Let’s change everything - and cause no damage for the end users!

The current version of the Internet is up for a big overhaul. We have to change the whole infrastructure it runs on, the famous IP protocol. A lot of work needs to be done and it affects everyone that works with the infrastructure. The result of all the hard work? Everything will work exactly as before. Nothing gained for the end-user experience. That’s why very few are paying attention to IPv6 - it is very hard to tell the persons in charge of IT projects what the benefit is compared with upgrading all PCs to Windows 7 or installing that new spam filter for e-mail.

Internet telephony needs IPv6 peer-to-peer addressing

It is easy to explain the need for a unified address space using telephony as an example. The fact that all companies and homes use a private address space that can’t be reached from the outside doesn’t matter when it comes to the old-fashioned Internet applications. The web browser contacts a server on the Internet. The e-mail client contacts an e-mail server on the Internet. The IM/Presence application contacts a server on the Internet. