It's a step up from today's system, with which forecasts are compiled by regions or metropolitan areas, not neighborhoods. Forecasters have to correlate and decipher textual data manually from different weather detection systems. This text-based weather data leaves a lot to interpretation, so it isn't always accurate, says Randy Chambers, operational manager of the NWS' Network Control Facility, or NCF. The NDFD database makes it easier to glean information from the reams of embedded weather data. "So there's more uniformity and accuracy in the forecasts," Chambers says.
But the weather service's new database was nearly grounded before the NWS issued the first neighborhood forecast. When NWS technicians test-ran NDFD on the agency's customized network simulation tool last year, they determined that the flashy new graphical weather data would saturate its clustered Linux server architecture. The simulation showed that for several minutes each hour, the NDFD database application would consume nearly 90 percent of the existing Dell 2650 Linux cluster's computing resources. As NDFD expanded and evolved with more graphics, the servers would get slower. And the slower the servers, Chambers says, the staler the forecast data.
So this fall, the weather service will buy new Linux superservers, with multigigabytes of memory and a terabyte or more of storage capacity. The existing servers are sufficient for running the early phases of the database system, which is less graphical. Meantime, the weather service will reconfigure the servers to get more mileage out of them. One option is to separate the server cluster and divide up the RAID 5 drives, Chambers says. "Then we can use all the processing power of both 2650s and spread the drives among the servers," he says.
For the new database superservers, NWS is considering an all-in-one Linux superserver architecture that would support the NDFD Informix database, collaboration server, Web server and the NDFD processing system. There are trade-offs with this combo superserver, though. "We're wrestling with whether to throw everything into one bucket. It makes sense from an engineering perspective to have one huge server, with a backup," Chambers says. "But if that server goes down, you've lost all these pieces."
The NWS's Advanced Communications Network Model (ACNM) simulation tool, meanwhile, is like a forecasting system for the weather service's network. The weather service uses it to test-run technology or products before it buys them (see The Hard Sell, below). ACNM is based on OPNET Technologies' Modeler simulation software and runs on a 1.9-GHz Microsoft Windows 2000 server with 2 GB of RAM. It gets real-time data on the weather service's IP/frame relay WAN from the agency's Agilent NetMetrix network monitor.
Discover the benefits of scalable backbone and network services for application and cloud providers.
Network automation is gaining momentum. Here's how you can drive this powerful technology to its full potential.
Subsea cable alternatives can provide a level of comfort for those concerned about disruptions. Realistically, they will continue to play a small, but critical role in the short term.
