Windows Vista Not Playing Well with IPv6

Early adopters of Microsoft's new OS report problems with its implementation of a long-anticipated upgrade to the 'Net's primary protocol.

Carolyn Duffy Marsan, Network World

Early adopters of Microsoft's new Vista operating system are reporting problems with its implementation of IPv6, a long-anticipated upgrade to the Internet's primary protocol.

IPv6 supports a 128-bit addressing scheme, which lets it support an order-of-magnitude more devices that are directly connected to the Internet than its predecessor, IPv4. IPv6 also has autoconfiguration, end-to-end security and other enhancements.

Vista supports IPv6 by default. Vista runs a single-stack, dual-IP-layer architecture, which means it is IPv4- and IPv6-capable out of the box. It supports tunneling of IPv6 traffic over an IPv4 backbone and includes IPSec that works for both IPv4 and IPv6.

Network management software vendors and users are reporting problems with Vista's IPv6 implementation.

"Vista is showing some serious deficiencies around IPv6 and IPv4 insofar as their compliance or the transparency of their compliance around IP behaviors," says Loki Jorgenson, chief scientist for Apparent Networks, a provider of network assessment and optimization tools.

"For example, Vista doesn't expose any of the [Internet Control Message Protocol] errors to applications running on Vista," Jorgenson says. "The application can't get access to that message, and subsequently all it sees is that the network connection is not working. This is a big challenge for us around Vista. It's not clear at all why IPv6 isn't properly supported in this regard."

Duane Murphy, president of Managed Information Services in Long Beach, Calif., says he has experienced problems with Vista's IPv6 implementation on the networks he runs for law firms. Murphy used Network Instruments' Observer 12 application, which supports IPv6, to isolate Vista's IPv6 problems.

"We are seeing a number of applications that are IP-based that do not like the addressing scheme of IPv6," Murphy says. "We will send a print job to an IP-based printer, and the print job becomes corrupted. We're seeing this with Window's Vista machines. When IPv6 is installed, this happens without fail. As soon as we remove IPv6, all of our printer functions return to normal."

Murphy says the printing problem has cropped up on 45 Dell Latitudes and Dimensions running Vista Business or Vista Ultimate.

"We're also seeing loss of network connections on IP when you have both IPv6 and IPv4 loaded on the same machine with an IPv4-based network," Murphy says. "As soon as we remove IPv6, we suddenly have connectivity to the rest of the local workstations."

Murphy says he believes the problems stem from Vista's IPv6 implementation.

"We are connecting Observer to the monitoring port of a Cisco or HP switch, which allows us to monitor all the traffic across the network," Murphy says. "We figure out the name of each workstation, then we do a protocol analysis to figure out what protocols are running across the network. Once we do the protocol analysis, we can drill down on IPv6 and figure out what's wrong."

Murphy says he is recommending that his clients remove IPv6 from their Vista workstations.

"We are asking them to remove IPv6 on their new workstations until they are ready to move their entire network to IPv6," Murphy says. "This is something that needs to be brought to the attention of network managers from a troubleshooting standpoint. For the first three networks where we saw this, it took us almost six hours per network to figure out what was going on."

Microsoft says it is difficult to comment on the problems Murphy has faced with Vista's IPv6 implementation but the company has taken steps to address these types of compatibility issues.

"We recognize that not all applications and drivers were up to date by launch and that there have been some compatibility issues as a result," says Ian Hameroff, senior product manager with Windows Server Networking. "But we also know that Windows Vista is the highest-quality, most secure and most broadly supported operating system we've ever released."

Hameroff adds that Microsoft is running an IPv6 network and "to my knowledge has not experienced these types of issues" that Murphy describes. "We would welcome feedback from these vendors and are here to help."

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