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Incorporating the necessary computing tools for all this has been a delicate balancing act for SEA. "We wanted to make sure we didn't step on the traditional ways of navigation and communication aboard a large sailing vessel," says Ed Dennen, network administrator for SEA. That meant providing a reliable network without a link to the Internet, nor to SEA's home network. "With the captains and crew trying to teach students the importance of a self-reliant shipboard community, that community loses relevance if you can e-mail your dorm buddy back home," Dennen says.

Dennen's approach is a peer-to-peer, 10/100-Mbps, twisted-pair Ethernet LAN built out of two NetGear FS308 switches on a ship. Each ship also has three Microsoft Windows-based desktop PCs, four laptops and several pieces of scientific equipment, including a Sea-Bird Electronics Carousel sampling system, which collects water to test for chemical makeup at different depths. The device gathers data, such as water temperature, pressure and salinity.

"The reason we use peer to peer is to keep it simple for our scientists and students, we don't have anyone on board to maintain a network," Dennen says. To reduce potential downtime, SEA outfits each ship with extra switches, laptops and PCs in case of a failure or damage from rough sea conditions.

Before the LAN, SEA students used floppy disks to store their project proposals and papers. "After five weeks of sleeping on the floppies, they couldn't read them and their papers weren't done," says Paul Joyce, chief scientist for SEA. Now the students store their work on the network and CDs.

Such a network setup presents some technological and logistical challenges for Dennen. "The ships come to Woods Hole just a few times a year and are usually at port stops for less than a week between cruises, which is never enough time to do any serious maintenance or upgrade work," he says.

Conditions also are a big factor. The ships aren't air-conditioned, and the extreme temperatures, humidity and salt air encountered during SEA's Caribbean cruise can wreak havoc on computers and wiring. So SEA stores the equipment under cabinets and away from portholes, with Plexiglas sheets over the LCD monitors. "We use LCD monitors in the lab and at library desktops because they require less power and generate less heat," Dennen says. And space is at a premium, so keyboards are mounted under countertops, and laptops are secured under seats in the library for instance. It's not like a typical office, where you can throw cables into the walls, either. "Getting from one ship compartment to another can mean drilling and repairing the quarter-inch steel, watertight bulkhead for 20 minutes," Dennen says.

To replace its older schooner, SEA is constructing a new vessel with preplanned wiring and an air-conditioned cabin for the ship's network equipment and processors. Until now, wireless hasn't been an option for SEA because the steel containers that make up the ships' compartments can block radio frequencies. But SEA will test wireless on the main deck of its new ship and eventually will use wireless within a ship container or compartment, with hardwire between compartments, Dennen says.