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Where’s My IPv6 Prefix? Part One

In a previous blog series about interfacing with your ISP, I mentioned tools that Internet Service Providers (ISPs) have, such as looking glasses and route servers, that can be used to verify their policies.  In this blog post, I want to examine some of those tools, but primarily I want to show how prefixes are propagating across the Internet. 

The question of prefix propagation comes up often when discussing how to develop an IPv6 address plan.  What happens if an organization gets Provider Independent (PI) space from a registry and then tries to advertise that prefix, or a smaller portion of that prefix, in a different region?  Will ISPs in that region filter the non-regional prefix?  Will they let the aggregate pass, but not the more specific prefixes? Read More »

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Making a Secure Transition to IPv6

Moving your network from IPv4 to IPv6 can be risky if you don’t close security holes

In February 2011, the last blocks of IPv4 Internet addresses were allocated, highlighting the need for organizations everywhere to plan their transition to IPv6, the next generation Internet protocol. Because the move to IPv6 is happening gradually, applications will support both Internet protocols for some time—and so must your network. During the transition from IPv4 to IPv6 your network could become vulnerable to new security risks, so it’s critical that you phase in the new protocol as securely as possible.

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