Running an NT-based network on the USS Carl Vinson
The USS Carl Vinson (CVN 70) is a 95,000-ton, nuclear-powered aircraft
carrier in the US Navy. As part of the Navy's Pacific Fleet with home port at
the Puget Sound Naval Shipyard in Bremerton, Washington, the ship is home to
6000 personnel, carries 80 aircraft, and has one of the world's largest
floating LANs.
"Keeping this baby going is quite a job," laughs LAN
manager William T. Bowley, a data processing technician first class aboard the
Vinson. The "baby" is the Gold Eagle LAN, a Windows NT network
supporting about 600 Windows for Workgroups, Windows 95, and NT Workstation
clients. All users can access some version of Microsoft Office. All shipboard
personnel who need to keep in touch with the ship's chain of command have
systems connected into the LAN. Division officers use their systems to receive
orders from their department heads and communicate those orders to subordinates.
The Navy also gathers important information affecting the administration of the
ship and uses the LAN to distribute this information.
The Vinson is using NT as part of the Navy's Information Technology for the
21st Century (IT-21) initiative. Admiral Archie Clemens, commander
in chief of the Pacific Fleet, first presented the IT-21 concept during a speech
in January 1997. The Navy designed IT-21 to consolidate and expand existing IS
programs while the Navy faces the problems of increasing workloads and
decreasing budgets. The initiative consists of a set of principles and standards
that the Navy will use in all future IS projects (for information about these
principles and standards, see the sidebar, "Information Technology for the 21st Century," page 200). One important standard is NT, which, with Microsoft Exchange, will be the backbone of a new Defense Department-wide Defense Messaging System. This system will eventually carry all classified and nonclassified messages throughout the Department of Defense.
"We were among the first to adopt NT," says Bowley. Before NT,
the Vinson ran a Novell network supporting about 150 users. After exploring
options with the Novell network, the ship's maintenance and material management
coordinator, Lt. Commander John Joyner, concluded that the Novell network fell
far short of what was needed. He persuaded the ship's chain of command to adopt
NT in February 1996. This decision had vision: The Pacific Fleet reached the
same conclusion the following year.
Migrating to NT
The NT implementation took about four months (for Technician Bowley's views
on implementing the Gold Eagle LAN, see the sidebar, "An Interview with William T. Bowley," page 201). Growing the ship's network was not easy. " The cabling in place was not really designed for any kind of modern network,"
says Bowley. The ship has a thickwire Ethernet backbone designed to support
several large multiuser computer systems, not a large number of networked
personal computers. Without amenities such as drop ceilings on the aircraft
carrier, running new cables would not be easy. Eventually, the IS team
redesigned the network topology. The Navy placed intelligent transceivers to
create several subnetworks and better route the network traffic.
"We have six main servers running a mixture of NT Server 3.51 and
Server 4.0," Bowley said. "We have two Compaq servers, a ProLiant 1500
and a ProLiant 5000; the rest of the machines we put together ourselves. Most of
these are at least 100MHz machines."
Making Messaging a Top Priority
Because letter mail can be a significant problem for ships on deployment,
the team tried to improve on ship-to-shore messaging. Waiting two weeks for mail
to travel from the US to a ship in the Persian Gulf is not uncommon. Exchange is
one of the central applications on the Gold Eagle LAN and a key standard in
IT-21. "All our clients use Exchange as their email, and all our clients
have Internet email, which is quite unusual on a Navy ship," Bowley said.
Not everyone on the ship has access to Internet email. "Accessing email
over the Internet requires a certain level of seniority, but the Gold Eagle LAN
provided more Internet capability to more users than on any other ship in the
Navy."
Every day, the Exchange server handles between 3000 and 7000 messages. In
24 hours, the crew typically transmits about 1000 messages off ship and receives
an equal number from land. To support all the messaging traffic, the Navy
replaced the Vinson's existing Exchange server, a homegrown 100MHz Pentium
server that had 64MB of RAM and 4GB of storage, with a new Compaq 200MHz Pentium
Pro server with 396MB of RAM and an 18GB RAID array.
