Explore London, UK to Johannesburg, South Africa ICMP RTT, jitter, packet loss and fiber latency limits on the AS203314 network.

🇬🇧 London, UK (LON) → 🇿🇦 Johannesburg, South Africa (JNB)

Measurement round: 2026-08-16T04:07:28Z.

London to Johannesburg averaged 179.6 ms, compared with a 88.52 ms city-centre fiber reference. The difference cannot be assigned to a particular cable or carrier from RTT alone.

Standard deviation was 5.96 ms, or 3.3% of the average. This describes variation within the sample without identifying its cause.

Latency Summary

Metric	Value
RTT	179.6 ms
Jitter	4.3 ms
Packet Loss	0%
Standard Fiber Floor	88.52 ms
Fiber Efficiency	49.3%
Latency Tier	Fair
Source Region	Europe
Destination Region	Africa

Ping Measurement Series

50 ICMP echo probes were recorded in this round. Individual replies and their distribution are shown below.

Ping series: LON → JNB

50 ICMP echo samples at 100 ms intervals · round 2026-08-16T04:07:28Z · avg 179.6 ± 0.84 ms (SE)

Sample distribution: box = interquartile range (175.6–181.5 ms), median 178.5 ms · whiskers = min–max · diamond = round average · each dot is one measured sample.

How to read this chart

The shaded band spans the measured minimum to maximum RTT of all samples collected up to that point, and the thin line traces the running average. The final position therefore matches the round statistics exactly. The band only widens when a new extreme sample arrives.

The dashed line is the round average, and the shaded band at the bottom is the theoretical fiber-optic floor (88.5 ms) for this route.

Full 50-sample dataset

Seq	Offset (ms)	RTT (ms)
1	0	203.66
2	100	183.26
3	200	190.30
4	300	185.09
5	400	182.78
6	500	175.67
7	600	176.09
8	700	179.12
9	800	178.30
10	900	176.56
11	1000	184.35
12	1100	178.95
13	1200	179.18
14	1300	177.62
15	1400	174.42
16	1500	175.05
17	1600	172.46
18	1700	186.53
19	1800	176.49
20	1900	181.50
21	2000	175.64
22	2100	173.03
23	2200	180.86
24	2300	177.15
25	2400	179.78
26	2500	179.46
27	2600	180.10
28	2700	175.63
29	2800	176.53
30	2900	180.46
31	3000	180.96
32	3100	175.87
33	3200	190.48
34	3300	189.95
35	3400	186.53
36	3500	178.74
37	3600	174.02
38	3700	173.24
39	3800	174.98
40	3900	172.64
41	4000	171.60
42	4100	173.80
43	4200	173.55
44	4300	177.04
45	4400	176.14
46	4500	181.35
47	4600	188.13
48	4700	180.37
49	4800	178.23
50	4900	186.36

Download This Route's Data

Download the probe round as CSV, JSON or YAML under CC BY 4.0. Citation details include the route and round timestamp.

CSV JSON YAML Full dataset

Theoretical Fiber Latency

The propagation model uses public city-centre coordinates from GeoNames: London (51.50853, -0.12574) and Johannesburg (-26.20227, 28.04363). These are not facility coordinates or a surveyed cable path.

Physical Reference	Value
WGS-84 geodesic distance	9,039.3 km
Vacuum RTT floor	60.3 ms
Standard fiber RTT floor ( $n_g=1.4679$ )	88.52 ms
Low-latency fiber material floor	88.16 ms
Engineering floor (5% path allowance)	92.96 ms
Research 1.33× mapped-fiber reference	117.73 ms
Estimated unamplified path loss	1898.3 dB
Transparent optical spans / inline amplifiers	119 / 118
Published RTT inflation over fiber floor	2.03×

The span count assumes 80 km optical spans. Attenuation is a power-loss term, not a propagation delay. See the model assumptions and equations.

Stability & Trend

Statistics from the same 50 replies. They describe this probe round, not continuous historical monitoring.

Round Statistic	Value
Minimum RTT	171.6 ms
Average RTT	179.6 ms
Maximum RTT	203.66 ms
Standard deviation	5.96 ms
Stdev / average	3.3%

Estimated RTT trend

Modeled comparison, not historical probe measurements.

Average: 179.7 ms
Minimum: 177.5 ms
Maximum: 181.3 ms
Average loss: 0.02%

Route Context

Departure PoP: London (LON)
Destination PoP: Johannesburg (JNB)
Region overview: Europe → Africa
Full global matrix: Backbone Latency Matrix
Physical methodology: Theoretical Fiber Latency

Reverse direction

Johannesburg to London latency and RTT: 158 ms

Fastest routes departing London (LON)

London to Amsterdam latency and RTT: 5.2 ms
London to Paris latency and RTT: 6.4 ms
London to Frankfurt latency and RTT: 13.6 ms
London to Berlin latency and RTT: 16.2 ms
London to Marseille latency and RTT: 17.9 ms

Fastest routes arriving at Johannesburg (JNB)

Amsterdam to Johannesburg latency and RTT: 171.9 ms
Berlin to Johannesburg latency and RTT: 172.1 ms
Paris to Johannesburg latency and RTT: 180.9 ms
Frankfurt to Johannesburg latency and RTT: 188.4 ms
Marseille to Johannesburg latency and RTT: 198.5 ms

Same corridor (Europe → Africa)

Moscow to Johannesburg latency and RTT: 201.9 ms

About This Measurement

These ICMP measurements cover the two backbone endpoints. Access networks, routing policy and load can change an end user's result. A probe round is not an SLA.

The underlying replies are available under CC BY 4.0 in the Hats Network latency dataset. Per-pair files are available at /opendata/latency/latest/pairs/lon-jnb.pings.{csv,json,yaml}. Cite the route, round timestamp and dataset version. Example: "Hats Network latency dataset, London → Johannesburg round 2026-08-16T04:07:28Z, CC BY 4.0".

Round published August 16, 2026. See the full interactive latency matrix or browse more city-pair routes.

London, UK → Johannesburg, South Africa RTT