It has come to my attention that Optus is throttling my P2P, sFTP, and FTP speed from 5 pm to 2 am exactly. I watched the logs on my machine and statistic graphs from the last two months, and the throttling happened at the exact same time +/- 1 minute.
I'm on the 50M plan and I got 6MB/s outside of the throttling period while only 500KB/s during the throttling period. I have stayed in front of my computer for entirely 2 months to watch the reads. I tried to connect with different peers from different countries, and I even tried to connect my workplace with a dedicated VPN, the result was better but it was still below 30M which is much lower than they promised.
It could not be caused by network congestion or problems at the peers' end, because I tried different peers, different ports and it happened at the exact same time over more than 60 days. I believe anyone with a proper education would know that's not coincident.
They send me a new modem last day and promised to fix the issue. I will see how it's going and keep this updated.
The Optus contract does enable them to throttle speeds of they feel it impacts on other users / the overall network performance.
Be interested in what eventuates
I scanned through the contract but did not find anything mentioned about speed or bandwidth. I think the relevant terms must be referred to other documents which may not be proposed by Optus. Therefore, I'm not sure if they are able to do that. Their staff promised to get my speed back to 30M though.
Update: I received the new modem yesterday and installed it. I connected the machine to the modem with a cable. The speed was good at around 4MB/s last night.
Sadly, the throttling issue recurred tonight. It stays at 500KB/s tonight. I will keep reflecting the issue to Optus customer service.
After doing some researches, I learned the following facts.
The reason they throttle p2p traffic is that the bandwidth they bought from NBN versus the bandwidth you bought from them was around 1:800. That means they will make efforts to prevent you from 'affecting' other users.
The throttling is not typically done on their router, so it won't work by plugging your own router to the NBN box.
It is the NBN box that does the throttling logic. There is a TR069 connection which allows it to get throttling orders from ISP based on real-time usage statistics. Once the ISP think there is too much traffic than they can handle, they would initiate a throttling request to the NBN box, and the request will be executed every hour. That's why I always found throttling happening at exact time points.
The reason I got a faster speed sometimes after a rebooting is because I was assigned a new id and hasn't been assigned with a throttling request.
Solutions are to get root access of the NBN box (requires some tech), get a customized NBN box (need to know your ids and all other info) from somewhere else, or use a VPN.
Hope this will help people suffering from the same issue.