"We're really proud of the new Exchange server because migrating from
Microsoft Mail to Microsoft Exchange during the middle of a Western Pacific/Persian Gulf deployment was quite interesting," laughs Bowley. "When
we were on deployment in the Persian Gulf, we were one of the few ships in the
Navy that maintained an Internet mail link with the US. To say that this benefit
was an incalculable morale boost would probably be an understatement," said
Bowley. The ship sent and received more than 5000 Internet messages a day while
in the Persian Gulf. In all, the Vinson processed nearly 1.2 million email
messages during deployment in the Gulf.
The upgrade plan called for migrating one department from MS Mail to
Exchange every week. The IS team delivered a set of upgrade instructions to all
users. Of course, not every user followed all the instructions as carefully as
Bowley would have liked. The team was able to handle some problems over the
phone and use tools such as Systems Management Server (SMS). However, many
problems required visiting various sites around the ship. The ship's vast size
and intense level of activity while deployed made for some long days. "If
you're a network administrator, you know what I mean. I think a lot of my gray
hair is the result of that migration," says Bowley.
While at sea, the Vinson's network communicates with the US via the CA 3
Challenge Athena satellite system. The ship routes communications through Hawaii
to Florida, and then to the rest of the country. The system performs well, and
routinely permits email to travel from the ship to its destination in two to
four hours.
At times during deployment in the Persian Gulf, the ship experienced
transmission rates of four minutes. "Sometimes, it was almost chat-like,"
said Bowley. "We had a very generous bandwidth allocation because the
ship's chain of command realized the importance of giving the crew the ability
to communicate with their families."
In addition to email access, Web access is important. The Navy wanted to
expand the network and provide more services, such as Web access. "I'd say
about 200 of our clients run Microsoft Internet Explorer or Netscape Navigator.
About 50 of those clients have complete Web access; the rest are restricted
through Microsoft Proxy Server," said Bowley. Users on the ship regularly
access Web sites such as USA Today, CNN, Navy Online, and The Bureau of Naval
Personnel. The Navy Personnel site is particularly important because it contains
the latest instructions, policies, and advancement exam results. "The news
sites were extremely popular while we were deployed to the Arabian Gulf as part
of Operation Desert Strike," reports Bowley. "The Web access permitted
the crew to keep in touch with current events as they were happening, and this
capability contributed very positively to morale."
Looking Ahead to the 21st Century
What's next for the Gold Eagle LAN? The Vinson's IS team is busy preparing
to migrate many clients to NT Workstation 4.0 with Office 97. They're also
deploying a corporate-style intranet aboard ship. Each department will have a
set of Web pages for instructions and information. The IS team will use Adobe
Acrobat and other Web publishing tools to create links to other pages on and off
ship. "One department has already created an Adobe-based chain of command,
important instructions, and standard operating procedures, all in hyperlinked
text with imbedded photographs," said Bowley.
The USS Carl Vinson is a strong case for the IT-21 concept because the ship
is deploying standard technology quickly and to great effect. NT has helped in
many areas. "For us, it was a quantum leap," says Bowley, "I
don't know how we did our jobs before."
I truly enjoyed Ryan Maley’s December 1997 article, “Case in Point: NT on the High Seas.” I guess most people don’t realize the size of an aircraft carrier; it’s a floating city.
I have one question: Table A notes that Bandwidth for IT-21 is asynchronous transfer mode (ATM) backbone with 100Mbps Ethernet to the desktop. Assuming that 100Mbps implies CAT 5 cable, wouldn’t the network be susceptible to electromagnetic interference (specifically, deliberate interference by the enemy)? I would have thought that fibre would be the specification in use.
--Charlie Willits, MCP
I think the IT-21 specifications are the minimum specifications. Remember, IT-21 is designed for use throughout the Navy, including some very old facilities and ships. Adding fibre to some of these sites might be cost prohibitive. The military is probably more worried about RFI/EMI interference on equipment. Interference might interrupt the use of wire, but it won’t physically damage it. The same is not true for equipment such as routers or computers.
I agree with you about fibre. I’m sure as new ships and facilities are built, some kind of fibre will be the standard.
--Ryan J. Maley