Mobile IP lets users stay connected to roaming, mobile network
The Army's Warfighter Information Network-Tactical (WIN-T) program could provide just as much value for a wide range of civilian activities as it will for soldiers on the battlefield, demonstrating how mobile networking technology can be applied to everything from transportation to disaster relief.
WIN-T eventually will provide soldiers on the battlefield with modern, high-speed communications and real-time voice, video and data services. To achieve that goal, teams working on the program will leverage standards-based technologies such as Mobile IP, which enables people to use a permanent IP address to connect to a roaming, wireless network.
But to get from here to there will take work, not least because the traditional notion of battlefield networking — cables linked to antennas that take time to install and pull down — runs counter to the notion of a mobile force.
"That's the technology challenge of this program," said Jim Quinn, WIN-T program manager for Lockheed Martin Mission Systems. "The whole notion of mobility."
Lockheed Martin is the leader of one of the teams that in August were awarded $75 million contracts for the first two phases of the WIN-T development. The other team is led by General Dynamics C4 Systems.
Both teams will compete to be the sole developer of the 15-year WIN-T program, valued at more than $6 billion. Phase One will last a year, during which both teams will define an architecture for WIN-T. In the two-year second phase, the teams will test their architectures and develop a prototype for the Army to test.
The Army has stipulated that the bulk of the WIN-T development be based on commercial off-the-shelf, standards-based technologies. So the network's core design will have to depend on standards that already exist or are close to completion.
The main technology now in play is Mobile IP, which was standardized as far back as 1996 for use in the Internet Engineering Task Force's IPv4. An updated and more robust version of Mobile IP is being considered for use in IPv6, the latest iteration of the IP standard.
"Mobile IP allows a device [connected to a wireless IP-based network] to keep a permanent IP address, even though it may be roaming from one hot spot to another," said Mark McCabe, regional manager for Army programs at Cisco Systems Inc., a member of the Lockheed Martin WIN-T team.
Higher-level network protocols, such as Transmission Control Protocol, need the IP address to identify users, and the TCP connection is broken if the IP address changes.
That will be important for soldiers using WIN-T because, as they move across the varied terrain of the battlefield, their network access could at any time be provided through third-generation cellular, 802.11 wireless local-area networks, and satellite data transmissions. If their mobile data devices were required to give up their IP address each time they switched from one part of the network to another, the network would drop them.
Mobile IP use is not yet widespread, though organizations that have used it say its application in the government and military fields is obvious. In particular, companies such as Cisco can use it to write code that enables a router to completely control connections to the mobile network, rather than hosts sitting on the network that need special software, said Will Ivancic, a senior research engineer at the NASA Glenn Research Center.
"We've demonstrated the ability for a router to do that, both in the lab and out in the field," Ivancic said. "That's attractive from the military standpoint, because it's a relatively easy thing to secure since only the router needs to be protected."
As probably the first major use of mobile networking, WIN-T will demonstrate mobile technology's value for use on ships, in airplanes, for disaster relief "and for anything that has a network that is moving," Ivancic said.
Robinson is a freelance journalist based in Portland, Ore. He can be reached at firstname.lastname@example.org.
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The Army hopes the end result of the Warfighter Information Network-Tactical program will be a system that can deliver a steady data rate of 256 kilobits/sec to soldiers who could be standing still or in a vehicle bouncing across the battlefield at high speeds. The current mobile subscriber equipment tri-service tactical system can deliver bandwidth of only 16 kilobits/sec to 25 kilobits/sec to lower echelons, and even that is shared.
The final WIN-T system will employ a form of "ad hoc networking," said Ray Dolan, director of government markets for General Dynamics C4 Systems, in which the network can form and reform automatically on the fly.