Bandwidth Management

Posts relating to the things we’re trying to manage the bandwidth available to ResNet users

Most people are using ResNet Wireless this year, probably because it’s really convenient (who doesn’t want to be able to lie on their bed and watch endless videos of kittens on youtube?) but did you know that ResNet Wired is up to 5 times faster?

Internet speeds are limited by the slowest technology in the path in the chain.  At home that’s usually the bit between your broadband router and the internet, but on ResNet Wireless our connection to the internet is so blisteringly fast that the bottle neck can be the wireless technology used by your laptop.  There are two main wireless technologies on ResNet Wireless, 802.11g and 802.11n

We have the newer, faster 802.11n technology in place on about 80% of ResNet, and in our tests the speeds work out something like this:



Although these tests were done using an actual ResNet Wireless connection, your wireless connection might well be slower.  Our tests were done at a quiet time of day, and we were sat in the same room as the wireless router.  If all your flatmates are using ResNet Wireless at the same time as you, or if there are any walls between you and the access point then you can expect your wireless speeds to be a bit slower than ours.

However, neither of those factors effect the ResNet Wired service!

ResNet Wired

Blimey! That’s a bit quick that is!

To set up your computer to use ResNet Wired, just plug your computer into the ResNet socket in your room using the cable provided and follow the connection guide we gave you when you moved in.  If you don’t have a cable or a connection guide, ask your hall office or senior resident.

While we already compare favourably with commercial broadband providers (on price, speed and bandwidth quotas) there’s always room for improvement – so we’re rethinking how much bandwidth we give you on ResNet.

Making your usage quota easier to understand

Currently you have two bandwidth quotas, one for off-peak and one for on-peak times of day.  Going over either quota lands you in a slow network for the rest of the week – at all times of day. This is confusing, and terribly inconvenient if you want to skype your friends back home during peak hours…

So, we’re getting rid of peak-time!

We’ve combined the on and off peak quotas to give you a single quota of 48GB per week (For ResNet Standard) or 81GB per week (For ResNet Max) – no more worrying what time it is!

We’ve been trialling this change since 23rd May and it’s been going pretty well so far.  The My ResNet control panel, and the Bandwidth Gadgets don’t fully know about the change yet, so your on-peak usage is being reported as zero.  If the trial continues to work out ok, we’ll have to see about fixing that!

If 81GB per week isn’t enough for you, you can still buy extra chunks of quota through My ResNet.

Making your connection even faster!

Not content with making things easier, we’re making them faster too!

Starting Monday 13th, we’re going to increase the speed of ResNet wired connections to 50Mbps symmetric – That’s 50Mbps download speed, and 50Mbps upload speed.  Once we’ve made that change, ResNet connections will be faster than BT Infinity Broadband (which gives you 40Mbps download speed, and 10Mbps upload)

Why is this awesome?  (Apart from it being obvious that faster is better!)

Well it means you can take full advantage of cloud based storage/backup solutions such as iCloud, Windows Live SkyDrive or Ubuntu One. It makes uploading photos or video to facebook/vimeo/flickr/youtube super quick, but most importantly – whatever cool new internet functionality is coming round the corner, we want your ResNet connection to be ready to handle it.

At this stage, we’re not making any changes to the speed of the wireless network.  We can make it a bit faster than it is at the moment, but we can’t make it quite as fast as the wired network.  So to take full advantage of the speed boost you’ll need to use your wired connection.

“With great power comes great responsibility” – Spiderman

Once your connection is faster than a very fast thing going downhill on rollerskates – it does mean that it’s easier to use up all your bandwidth quota.  We’ve done some sums and we think a bittorrent client serving up something popular (like an Ubuntu Linux DVD image) left unchecked could rip through the ResNet Max weekly limit in under 4 hours – on upload traffic alone!

If you’ve got any filesharing software on your computer, you might want to limit how much it can upload to the internet.  Most programs allow you to specify a maximum upload speed – we suggest setting this as low as you can get away with!

Not-that-small-really smallprint: All the features mentioned above are being trialled, we reserve the right to end the trial at any time if things start to melt.  We’ll make a decision about what next years network speeds look like based on the results of the trial, so the above features may or may not be available for the 2011-2012 academic year.

Oh, and they apply to ResNet only.  The VisitorNet service got an 8 fold increase about a month ago but that’s as far as we can push that for the moment.


If you’ve got any questions or comments about the trials mentioned above, hit the comments below!

We’ve got a new version of the ResNet bandwidth quota monitoring sidebar gadget, which fixes a problem experienced by Windows Vista and Windows 7 users, where the gadget refused to accept their keys.

If you tried the sidebar gadget and it didn’t work, upgrade to the latest version from and give it another go!

