Surely this is throttling?

One of the reasons I switched to Zen was for the gig network and their claims of absolutely zero traffic shaping/throttling.

I even went as far as to ask about file sharing/torrents and they claimed nothing was throttled.

However, throttling is the only thing I can think of that is accounting for this behaviour.

Run a speed test and down/up speeds and 800+mbps
Launch torrent client, still the same speeds
However, the moment any torrent becomes active at any speed, down/up drops to 80-100mbps

I capped down/up speeds in the client to 10kbps and the same behaviour. As soon as any torrent is actively seeding or downloading, I get a significant connection speed drop.

I moved all file sharing activity to a different PC on the network, and the same issue followed it.

Besides throttling, anything else I might have missed in router settings maybe? Ports are set and confirmed as open.

TIA

Your terminology is rather screwed up, and your speed problems could be associated with your possible confusion.

First, you appear to be on a 900Mbps FTTP connection. Three points about that, and one in particular is vitally important. Even though all initially seem pedantic.

First on FTTP your connection speed is fixed. It cannot change. You mean throughput speeds.

Second, and will become important later, note the capital M and small b. Mbps is Megabits per second; mbps is millibits per second. M for Million, m for one millionth.

The "b" is the one that matters most. Small b is bits. Capital "B" is bytes. One byte contains 8 bits.

The speeds up and down are measured in bits per second when looking at connection and speed test speeds. But when downloading or uploading we are looking at the speed a file is transmitted at, and file sizes (for most of us these days and certainly in Windows/MSDOS) are measured in Bytes.

The speeds shown by file transfer programs are almost alway reported in MegaBytes per second, enabling us to easily see/estimate the time to completion.

If you divide your 900Mbps by 8 you get 111MBps. Then allowing for overheads and other influences your throughput speed will be a bit lower.

I believe your "However, the moment any torrent becomes active at any speed, down/up drops to 80-100mbps" is actually showing onscreen as 80-100MBps.

Your 10kbps makes no sense to me. Ten kilobits per second, (confusingly note that capitalisation or not of the k in this instance always refers to kilo = one thousand) is like taking part in an F1 race on a kiddie's tricycle.

I hope that's resolves your speed problems.

You said you've limited the speed of your torrents so as to stop them saturating the bandwidth, but have you also limited the number of connections the torrent client can make?

Torrents typically create a large number of connections per torrent, this might be causing your router to become swamped and create the slowdowns you are experiencing.

Try in your torrent program, limiting the number of connections per torrent and the maximum number of connections globally. As a starting point, choose say 200 maximum connections globally and say 100 per torrent and see what happens and if it's still the same then halve those numbers. Make sure you do still cap your upload and download bandwidth for the torrent program too. Cap the bandwidth at say 100meg down and 20 meg up. See if you can see the status of your router too while you have torrents going, i'm not sure if you can see how much RAM & CPU is being used in the router itself, but if all the routers resources are being used by a huge number of connections, then that might be your problem.

sorry, yes... school boy error on the capitalisation.

Yeah, I have tried exactly that with no change.

When i first switched to Zen, I was getting approx 70-80MB/s downloading.

That only lasted a short while and now it's pretty much sits at 10MB/s

SSD or HDD?
What torrent client are you using?

I have tried two different systems.

Both running the OS on an SSD and the files are being saved to an additional internal SSHD.

Have also tried saving the files directly to the system SSD.

Running utorrent, but have tested with Vuse, deluge and qb and all experienced the same.

How many simultaneous connections?

It may be worth connecting your machine directly to the ONT to rule out the router.

I would also try booting into a live Linux environment and running a torrent client there to rule out a software issue.

After all that, turns out the issue was with CityFibre.

A while back they migrated everyone to a new VLAN.

Low and behold, i'd been left behind on the old one.

Back up to full speed, happy days!

Good. There isn't really any value in throttling Bittorrent now. Most people use legit streaming and downloading services for content which is pulled from content delivery networks now the content is more available under better terms.

It's thankfully a while since torrent usage was a grimly high proportion of traffic and a target for shaping. Same for Usenet. Another bonus of increased legit usage it drowns out the dubious protocols. The hardware to do it is expensive enough to give pause, too.

Network neutrality legislation left only caps or indiscriminate throttling based on usage.

Will see what happens in the future! ISPs are fine with the odd user with a dedicated machine to download and seed torrents at a gigabit however the smaller ones without big customer bases to dilute the few and actually CityFibre might need to take some measures to address them.