Navy puts new optical networking protocol to the test
- By William Jackson
- Jan 06, 2004
The Navy's Advanced Technology Demonstration Network has successfully used a new optical networking protocol that could help researchers take full advantage of high-performance, all-optical networks.
The Just-in-Time Protocol does fast light path provisioning, setting up optical connections between computers. Researchers from North Carolina State University and the MCNC Research and Development Institute of Research Triangle Park, N.C., developed the protocol, known as JIT.
'JIT addresses some very challenging problems in high-performance computing,' said Hank Dardy, chief scientist for advanced computing at the Naval Research Laboratory's Center for Computational Science. 'It can take weeks to establish an optical connection through a carrier network and minutes to do so with generalized multiprotocol label switching.'
Research scientists exchanging large data sets on the terabyte and petabyte scale prefer to keep the files in optical form during transmission, said Dan Stevenson, vice president of MCNC's Advanced Network Research Division.
'They want to get the electrical routers out of the path,' Stevenson said. 'They want to hook their computers up on a dedicated path.'
In demonstrations on ATDnet, a test group found JIT could set up and release these paths in about 10 milliseconds, or about one one-hundredth of a second.
The first JIT demonstration, for transmission of uncompressed high-definition TV signals at 1.5 Gbps, was in November 2002.
A demonstration in September of last year set up IP data paths linking systems in the ONR's Center for Computational Science, the Defense Department's Laboratory for Telecommunications Sciences and the Defense Intelligence Agency.
A third demonstration, of HDTV again, is scheduled for the coming days.
Fast provisioning of light paths within a wavelength can help make optical networking more efficient.
'We're doing very coarse-grained multiplexing now,' Stevenson said. Optical networks can handle multiple wavelengths, 'but our ability to share a wavelength is very coarse.'
JIT is capable of handling the activity on a time scale of a single microsecond, or one one-millionth of a second, Stevenson said.
'The 10 milliseconds is the time it takes for the electromechanical switches to reconfigure,' he said. 'We want to get to another three orders of magnitude performance, down to a nanosecond.'
That level of performance could enable interactive distributed computing using large data sets, rather than simple bulk transfers that are now being done.
William Jackson is a Maryland-based freelance writer.