Reliability despite the elements

Given the millions of penguins dotting the Antarctic landscape, it's perhaps appropriate that Linux whose mascot Tux would feel right at home on the world's coldest continent has earned a key role in the IT infrastructure supporting the British Antarctic Survey (BAS, at www.antarctica.ac.uk).

The BAS maintains three permanent bases Rothera (68ºW), Halley (26ºW) and Faraday (64ºW) and a number of smaller research outposts scattered across the Antarctic continent and nearby islands including South Georgia's Bird Island (38ºW), Signy (45ºW) in the South Orkney Islands, and Fossil Bluff (68ºW) and Sky-Blu (70ºW) on the mainland. Rothera, the largest base, hosts up to around 120 people during summer months, while the remote island of Signy has just eight.

BAS activities are spread across geoscience, biological sciences and physical sciences and include activities such as animal monitoring, glaciology, atmospheric studies, geology and geoscience. With such a wide variety of scientific work going on, a good communications infrastructure is a necessity.

At Rothera, a conventional LAN connects a pair of Novell NetWare 4 servers with around 15 Windows NT-based Viglen PCs and a range of special-purpose Unix workstations including Sun Solaris and DEC Alpha-based workstations. An Oracle 8 database supports biological studies such as wildlife monitoring, while niche scientific software including SAS, Minitab, IDL, and GenStat is heavily used for data analysis. Annual resupply flights bring new equipment, while the station is staffed so that there's always at least one technically qualified administrator able to handle any problems.

Although the Rothera base is wired like any conventional office, the unique operating environment at the Halley base which was built on stilts and is regularly jacked up to keep the offices above the accumulating snow forced the BAS team to become somewhat more innovative. Halley, which sits on a 300 metre-thick ice floe, has a similar IT environment to that at Rothera, with around 40 Unix and Windows NT workstations used for all manner of scientific experiments and spread between three buildings on the site.

Networking the Halley base proved more difficult, however, with the introduction several years ago of atmosphere-monitoring radar equipment that inadvertently produced massive amounts of radio interference. This caused substantial interference with conventional LAN cable, a problem that the BAS eventually solved by laying fibre-optic cabling between the three buildings at the site.

Fibre-optic cabling also resolved ongoing issues with static electricity buildup in the copper cabling that had been caused by Antarctica's extremely dry climate. "Although there is an enormous amount of ice and snow in Antarctica, it's very low humidity and precipitation is very low; in many areas it's almost like a desert," said David Blake, head of technical services with BAS.

"This leads to problems with electrostatics, and in the past we actually had a static charge go through a hub into a server and kill the server. A few years ago, we also had DATs installed where we had an enormous problem with data being erased. We had to put humidifiers in the computer rooms, and fibre-optic wiring has overcome not only the problems of electrostatic buildup but also the strong magnetic fields we get because we're so far south."

Another environmental condition playing havoc with IT systems is the cold, which significantly reduces the life of batteries in the Toshiba notebook PCs used by researchers venturing out into the field, who can often stay away from the base for several months. To minimise the effect of the cold, researchers keep notebooks in field tents and even bring the systems into their sleeping bags during the frigid nighttime.

With precautions helping minimise the BAS's exposure to natural forces, the technology team which is mirrored at the organisation's Cambridge, UK headquarters and development centre has been growing increasingly fond of Linux as a way of reducing its exposure to the idiosyncrasies of operating system misbehaviour.

One of the survey's key systems which handles the transmission of data messages over the critical 64Kbps Inmarsat satellite communications link was built entirely in Linux, which is also being increasingly used for standard network data serving and scientific applications. "The system we had before tended to use proprietary standards, and we decided we'd like to have a very reliable system," said Blake. "We've had the new system up and running for two years and it's been totally reliable."

Perhaps the strongest testament to Linux's reliability is the fact that the BAS decided to forego Windows NT and NetWare to implement a Linux-only environment at its remote Bird Island, South Georgia wildlife monitoring station. The network simply keeps running without a problem, said Blake, who has been more than impressed with the operating system's robustness and flexibility.

"We're not an enormously wealthy organisation, so we try to make sure what we do is reliable," he said. "We're now using Linux a lot. [At Bird Island] we had a base where we wanted something that was going to be very reliable and simple because there wouldn't be any computing and IT support. We find that when we have NT, NetWare and so on that they need that much more support, whereas with Linux products if we can get them going and set up, they tend to keep going and remain totally reliable."