How much remaining IPv4 address space is “dirty?
” One topic that’s coming up in the IPv6 community is the prevalence of “dirty” IPv4 address space, which refers to unallocated prefixes that are used by various organisations to number their internal networks. Marc Blanchet, an IPv6 expert with consultancy Viagenie, says that of 24 unallocated prefixes he reviewed, 22 were “dirty” and only two were “clean.” The worry is that if a network operator starts broadcasting one of these “dirty” IPv4 prefixes, users will be shut off from sites and networks that use that prefix internally. The issue is important given that the Internet is expected to run out of IPv4 address space by 2012. The regional Internet registries said in January that less than 10% of IPv4 addresses remain unallocated. Sweden: Not as secure as you think. Sweden has been considered a leader in DNS security since 2006, when it became the first country to support DNS Security Extensions (DNSSEC) on .se, its country code top-level domain. DNSSEC prevents hackers from redirec
