New campus sweetheart: 1-Meg Modem - at Northern Illinois University - Product Information

Communications News, July, 1999 by Alan Stewart

NIU adopts high-speed solution.

Buoyed by its initial trial of Nortel Networks' digital subscriber line (DSL) products, Northern Illinois University (NIU) has ordered 1,000 additional second-generation l-Meg Modems. Its main campus, located in De Kalb, currently has 160 people on line, and the college plans to connect 2,000 students within two years. What are the pros and cons of the Nortel solution?

EVALUATION

Wally Czerniak, director, computer and telecommunications operations at NIU, says the entire project has worked very smoothly from the original trial of 50 modems. "The main advantage of the Phase 2 product is additional speed," he says. "Our students want LAN capability in their dorms, and they flooded us with inquiries as soon as we advertised it."

The new modem provides 1.28 Mbps downstream (toward the user), 380 kbps upstream (toward the network), plus multiport capability. Based on these attributes, NIU expanded its DSL dorm applications and even is replacing some standard LAN connections in its business, office with 1-Meg Modems, reports Czerniak.

He notes that, with a megabit of throughput, students complete their homework on time, access their teachers for multimedia help, and can communicate with class peers in a more effective manner. Web browsing also becomes a more pleasant experience due to shortened download times. "Each class has its own list server, users see their syllabus on our Web site, and more and more of their class work is available on line. Because speed is of the essence in accessing this data, the l-Meg Modem has proved a major hit with our students."

An alternative to DSL is a shared LAN system, but this architecture can lead to congestion and other problems, observes Czerniak. Because the modem concept is basically a switched Ethernet connection, each circuit is dedicated to each user as far as the CO (central office) interface. This helps users connect to the on-campus ISP (NIU-Net) to access libraries, interrogate file servers, and send mail to each other within the class environment.

Czerniak's team engineered its I-Meg Modem connections to put up to 31 users on one physical subnet. Unlike the architecture used by most telcos and cablecos, this enables NIU to create connections over 10- and 100-Mbps switched Ethernet ports. "We come from a TCP/IP environment, and that's what we know and think," says Czerniak. "When we promise our customers l-Mbps service, that's what they expect to get."

NEXT-GENERATION MODEMS

NIU is now in beta trials for Phase 2 of the project. During the early trial, the modem supported only one IP address. As a result of ongoing developments, two and even four addresses are in the works. "We've retrofitted the software, we've done downloads, and now we can put a 4-port mini-hub behind them," says Czerniak. By way of further support, Nortel is working on new management software, always-on powering arrangements, and improved handshake procedures. "All modems are now remotely software up-gradable," he adds.

Czerniak says there were a few minor problems with noise and interference when using phones and modems at the same time. "A handful of older telephones experienced interference, but the vendor now has incorporated filtering inside the modem, and this is no longer an issue. In fact, the modem has really been splitterless from day one because in the 200 or so we've installed, we only needed filtering for one or two."

Herb Kuryliw, senior network engineer at NIU, says security is handled as an option on the modem. "The nice thing about it is you can set it to the switched-type environment so that nobody can intercept it," he explains. "There's also an ability to limit certain types of broadcast. It's not possible for one user to see another's connection, and this is so inherent in the architecture that some students even complain about it.

"As a default we can bring the modem up in the most secure mode. We can control broadcast because, if someone's playing Doom or trying to hack, it doesn't pass it on to other users. We elected not to go to a shared environment because that means son, cone could be sharing your disk--which implies sharing everything. We bring it all up on the premise where it is most secure, and subscribers can open it up in any manner they want."

The network administrator delegates IP addresses using a server. This is done as simply as possible using DHCP (dynamic host configuration protocol). "It's like installing a modem, it can be confusing," Kuryliw explains. "We wanted to make it as close to dial-up as possible, so it doesn't matter what IP address you get. We use the easiest default setting which is a DHCP call. When users bring this up they get an IP address."

VENDOR PERSPECTIVE

A principal advantage of the 1-Meg Modem is its ease of installation, says Nortel's marketing manager, high-speed networks, Mike Godfrey. "Splitterless ADSL (asymmetrical digital subscriber line) trial results indicate that loop reach and bit errors remain a problem. As telcos roll out ADSL and experience delays, they will look for alternative solutions."