Restricting / stopping streamining

[#1]

Hi,
We have a business broadband account as we are a club.  We don't have a lot of broadband usage in normal circumstances, so are on a limited plan, as most of the time it is just uploading some stuff to teh website via FTP and emails.
However, when some people start streaming games or videos (I assume) then it can eat our allowance. E.g. yesterday  someone managed to eat 8.5gb  in 8 hours, which is more than our normal monthly usage.
Is there some way I can limit or stop  this sort of excessive usage. There is no legitimate reason for members to be streaming films or games.  e.g are there some common port ranges to block, or something else that could limit those port ranges
Thanks

[#2]

Hi Alan,
A warm welcome to the forums.
Restricting access to discrete Internet services is a tricky task if you do not know exactly what you are doing.  A simpler approach might be to consider what you want to allow and then set very tight allow restrictions.
A simpler approach might be to inhibit all access except for approved users.
There is a sizeable range of ports used for the bandwidth hungry applications, where as there are quite a restricted number of ports used for FTP, web and email access.  Potentially you could close all ports and allow only those required for ftp, web and email.  However some services stream over http (web ports).
Implementation needs more knowledge than I posess, however the first step us to work out what you want to allow different profiles of users to do.  Than will define the technical requirements.
Alternatively call the customer options team and see how much they'll charge you for an unlimited package.  When I swapped my package to unlimited, it saved me £1pcm.
Kevin

[#3]

Many thanks for taking the time to reply.
I agree 'unlimited' would be the easiest option, however this situation is cause by a specific 'event' that happens twice a year, so the economics don't quite work, as the rest of the year the usage is minimal.
I think (but I don't know) that http services are less bandwidth intensive than puer P2P streaming services.

[#4]

Alan,
The issue is that "streaming" is done over a number of technologies.  P2P is a specific consumer of bandwidth in its own right.  If the 'specific' events are predictable then may be a simple answer is to shut down access during the event due to "historical abuse of the facility".

[#5]

That is what I am thinking, apply a password on the wifi on a need to know basis during that period.

[#6]

Alan,
I hope that there is a password on the wifi generally, such that only (from example) club members and guests can access it, thereby inhibiting any passing Tom, Dick or Harry trashing your allowance downloading who knows what on any other occasion.
Then changing the password during such events to need to know (and back to normal afterwards) will deliver the control you seek without getting into the difficulty of port lock outs.
HTH,
Kevin