IPv6 (define) is coming and it's big business for companies such as Global Crossing and Computer Sciences Corporation.

The two companies have entered into an agreement that will see Global Crossing deploy IPv6 across the CSC network.

CSC will now make IPv6 services available to its customers in both government and commercial enterprises.

Financial terms of the deal were not disclosed, though Alan Rosenberg, vice president of partnership development at Global Crossing, noted that the deal is significant and the opportunity is very large, particularly in light of the looming federal deadline on IPv6.

The U.S. federal government has mandated that all government agencies be IPv6-capable by 2008.

"CSC partnered with Global Crossing to build a capability to test and evaluate IPv6 per future mandates that will require many of our customers to be IPv6-capable," Michael C. Palermo, director of CSC's enterprise network managed services, told internetnews.com.

"With this mandate looming, CSC's Enterprise Network Managed Services Center of Excellence took a proactive stance and built a test network with Global Crossing to enable testing and evaluation of applications and network appliances."

Global Crossing is providing the WAN connectivity with service that supports both IPv6 and the existing IPv4.

Rosenberg noted that the fact that Global Crossing supports both IP versions on the same physical connection should help to ease migration.

Beyond just trying to help U.S. federal agencies to comply with the 2008 mandate, the need for IPv6 solutions exists in both federal and commercial markets, according to Rosenberg.

One of the most obvious benefits to IPv6 is that it dramatically expands the available pool if IP addresses. IPv4 supports 4.3 billion (4.3x10⁹) addresses while IPv6 support a lot more (3.4x10³⁸) addresses.

The address shortage isn't as much a problem in the U.S. but is particularly important in the geographical areas where the IPv4 address space is limited.

Rosenberg noted that in China for example there is only one IPv4 address for every eight people.

The need for IPv6 is ultimately inevitable as populations grow and more devices become Internet-aware.

"We all remember when we only had to dial a seven-digit or less number to make a telephone call locally," CSC's Palermo said.

"Now we have to include an area code in our telephony dialing. This is synonymous to IPv4 to IPv6. We are running out of IP addresses globally. That is the reason for change."

IPv6 presents a number of challenges. Among them are the costs of transition. A 2005 report pegged the cost of U.S. transition to IPv6 at $75 billion.

CSC's Palermo noted that address management will also be an issue and that many hardware and software applications that people are used to working with in IPv4 environments will not operate under IPv6, including operating systems, network management systems, Active Directory, intrusion detection systems and many others.

Rosenberg noted that one of the critical elements in Global Crossing's network is the ability to handle the increased addressability that IPv6 provides.

It's all part of a multi-billion-dollar investment that Global Crossing has made into IPv6 infrastructure.

Rosenberg explained that the company wasn't going to rely on any one hardware vendor for IPv6 equipment.

As with IPv4 equipment, Cisco and Juniper Networks are the industry leaders.

Juniper is being deployed in China in what is arguably already the world's largest IPv6 network.

"We have a combination of platforms," Rosenberg said. "We have Juniper, we have Cisco and we work with both providers.

"We obviously understand that IPv6 isn't specific to one vendor and is something that needs to be well-embraced and distributed through the industry, so we think it important to work with both providers."