What are we doing?

We used to have an allowance of 10GB a week data transfer per ResNet user. We are changing this so that in future we will have no overall limit for the whole week, but limits for the busiest time of day only. The day is divided into peak and off-peak periods:

• Off-peak period (12 midnight-6pm): no limit
• On-peak period (6pm-12 midnight): allowance of 2.5GB a person a week

Why are we doing this?

We have had a ResNet fair usage policy for a while. It tries to make sure that our pipe to the Internet is available fairly to all and not used up by a few.

The evening is the busiest time for ResNet. It is only during the busiest period that our pipe to the Internet can get full and performance suffers. We'd like to reduce usage during this time so the network still works well for everyone on it.

If we have spare capacity during the rest of the day there is no reason that people shouldn't use it then. Some things, like backups or large downloads, you can do at any time.

We are trying as far as we can to provide a service that suits everyone, or at least balances conflicting demands. For example, heavy users can schedule large downloads to take place off-peak without any penalty. As there is no off-peak limit then over a week heavy users will actually be able to do more than they could before. Reducing large transfers during the evening means that sensitive real-time usage (such as webcams, telephony or games) will work better during the busy period.

When does it start?

Monday 23rd April 2007 (start of summer term)

What happens if I use more than the allowance?

The morning after you exceed your weekly on-peak allowance your ResNet connection will be automatically moved into a different network segment and will stay there for the rest of the week. This network area is shared with other heavy users. Your connection may be much slower. You will still be able to get at websites, email, and internal University resources like Blackboard, but other things such as Skype, webcams or Internet radio will stop working.

How do I know how much I'm using?

See Manage My ResNet to view your usage.

More questions?

Please first see the fair usage policy for more information and then email us if there is more you need to know.

Comments?

If you've got any comments or suggestions on this please comment on the blog below.

Update 2007-06-19: Comments are now closed as there have been no genuine comments submitted recently, only spam. If you want to comment on this article, please contact the ResNet Helpdesk.

At 10am this morning, we increased the maximum upload speed that each user can use on ResNet. We're hoping that by allowing you to upload to the internet quicker, skype (and other VOIP applications) will become more reliable.

For info, the maximum download speed is currently set to 8Mbps, and the maximum upload speed has been increased from 2Mbps to 8Mbps (per user).

We will be keeping an eye on the traffic graphs and the packet loss/latency to make sure that this doesn't cause any unforseen problems.

Don't forget that uploads are included in your weekly traffic allowance, which you can check online keep an eye on your usage so that you don't get caught out!

The problems we were experiencing with our new bandwidth management appliance (see  bandwidth-management-teething-problems) seem to have highlighted a design flaw in the appliance itself.  We're working with the vendor to fix the problem, although we're not expecting a patch from them for another two weeks or so.

Latency and packet loss are now back to the same levels that they were in January.  However, these levels are still much higher than they were at this time last year.  This is mainly because there's a *lot* more traffic on ResNet than there was this time last year!

We will be making some changes next week which we hope will improve the situation further, we will be documenting details of the changes (Most importantly the details of the times when we put them in place) on the blog.

We've set up a new category for bandwidth related posts, so if latency/packet loss etc is of special interest to you (eg if you're a gamer) you might want to keep an eye on the  bandwidth management category.

Our existing bandwidth management appliance is getting a little long in the tooth and whilst it can cope at the moment, it isn't able to scale to match our needs for the future. So we're replacing it, and over the last couple of days we've been trialing the new system.

Initial reports are mixed. Some users of services such as Skype have reported improvements, others have seen things get noticably worse. Eg at peak times last night, the latency on the network increased substatially compared to our previous solution.

One side effect is that the new system allows people much more "upload" bandwidth during off-peak times than we had anticipated. This seems to have caught out a few people who had left their P2P applications running, and caused them to go over their weekly bandwidth quota.

As this was unexpected, we have taken the decision not to transfer anyone to the restricted network on Monday. However, you do still need to keep an eye on your bandwidth usage as we are likely to go back to using the restricted network on the 12th Feb. Don't forget that even if you're not downloading anything, your P2P software may be uploading to other people. The best thing to do is to shut it off if you're not using it!

We're still learning about the new system, working closely with the suppliers to tweak it so that we get the best possible performance out of it for our environment. We think last nights latency problems were caused by a configuration oversight, which we will look into as soon as possible next week.

For the moment though, we have moved the network back to our previous bandwidth management appliance and we intend to leave it that way over the weekend.

We're sorry for any inconvenience caused while we're finding our feet with the new appliance. We hope that any problems will be short lived, and in the longer term you should notice an improvement in the quality of your network connection.