By Jeff Stutz

In response to the increasing concern about our academic computing system, particularly with the speed and reliability of the mail and file system, we sent our Webmaster / in-house technical guru Jeff Stutz to interview several key personnel at AcIS.

The following is a summary of the discussion between Jeff Stutz (The Moment Reporter), Bill Chen (Head of Networking), Maurice Matiz (Manager of Consulting Service), Havy Kaye (Lead Programmer) and Rob Catalano (Lead Consultant).

Question
Why does PINE use POP (Post Office Protocol) to retrieve email ? It slows down mail transfer, needlessly sends plain-text passwords across the network, and is a general nuisance.

Answer
POP has a couple advantages over using a standard UNIX read-a-file method of handling mail. It allows users to read mail from their own machines using POP-compliant programs such as Eudora.

In addition, it performs mailbox locking while transferring the new mail; NFS lacks such mechanisms. This locking ensures that your entire spool (mailbox) file does not get nuked if you receive a new piece of mail while reading the old.

Sending plain-text passwords across the network has been avoided by implementing Kerberos authentication.

Question
Why even bother to use NFS at all? It is a very old method of sharing files. AFS (Andrew File System) is one example of a newer way that can provide all necessary locking. It even has advantages such as letting users mount and control their own filesystem volumes, robust permission options and automatic daily backups.

Stanford has been running AFS for a number of years, and their network is very stable and relatively speedy. IBM's research divisions use it quite effectively to share data.

Answer
Converting the current filesystem to AFS would be expensive and take a lot of time. AcIS has already implemented the above solutions to the problems that running NFS poses.

Question
Most people have noticed that the network has been very slow recently, most notably the POP servers. What is being done to improve the performance of the network?

Answer
Several steps are being taken to speed up performance. another mailhub has recently been installed. As for the network itself, the largest problem with performance is due to overloaded routers.

In response, new routers are being installed (and new subnets created) that, in addition to improving performance, make it easier to upgrade specific parts of the network as the need arises. The campus backbone itself (FDDI) and the connection to the Internet (one T3) are fast enough to handle their traffic without any problems.

Question
Aside from providing day-to-day computing services, what new initiatives have AcIS undertake recently?

Answer
AcIS pioneered the installation of a 155 Mbit ATM network, which is used for full-motion (30 frames per second) video conferencing between campuses. This technology was employed for several remote learning classes at the computer lab at 252 Mudd.

For those users who want to run their own applications on public Macintosh workstations, At Ease 4, which includes a restricted version of the Finder called the Minifinder, will come in quite handy.

New dorms will be equipped with class 5 wiring, which is capable of transfer data at 100 Mbit/sec- ten times faster than the current speed of the RHNO network. The new wiring permits future bandwidth expansion in these dorms.

IMAP clients, which allows user to dynamically retrieve files from remote mail servers, will be supported as soon as they are readily available.

* * *

Since the interview, network performance has indeed improved. It was particularly noticeable when the new mailhub went online.

Although the performance issue has been reasonably address, the reliability of the file servers remains a problem. A few weeks ago, the file system experienced a crash which caused some users to lose a weekend worth of work.

For those who need to run an unsupported application, the 5 Megabyte quotas are brutally insufficient. I suggested that AcIS set up a "/contrib" directory for user-supported applications. They complimented the idea and said that they would investigate ways of implementing it securely.

Despite the remaining problems, I am now assured that AcIS is improving its infrastructure at a reasonable rate. Our computer systems have come quite a way from their states four years ago, when CUNIX the user base was less than one third of what it is today.

It remains to be seen if the ever-increasing demand for power and reliability can be met in years to come.

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