorta.net (84.116.191.110)  0.0%  7200    4.0   4.0   3.2  10.1   0.4
  6.|-- ip-005-147-248-006.um06.pools.vodafone-ip.de (5.147.248.6)    0.0%  7200    3.6   3.4   2.8  51.7   4.9
  7.|-- ae-2.dc1.r206.fra0.as12312.net (62.27.97.82)                  0.0%  7200    4.6   3.3   2.9  40.9   2.4
  8.|-- ae-0.sw10.r001.fra0.as12312.net (62.27.99.234)                0.0%  7200    5.2   7.0   3.4  93.0   5.5
  9.|-- 212.172.19.102                                                0.0%  7200    6.1   4.5   3.9 104.7   2.7
 10.|-- sbc10.pbx.easybell.de (212.172.97.120)                        0.0%  7200    3.9   3.7   3.2   9.4   0.3

ADSL to GPON

Both the ADSL Line and the FFTH line terminate in the same building and seem to use the same POP. The first-hop looks to be the same. So I did some mutual pings.

This underlines the first-hop response time of ≈ 1.5ms for the Fiber and ≈19.8 for ADSL. I don't have any explanation for the packet loss.

Start: 2023-03-06T02:04:02+0100
HOST: debian-                                       Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- 192.168.3.252                                 99.9%  7200    0.6   0.8   0.6   0.9   0.1
  2.|-- "hop1"   .dip0.t-ipconnect.de (62.155.xyz.a)   0.0%  7200    2.1   2.0   1.5 102.4   6.6
  3.|-- p5b2     .dip0.t-ipconnect.de (91.47.def.ghi)  4.5%  7200   21.7  21.4  20.7 118.1   1.7

HOST: debian-                                       Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- 192.168.3.254                                 18.8%  7200    1.1   0.6   0.6   5.3   0.6
  2.|-- "hop1"   .dip0.t-ipconnect.de (62.155.xyz.a)   0.0%  7200   20.6  21.5  19.8 103.3   7.2
  3.|-- p5b3     .dip0.t-ipconnect.de (91.47.klm.opq)  2.4%  7200   22.1  21.1  20.4  86.1   1.4

Cable Modem

Provided by Vodafone. CPE is a Fritzbox 6591 Cable . Downstream uses DOCSIS 3.0 only, Upstream uses 1 Channel of DOCSIS 3.1 and 4 Channels of DOCSIS 3.0. This line is in the same building as the GPON Fiber line.

Unfortunately, this connection needs a reboot of the modem every ≈ 3 weeks, as the upstream direction will loose the 64 QAM Modulation and Fall back do 16 QAM. The line seems to be disturbed in the rf spectrum, but the customer service won't do anything about it.

The modem gets a static IPv4 without CGNAT. I consider the first-hop latency to be 7.4 ms

Start: 2023-03-06T02:04:02+0100
HOST: debian-                                                      Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- 192.168.3.253                                                 0.0%  7200    0.9   0.4   0.3   8.0   0.6
  2.|-- ???                                                          100.0  7200    0.0   0.0   0.0   0.0   0.0
  3.|-- de-fra04a-rd0.fra.unity-media.net (81.210.1xx.xx)             0.0%  7200    9.2   8.9   7.4  59.5   3.8
  4.|-- 145.253.48.220                                                0.0%  7200   11.3   9.5   7.5  51.4   3.5
  5.|-- ???                                                          100.0  7200    0.0   0.0   0.0   0.0   0.0
  6.|-- ip-005-147-248-006.um06.pools.vodafone-ip.de (5.147.248.6)    0.0%  7200    9.1   8.9   5.4  66.3   5.3
  7.|-- ae-2.dc2.r001.fra0.as12312.net (62.27.97.90)                  0.0%  7200    8.9   8.1   6.7  56.1   2.9
  8.|-- ae-1.sw10.r001.fra0.as12312.net (62.27.99.254)                0.0%  7200    9.8  12.6   7.9  75.6   5.6
  9.|-- 212.172.19.102                                                0.0%  7200   10.8   8.9   7.7  55.9   2.4
 10.|-- sbc10.pbx.easybell.de (212.172.97.120)                        0.0%  7200    8.7   6.8   6.6  26.8   1.1

France

Test location is a single family home in département 38.

The ISP is Orange (ex. France Télécom).

The CPE is a orange livebox 5. The monthly package includes 2 Gbit/s DOWN , 600Mbit/s UP with no data cap and is 50€ (2022).

Speedtests

The speed tests needed multiple devices, as there are only 1 Gbit/s Ethernet Ports on the router. We were able to saturate the 2 Gbit/s DOWN , 600Mbit/s UP simultaneously (measured with iperf over 120 seconds).

Latency

Measured with mtr . Started roughly after midnight and lasted for 9000 seconds, i.e. the least busy time of the day. The router does dual-stack. Measurement PC is attached via cable. WIFI disabled.

