When we talk about travel, we often say trains are better than other forms of transport due to being able to work. If you rely on Internet connectivity however, this is optimistic to say the least.
On a receipt trip to Cardiff, we found the Wi-Fi service from GWR to be almost unusable due its instability. Not only is it slow, the jitter (variation in latency) is through the roof.
On-board inter-city train Wi-Fi can be challenging as you’re connecting a fast moving train. This could be done via trackside infrastructure, the mobile network or using satellites. We know the flying world is talking about Starlink everywhere replacing air-to-ground systems with fast on-board connectivity but in the mean time our trains at least, are stuck on some very outdated slow, unreliable technology.
We saw issues both on the trip to Wales, but also back to London so it’s not just a one off incident, and it’s been the same for years. Ignoring the connectivity issued in tunnels (although tunnels have coverage on the Underground in London, this is quite expensive and won’t work via satellite), we found the stability of the connection was poor, even whilst sitting still on the train at the platform in Bristol Parkway station.
Stability — Latency, Jitter and Packet loss
Here’s an example of what the connection looks like pinging one of our systems once a second. The minimum latency of 34ms is very respectable; even 50-75ms may not necessarily be an issue, but we also saw many packets exceed 400ms, even up to 782ms, almost a second. This not only destroys usability of any ‘interactive’ application, it means every single request you make for a web page stacks up, requesting a page, some scripts/images, etc. Any interactive fields would need to be requested separately which depending on the application could make the experience quite bad.
64 bytes from 80.249.99.164: icmp_seq=1250 ttl=55 time=33.918 ms
64 bytes from 80.249.99.164: icmp_seq=1251 ttl=55 time=46.201 ms
64 bytes from 80.249.99.164: icmp_seq=1252 ttl=55 time=282.214 ms
64 bytes from 80.249.99.164: icmp_seq=1253 ttl=55 time=391.482 ms
64 bytes from 80.249.99.164: icmp_seq=1254 ttl=55 time=293.326 ms
64 bytes from 80.249.99.164: icmp_seq=1255 ttl=55 time=231.952 ms
64 bytes from 80.249.99.164: icmp_seq=1256 ttl=55 time=73.974 ms
64 bytes from 80.249.99.164: icmp_seq=1257 ttl=55 time=43.986 ms
64 bytes from 80.249.99.164: icmp_seq=1258 ttl=55 time=44.461 ms
64 bytes from 80.249.99.164: icmp_seq=1259 ttl=55 time=104.107 ms
64 bytes from 80.249.99.164: icmp_seq=1260 ttl=55 time=371.060 ms
64 bytes from 80.249.99.164: icmp_seq=1261 ttl=55 time=555.779 ms
64 bytes from 80.249.99.164: icmp_seq=1262 ttl=55 time=579.059 ms
64 bytes from 80.249.99.164: icmp_seq=1263 ttl=55 time=497.427 ms
64 bytes from 80.249.99.164: icmp_seq=1264 ttl=55 time=415.247 ms
64 bytes from 80.249.99.164: icmp_seq=1265 ttl=55 time=434.218 ms
64 bytes from 80.249.99.164: icmp_seq=1266 ttl=55 time=594.134 ms
64 bytes from 80.249.99.164: icmp_seq=1267 ttl=55 time=782.471 ms
64 bytes from 80.249.99.164: icmp_seq=1268 ttl=55 time=424.761 ms
64 bytes from 80.249.99.164: icmp_seq=1269 ttl=55 time=273.099 ms
64 bytes from 80.249.99.164: icmp_seq=1270 ttl=55 time=99.885 ms
64 bytes from 80.249.99.164: icmp_seq=1271 ttl=55 time=55.001 ms
64 bytes from 80.249.99.164: icmp_seq=1272 ttl=55 time=51.047 ms
64 bytes from 80.249.99.164: icmp_seq=1273 ttl=55 time=55.879 ms
Not only that, we also saw random periods of packet loss, where a packet timed out (possibly due to taking several seconds before the command gives up.)
This may not affect sending/receiving e-mail or reading news from an app, but if you want to browse the Internet or do anything interactive on the web, it becomes snail’s pace.
Speed
The other factor in doing anything online is speed. The service was barely able to deliver 1Mbps both upstream and downstream. This is about double the speed of an entry-level broadband connection 25 years ago, 13% of the maximum speed of an ADSL2+ connection over an all-copper line from the telephone exchange (up to 8 meg) and anywhere from 1.3% upwards of what we called (part) fibre broadband, and 0.1% of a Gigabit connection over 90% of UK homes can how get.
Whilst there’s a difference between mobile connectivity, especially when in motion, and what you expect at home, what makes this all the worse is 4G connectivity on a mobile phone was able to deliver 10-25x that speed, although this varied, but even the slowest results were more than double the on-board Wi-Fi.
The provider of the on-board Wi-Fi service is Nomad Digital routed via Iomart. Tests using another popular speed test website also showed the slow speeds (on multiple servers):
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Very disappointing! Seems like the WiFi is provided as an afterthought
I caught one of the GWR improved wifi trial trains, and the difference was incredible. Rock solid consistent performance throughout the journey: https://www.bbc.co.uk/news/articles/cqjwkdez71ro
Wow this looks great! If only I could book a train which had this..
I do like time to read but I’m time short and needed to work on something.
I think there is genuinely one train with the “experimental” good wifi. (iirc was meant to run until December or January but they just kept it).
baffling as to how it hasn’t been deemed a success considering how much better it is.
perhaps cost…
LNER is no different and the same system appears to have transferred onto the new IEP trains upon their introduction despite an opportunity for upgraded equipment. Obviously, a full train does cause a lot of router congestion but mobile signals are a lot more stable and faster at the moment,
We had new trains introduced on my local line (Thameslink) a few years ago and were told they would have WiFi. By my estimate, only about 1 in 5 of their trains that I use actually provide WiFi at all (they have the WiFi symbol on the doors when they do), so you’re lucky if you get any coverage, good or bad.
Currently on a CrossCountry train the wifi is EVEN slower. To add insult to injury, it’s one of those trains where it’s nearly impossible to get mobile signal onboard!