FOCUS: SYSTEM OVERLOAD

The information superhighway is falling prey to traffic jams and congestion as an increasing number of users and features test the limits of the Internet. There is gridlock on the information superhighway. Students have complained that they have had trouble getting on-line, and officials have cited the recent influx of Internet initiatives as a source of the congestion. But the University is doing everything possible to alleviate this situation. Daniel Updegrove, associate vice provost for information systems and computing and executive director of Data Communications and Computing Services, attributed the overwhelming difficulty of connecting to the system to the increasing number of students using it for both personal and educational purposes. "The general sense is that more faculty are building networking into coursework," he said. "And it is pretty common to have homework distributed on the 'Net." One of the departments that makes exhaustive use of the Internet is the English Department. Undergraduate English Chairperson and English Professor Al Filreis said his department uses listservs -- electronic mailing lists that distribute e-mail -- instead of newsgroups as an adjunct to courses because "they are a better supplement to in-class discussion." He said applications such as Penn MOO -- or Multiple User Dungeon Object Oriented, an on-line virtual environment that supplements English 88 -- are small drains on the system, adding that PennNet is more congested from personal use. "The real drain on the system is the student who has e-mail, and receives many messages, but never reads his or her account and/or does not delete messages," Filreis said. Updegrove also cited e-mail as a drain on the system, but for a different reason. "If you get more users than the design capacity, it will be slow," he said. Updegrove added that it is the number of people logged on, not the actual e-mail use, that affects the system. "We have a lot of people using e-mail, but an e-mail user is not affecting the network much at all," he said. "Any amount of people logged on will cause congestion." The most salient problem is when students must compete to enter the modem pool, Updegrove added, describing the situation as a "peak loading problem." He said the University has 300 modems. This is sufficient except during the prime hours that students and faculty log on, which Updegrove cited as being from 8 p.m. to 1 a.m. "To the extent that students can adjust their connect time, they can reduce the chance of encountering busy signals," Updegrove said. He said DCCS has compiled statistics that indicate the system is processing approximately 900 people an hour, and that the average session is 20 minutes. About 15 modems becoming available every minute. "So it pays to just keep trying," he said. "On average, one modem will become available every four seconds." He added that his department has been attempting to increase the size of the modem pool, but it is facing a temporary storage problem. "We are thinking of taking out 60 of the older modems and putting in 120 newer, more space-compact modems," he said, adding that DCCS has been adding 60 new modems to the pool each semester for the last four semesters. But there is a problem because this is very new technology, Updegrove said. "We don't want to employ the new stuff without testing it," he said. He said he hopes the testing will be done in the next week or so, allowing DCCS to order the new modems. Updegrove added that some of the time the modem pool is busy because outside users are on it. "It is strictly prohibited for Penn people to be sharing their network ID with people outside the Penn community," he said. Besides e-mail, another strain on the system is an application called CU-see-me -- a program for the Macintosh or IBM which permits video transmission over the Internet. This system has been available to the University for about a year and a half. While this program uses up a lot of memory, Updegrove said he does not think there is enough use of it to cause a problem, adding that most users still do not have video cameras connected to their computers. "If we get tens of people doing videos, then that could be a problem," he said, adding that this program can be used in different degrees of intensity, which varies its effect on the system. "If you crank it up to irresponsible levels, it will have a much larger impact on the network," Updegrove said. He added that more students are using PennNet because of the increased number of services it is able to integrate. He cited as an example the fact that the School of Arts and Sciences is now using the Internet for advising purposes. "I think students are finding the Internet is an interesting place to explore," he said."It is quite striking how much information is available world-wide on the Internet. "And given that this is growing in other universities, the number of people on the Internet is growing," Updegrove added. Anthony Rutkowski, executive director of the Virginia-based Internet Society, said the predominant function of the Internet is moving files -- which is done through ftp, or file transfer protocol service. Rutkowski added that the second most-used service is the World Wide Web, which links of information throughout the world in a series of virtual pages, while the third most-used feature is newsgroups. "E-mail, in terms of bytes, is actually rather a small portion of the traffic [on the Internet]," he said. Updegrove said DCCS is trying to upgrade the infrastructure of the system as quickly as possible. "Probably the dominant thing we are doing right now besides the modem pool is trying to get ResNet finished as fast as possible," he said. With the ResNet system, each computer uses Ethernet to connect directly to PennNet, bypassing competition in the modem pool and making performance is a lot faster, Updegrove said. He added that DCCS has been working on a four year project to install ResNet in all of the dormitories for the past two years. In that time, 3,500 Ethernet connections have been made in seven residence halls. DCCS has also installed several thousand PennNet connections in faculty and staff offices, as well as in student computer labs. Updegrove said his department just completed another four-year project two weeks ago called "sub-netting," which consisted of upgrading the carrying capacity of the building networks from one megabit per second to 10 megabits per second. And three weeks ago, DCCS installed the first Ethernet switch in the David Rittenhouse Laboratory, which segments the building by floor so each department has 10 megabits of its own. "This enables math and physics to have their own 10 [Megabits per second] 'collision domains' instead of sharing the building Ethernet," he said. Updegrove added that the University is anticipating employing these switches in the busiest buildings on campus. In August, his department upgraded the campus Internet gateway, from 1.5 Megabits per second to four Megabits per second, he said. "And we are likely to upgrade it to something higher than that in the course of the summer," he added. Updegrove said DCCS is going to upgrade the central campus backbone from 10 to 100 Megabits. He added that the University recently upgraded the speed and capacity of key campus server machines, including Mail.sas, Netnews, Dolphin and Pobox. Updegrove said the key is to stay a little ahead of the demand. "You don't want to be a lot ahead because the prices decrease every year and you can't buy more than you can afford," Updegrove added. For the past 10 years, DCCS has been attempting to project what the level of traffic on the Internet will be in an effort to keep the whole system in balance. But Updegrove said upgrading the system is a never-ending process, because DCCS must continually go back and upgrade the wiring of the first sections wired on campus. Engineering junior and e-mail expert Meng Weng Wong said the University has succeeded in terms of "networking and computer stuff." He said our system has served as a model for other universities. "A lot of other schools are following in our footsteps, initiating a ResNet program that looks like ours," Wong said. And Filreis said the University should do everything possible to "support, maintain and if necessary expand the technical structure to enable this revolution to go forward." "It's bang for the buck," he said. "The qualitative change in how we can conduct education -- and enhance intellectual interaction with our students -- is worth a hundred times to us the cost of the technology."