The first-hop latency is 1.2ms in best-case ipv4. What I find interesting is that ipv6 seems to be consistently slower, even the best-case first-hop latency for ipv6 is 1.9ms and thus 0.7ms slower than on ipv4.

End-to-end however, the average is nearly the same, and stdDev is lower for ipv6.

Using an WAN Latency Estimator gives the lower limit at 9.6 ms (600km), so roughly 2/3 of the latency a attributable to the link itself, and 1/3 to processing and devices.

ipv4

Start: 2022-12-26T00:18:23+0100
HOST:              xxx.home       Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- livebox.home               0.0%  9000    0.6   0.5   0.4 124.9   2.7
  2.|-- 80.10.232.2xx              0.1%  9000    2.2   2.2   1.2  54.7   2.9
  3.|-- 80.12.193.2xx              1.1%  9000    2.6   2.2   1.3 119.1   4.0
  4.|-- 80.12.193.218              0.0%  9000    2.7   2.7   1.8  94.6   6.7
  5.|-- ae43-0.nilyo201.rbci.oran  0.0%  9000    4.8   4.7   3.9  84.5   3.6
  6.|-- 81.253.184.114             0.0%  9000   14.7  15.4  13.6 113.0   8.7
  7.|-- 81.52.186.188              0.0%  9000   14.4  14.5  13.6 156.8   4.6
  8.|-- fra1.cc1.as48314.net       0.0%  9000   23.9  30.0  14.7 341.7  21.2
  9.|-- lg.ip-projects.de          0.0%  9000   15.0  14.7  13.8 249.4   4.2

ipv6

Start: 2022-12-26T00:18:32+0100
HOST: xx.home                     Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- livebox.home              89.7%  9000    0.8   0.8   0.6  25.3   1.7
  2.|-- 2a01cbxxxxxxxxeeeeeeeffff  0.0%  9000    2.9   2.7   1.9  96.9   3.6
  3.|-- 2a01:cfc4:0:a00::b         0.0%  9000    5.5   5.3   4.2 111.3   7.4
  4.|-- ae101-0.ffttr7.frankfurt.  0.0%  9000   21.5  15.2  13.9 259.0   8.4
  5.|-- ???                       100.0  9000    0.0   0.0   0.0   0.0   0.0
  6.|-- fra1.cc1.as48314.net       0.0%  9000   21.0  22.1  14.6 284.3  18.0
  7.|-- lg.ip-projects.de          0.0%  9000   15.2  14.8  13.8 115.4   3.7

Hey I would like to know how you managed to get ADSL working??
I thought that in Germany (Telekom) only provides FTTx and VDSL with vectoring enabled...
I really miss the old ADSL feelings for gaming with Fast path (no interleaving).
If you could share the config to get ADSL working or reducing interleaving on VDSL, would be great

Hello, there is nothing you can influence. In my examples above, the line length decided what is possible. The ADSL Line is about 2km long, and my best VDSL Vectoring is only about 300m. Less interference on the line will lead to better signal quality and less interleaving. Is your inhouse cabling correct? I do not miss ADSL, as the Vectoring line has lower latency than ADSL.

Oh ok I only have 108m to the DSLAM so only VDSL available... So many years ago I was a moderate CS 1.6 player at ADSL 1600 kbps with Fast path. Hitreg was fast and ping is king. Then they shut it off and transfered to VDSL... Tryed 16mbits, 50mbits, 100mbits and 250mbits on the same house/line than the previous ADSL and had to retire my esports "career"... Also tested other types of router... Always feeled hat I am a good amount of milliseconds behind. This was 2012/2013 if I remember correctly... Then after I moved to another location (also only VDSL available) I changed all "old" copper wire in the house to new one, also the TAE, all down to the APL. So my inhouse is good and have less resistance than before. But also the feeling is really bad. Even a router that makes my line in every circumstance jitter free due SQM feels like a disadvantage. For sure a checked all parameters like packet loss etc. Even in the good old games which have no lag- compensation (CS1.6) I can't react to enemy's and always got first shoot first dying... 8ms ping feels like 150ms to Fast path. Sure I can manipulate lag compensation with clumsy but this is forbidden in any competitive environment.

Then the problem is very certainly not on your DSL Line. The VDSL Latency ( no interleaving ) is << ADSL . You could argue about your ISPs peering policies and from my experience 1und1 if they do the peering themselves is much better than DTAG.

I personally think that Interleaving is the problem. After a Line Reset from ISP, it feels great for 1-2 days (like ADSL) then it is worse than before. After I got sick of all the tuning bullshit and pseudo-tweaks for networking, I switched to console gaming to get the same environment than others with console. So the only tweaks I can try are on router base. There I tested also several things like Draytek Modem, Fritzbox etc.
Sadly no ISP allow to disable interleaving -.-

Your modem should report if it uses interleaving. This is not something you must guess about.