Information Services are carrying out some essential systems maintenance on the 11th August 2009, 10:00-10:30 which affects the following ResNet systems:

  • My ResNet
  • ResNet in-room Registration System
  • ResNet Helpdesk troubleshooting tools (including those used by the out of hours helpdesk)
  • ResNet Network Monitoring system (the traffic lights on the ResNet home page)

All fully registered ResNet connections will continue to function normally throughout this maintenance period, so most people won’t notice anything.

There are several other University systems which are also affected by this maintenance, for more details see the IS News website:

If you’ve looked at MyResNet recently you’ll have noticed that the off-peak weekly allowance cell in the Network Usage table has changed from ‘unlimited’ to 35GB. Currently we are not automatically restricting users based on their off-peak usage but we are working towards this goal.

Looking at this table you should be able to work out that if either the off-peak allowance OR the on-peak allowance exceed 100% AUP then your connection will be moved into the restricted network. Clever usage will allow up to 40GB weekly traffic (35 off + 5 on).

As I said before, the off-peak allowance is not active yet, but will be in the near future. The on-peak allowance is still in operation as it has been all year.

From current usage statistics, we anticipate that less than 1% of our users will be affected by this change. For example, last week 0.56% of users transferred data in excess of 35GB off peak and the week before it was just 0.33% (although term only started on Wednesday of that week).

Currently off-peak is midnight to 6pm (18 hours) and on-peak is 6pm to midnight (6 hours).

As always, we welcome constructive feedback.

Well it’s Christmas and lots of students have disappeared for the holidays so it’s only fair that we increase the usual 5GB weekly peak-time usage to 10GB.

Peak-time is unchanged, 6pm to midnight.

The limit will be reduced back to 5GB per week from Monday 7th January 2008 so try not to get caught out 😉


During the vacation period (starting on Monday 25th June) we are increasing the peak-time usage 10GB per week as the network is less busy. We may review these limits throughout the vacation period.

Off-peak periods remain unlimited.

Peak-time is 6pm to 12 midnight and off-peak time is 12 midnight to 6pm

Enjoy 😉

Week 5 (Monday 21nd May to Sunday 27th May)

Day Restricted Network Total Restricted Average Restricted Days Warning Emails >80% Total Emails UL/DL Ratio All Restricted Users
Tue 22nd (Early am) 0 0 0 4 4 0
Wed 23rd (Early am) 2 (<0.05%) 2 (<0.05%) 5 1 5 0.42
Thu 24th (Early am) 3 (<0.07%) 5 (<0.12%) 4.4 12 17 0.45
Fri 25th (Early am) 9 (<0.22%) 14 (<0.35%) 3.5 29 46 0.65
Sat 26th (Early am) 25 (<0.62%) 39 (<0.97%) 2.5 23 69 0.43
Sun 27th (Early am) 24 (<0.60%) 63 (<1.57%) 1.9 45 114 0.32

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.

This is part of the occasional series of newsletters sent to all ResNet subscribers. In this edition: Peak usage limits increasing to 5GB per week; ‘Second Chance’ System; Jobs with ResNet

Peak usage limits increasing to 5GB per week

We are pleased to announce that from Monday 21st May 2007 the weekly peak-time usage allowance is to be increased to 5GB.

It has always been our intention to let ResNet subscribers use any spare capacity. We are confident that we have enough spare network capacity at the busiest time of day (6pm to midnight) to allow this increase.

We are constantly reviewing the peak and off-peak usage so that the best possible quality of service is maintained for the often conflicting needs of ResNet subscribers.

For more information on the peak-time system see

‘Second Chance’ System

We are developing a ‘Second Chance’ system that can be used once per term to allow restricted subscribers back onto the ‘normal’ network. An announcement will be made on our blog when the system is in place. If you are moved to the restricted network, and the ‘second chance’ system is in place, then the email we send you will contain information on how to use it.

Jobs with ResNet

There are still a few days to apply for a number of technical and non-technical positions available for full-time work this summer vacation and part-time work from Freshers’ week onwards.

To apply, please see

The closing date is 10am, Monday May 21st.

Best wishes,

The ResNet Team.

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.

We are pleased to announce that from Monday 14th May 2007 the weekly peak-time usage allowance is to be increased from 2.5GB to 4GB.

We have been very pleased with the improvements to packet loss and latency that real-time application users find essential. These applications should now be working without trouble at all times of day.

We now find that for the first time in ResNet’s history we have spare capacity at the busiest time of day (6pm to midnight) and it has always been our intention to let subscribers use this capacity, hence this increase.

The limits will be reviewed again in a week or two and changed accordingly. The aim is to allow as much use of the available capacity whilst still maintaining quality of service to all subscribers. This is a learning curve for us, as having a peak-time limit is a culture change and we could not easily predict usage patterns, hence the relatively low 2.5GB initial limit.

Last week a total of 191 subscribers were moved to the restricted network, well under 5% of all subscribers, with an average restriction of 2.86 days per restricted user. If this were scaled up to all of ResNet then the average restriction would be < 3 hours per user per week.

