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I know my new ISP is enforcing a lot of different limitations. They refuse to say what are the limits.

To determine bandwidth I can use sites like (BTW it shows me ~15% of what I am promised to have (sic!))

I noticed that there is probably also a limit on number of opened connections. To determine it, I picked a random torrent with more than 10 000 seeders. I am able to connect up to 50. Torrent trick is easy, but it is not a perfect solution, because torrent connections are probably classified to some P2P pool with different limits.

The question is: what are another ways to determine maximum number of opened connections silently enforced by my ISP?

I Ask for ideas. I am a programmer and I use Linux. I can write some shell script, python or c code, or whatever. It's not a problem, but who to connect to not look like some DOS attacker. Do you know some host pools I can open a lot (>100?) of connections to? Any other ideas?

Thank you

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migrated from Feb 8 '13 at 5:46

This question came from our site for system and network administrators.

And yet torrent is not a good example, as most bittorrent clients enforce a limit of 50 peers per torrent by default (adjustable). – Martino Dino Feb 7 '13 at 21:00
This page from EFF has a table of "ISP Testing software". Mainly this deals with forged RSTs, etc, but may be helpful: – Cory J Feb 7 '13 at 21:05
@MartinoDino: I am aware of my torrent client connection limits. I set it to 200 and still get only 50. Thanks anyway for pointing that out. – Michał Šrajer Feb 7 '13 at 21:11
up vote 3 down vote accepted

M-Lab aka measurementlab was created for that purpose, you can use their tools to check if your provider enforces limits and what they are.

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I will give it a try. Thank you. – Michał Šrajer Feb 7 '13 at 21:09

If your ISP cannot or will not disclose limits, how do they expect you to comply? You might consider changing ISPs.

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I would love to change ISP to ANY other, but they cut the cable of the only competitor. I have no choice. :-/ Bladdy bastards! (I apologies for my language) – Michał Šrajer Feb 7 '13 at 22:13

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