Bennington College
Computer Science
Joe Holt
November 10, 2005

Notes on Campus Networking and Computing

1. Internet connection

IT should inform the community of network problems. I think this should happen whenever there’s a problem with our T1 service provider, or with email servers, critical file servers, etc. Major internet service interruptions could generate automatic email notifications. Email interruptions could be announced on a webpage. There ought to be an IT webpage that lists current troubles, with contact info and form to report problems.

Network management should be transparent. The community should be well-informed of network management decisions and network performance. For example, there should be a clearly-stated policy regarding the packet shaper: what the bandwidth limits are, when and why machines get blacklisted, etc. I’ve seen some school websites that have webpages with bandwidth history graphs. I think the student body is sophisticated enough to benefit from this openness.

Greater bandwidth. We should not be content until the average download speed equals an off-campus DSL line.

2. Wireless on campus

The campus should be blanketed in wireless. In my opinion this has the greatest bang-for-buck of anything we could do. Use inexpensive access points (~$100) every 150 feet of building space. They shouldn’t require additional wiring, but can plug into existing ethernet jacks (each access point would provide an additional ethernet plug). They can also be powered over ethernet to reduce electrical outlet clutter. They should be everywhere, with at least two on every floor of every house. They should be configured as one large WDS (Wireless Distribution System) network, instead of the fiefdoms of exclusive wireless networks we have now. This would be a huge win for students and could be implemented quickly and easily.

Desktop machines should be wired. I noticed that the desktop machines in the computer center are networked via wireless cards. This is bad for several reasons. For one, busy workstations should be kept off the wireless. Second, wireless is twenty times slower than wired ethernet. We ought to be promoting the desktop machines as the high-performance workstations that they are. As it is, they are hobbled by their slow network hook-ups. This would require additional wiring in the computer center.

3. Infrastructure

Gigabit switches everywhere. Networking between computers on campus is slowed down by slow switches (topologically similar in function to electric power strips). This limits the usefulness of file servers and collaborative network services. Here’s a simple way to think about it. Hard drives read and write at 500 megabits/sec. Gigabit networks are twice as fast as that (1,000 mbit/sec, hence the name) so it’s possible for our network to feel as fast as a hard drive. However, we have older technology 100 mbit/sec switches on campus. These bottlenecks limit network speed to five times slower than your hard drive. This has a big impact on collaborative work, showing movies in class from a server, among other services. The newer computers we’ve purchased have gigabit network connections built-in, but they’re limited to one-tenth their speed when they’re plugged into our network. Gigabit switches can run between $400 and $1,500 each (the "managed" switches from HP are more expensive).

Off-campus access. This is another big bang-for-the-buck item. Set up VPN software on the existing servers. I did a prototype set up last term and found that it was easy to configure and it worked reliably. The value of off-campus access for part-time faculty, ow-residency students and those who live off-campus (e.g., me) can’t be overstated.

There should be cheap utility servers in every subnet. I think there should be cheap servers spread around campus to be used as general purpose IT boxes. They can be used to monitor the network, provide subnet-centric services like printer discovery, etc. Each can be way cheap ($200).

The housing subnet should be split. I noticed that all of the houses are on one subnet. This could be a huge detrimental factor in on-campus networking, where the traffic of hundreds of student computers are all slammed onto the same wires. My old-time rule-of-thumb is to have no more than fifty computers on a subnet. Perhaps the switches alleviate this, I don’t know, but I think it should be investigated and improved if necessary.

Automated backups. Faculty computers should be automatically backed up. There are many commercial packages that do this well and work in the background whenever the computer's on.

4. Services

Email should be treated as mission-critical. Email cannot go down. Ever. All measures possible should be taken to ensure this. Email should be treated as the critical utility that it is, just like power and water. It’s typical in organizations to have redundant backup mail computers, redundant mail storage, and people on-call 24/7 should anything go wrong.

There should be support for email groups. We should have a simple web-based system for faculty to create email groups. Also, email groups should be automatically created every term from class lists. There should be discipline-based groups for communications within disciplines, building-based groups for facilities announcements (Where are we supposed to park this week?), etc.

Authenticated SMTP for off-campus access. If the SMTP mail server had authentication, then it would be possible to send and receive mail from off-campus. It would also be possible to use a Bennington email account through Google’s gmail web-based email service, and other similar services. (I would’ve done our web-based email this way, using authenticated mail and a third-party’s web front end.)

Printers should be easier to use. Students shouldn’t have to manually enter IP addresses on their computers and laptops. The utility servers I mentioned above could run software making it easy for laptops to automatically be configured for printing (using Rendezvous service discovery, available on Macs and PCs).

Blogging servers, wiki servers, media servers, file servers. This is an entire class of services that I think IT should be providing to the academic community. Modern journaling (blogging) websites for classes, collaborative websites via wiki servers, streaming audio and video servers, as well as much easier file access to the existing faculty and student file servers (FTP doesn’t cut it in the 21st century). These can all be set up incrementally and easily on existing hardware using free or nearly free software. For example, I’ve set up a dozen blogs for various classes on campus using an inexpensive software package on the computer in my office (see for examples Sampling - Music, Logic Machines - Computer Science, Code and Creativity - Digital Arts/Computer Science). Wiki software is free and I'm using it extensively for my classes (see my Computer Science pages, for example).