We hope this change meets the approval of all who have asked for an increase, however, I’m sure not all will be fully satisfied with our attempts to please all ResNet subscribers.


The ResNet Team

Week 4 (Monday 15th May to Sunday 20th May)

Day Restricted Network Total Restricted Average Restricted Days Warning Emails >75% Total Emails UL/DL Ratio All Restricted Users
Tue 15th (Early am) 6 (<0.15%) 6 2 3.70
Wed 16th (Early am) 2 (<0.05%) 8 (<0.2%) 5.75 11 13 1.57
Thu 17th (Early am) 9 (<0.22%) 17 (<0.42%) 4.82 13 26 0.69
Fri 18th (Early am) 13(<0.32%) 30 (<0.75%) 4.03 38 64 0.46
Sat 19th (Early am) 24 (<0.60%) 54 (<1.35%) 3.13 52 116 0.37
Sun 20th (Early am) 38 (<0.95%) 92 (<2.30%) 2.25 79 195 0.38

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.

We are making the initial results of the new policy publicly available so users are aware of what’s going on.

We have calculated, based on past usage, the number of people that may be affected by the new policy. This data is in the expected column.

Week 1 (Monday 24th April to Sunday 29th April)

Day Restricted Network Total Restricted Average Restricted Days Warning Emails >80% Total Emails UL/DL Ratio All Restricted Users
Actual Expected Actual Expected
Tue 24th (Early am) 15 (<0.4%) 21 6 13 2.75
Wed 25th (Early am) 58 (<1.5%) 50 73 (<1.8%) 71 5.21 31 44 1.60
Thu 26th (Early am) 56 (<1.4%) 69 129 (<3.2%) 140 4.68 59 103 1.38
Fri 27th (Early am) 39 (<1%) 80 168 (4.2%) 220 4.29 104 207 1.20
Sat 28th (Early am) 62 (<1.6%) 100 230 (<5.8%) 320 3.67 141 348 1.07
Sun 29th (Early am) 62(<1.6%)* 112 292 (<7.3%) 432 3.10 186* 534 0.88

Notes on Tuesday 24th:

The 15 users that were moved to the restricted network had a combined upload to download ratio of 2.75 so it is likely that they were moved because the either couldn’t, wouldn’t or didn’t know how to control the upload traffic.
For probably the first time in the history of ResNet there was noticeable drop in traffic between 6pm and midnight. There was no increase in latency and no packet loss so this is all very positive.
One minor problem was noticed for the hour before 6pm. Latency increased slightly because the upload link was saturated which would have had a detrimental affect on real-time applications. We are looking into solving this.

Notes on Friday 27th:

The number of people being moved to the restricted network is decreasing which suggests that people are not doing P2P during peak times (our traffic graphs also support this). The latency and packet loss for the vast majority of the day is excellent so hopefully all the real-time application users are happy. There is still a slightly higher latency spike for the hour before 6pm – this is probably when people are cramming in downloads before the peak period begins.

Notes on Sunday 29th:

* The script that runs every evening failed on its early Sunday run because of an error in the code. This has now been corrected. 62 people were not moved to the restricted network and the 186 warning emails were not sent to users that were over 80% usage.

Week 2 (Monday 30th April to Sunday 6th May)

Day Restricted Network Total Restricted Average Restricted Days Warning Emails >80% Total Emails UL/DL Ratio All Restricted Users
Actual Expected Actual Expected
Tue 1st (Early am) 13 (<0.3%) 21 6 9 4.06
Wed 2nd (Early am) 22 (<0.5%) 50 35 (<0.9%) 71 5.37 23 32 2.40
Thu 3rd (Early am) 30 (<0.8%) 69 65 (<1.7%) 140 4.74 35 67 1.49
Fri 4th (Early am) 40 (<1%) 80 105 (<2.6%) 220 4.08 68 135 0.80
Sat 5th (Early am) 32 (<0.8%) 100 137 (<3.4%) 320 3.59 100 235 0.79
Sun 6th(Early am) 54 (<1.3%) 112 191 432 2.86 169 404 0.65

Week 3 (Monday 7th May to Sunday 13th May)

Day Restricted Network Total Restricted Average Restricted Days Warning Emails >80% Total Emails UL/DL Ratio All Restricted Users
Actual Expected Actual Expected
Tue 8th (Early am) 9 (<0.3%) 21 6 7 1.87
Wed 9th (Early am) 18 (<0.5%) 50 27 (<0.7%) 71 5.33 20 27 1.20
Thu 10th (Early am) 28 (<0.7%) 69 55 (<1.4%) 140 4.65 41 68 0.90
Fri 11th (Early am) 56(<1.3%) 80 111 (<2.6%) 220 3.82 68 136 0.57
Sat 12th (Early am) 58 (<1.3%> 100 169 (<4.2%) 320 3.54 78 214 0.52
Sun 13th(Early am) 91 (<2.2%) 112 260(<6.5%) 432 2.65 93 307 0.42

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.

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.


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.