IPv6 and SPAM Filtering

Service providers across the globe have warned that the transition to IPv6 will prove to be a hurdle towards filtering of SPAM.

As the IPv4 address space is nearing exhaustion, it was imperative to adopt the IPv6 addressing scheme to accommodate the ever increasing number of hosts that need to be online.

With the adoption of IPv6, more and more hosts will be able to have a unique public Internet address.

But this brings about a distinct and unique issue wherein the security service providers across the world use IPv4 IP address as the differentiating factor between good IP addresses and bad IP addresses that are known to send SPAM.

Blacklisting is the main technology behind SPAM blocking and with the introduction and adoption of IPv6, this scheme of SPAM filtering is under danger.

Stuart Paton who is a senior solutions architect at Cloudmark, advises that the adoption of IPv6 will result into the inability of the current email security systems to handle such traffic and hence will soon become overloaded and if new mechanisms are not envisaged soon and implementation is not figured out, there will be real danger to these security systems.

Along with SPAM filtering solutions, many other security services use IPv4 address as a means to identifying and blacklisting Denial of Service (DoS) attack sources, click jacking frauds, etc.

The reason security service providers and ISPs are worried about this fact is that in IPv6 each host on the Internet can have a unique IP address and keeping a track of such a vase address space is going to be an overwhelming task.

The reason behind this is that because of such a large address space in IPv6, spammers can effectively send out only a single SPAM through each IPv6 address and this would not flag as a SPAM activity on the security service provider’s honeypots.

Cloumark advises that there is a way out of this situation which would need to adopt a step-by-step approach.

Initially ISPs do not need to receive emails from an IPv6 host except for their own customers that are known to send such emails.

This particular approach would allow for a easy migration and will offer some level of business continuity to companies and organization that have already migrated to IPv6.

Paul wood who was an anti-spam expert with Message Labs (now Symantec cloud) confirms the fact that security service providers across the globe are not leaving out the idea of applying tough controls on mails from IPv6 hosts and networks.

Paul is of the opinion that until and unless necessary the ISPs shouldn’t accept emails unless they have been established as coming from trusted source.

Wood is of the vote that even though the spam filtering would prove to be a nightmare to some extent given the fact that IPv6 is getting adopted across the globe, the spammers would be having a tougher arena to cope up with as the possibilities of open relay servers would start decreasing.

Even though the address space is large, spammers would have the same issues that ISP would be facing and not having the technology that ISP will have scalability with IPv6 for spammers would have a diminishing effect on the returns.

Even though companies across the world are facing the dilemma whether to adopt IPv6 scheme or not, many experts believe that still about 40 to 50% of the IPv4 address space is unused and IPv4 address space is here to stay a lot longer than assumed.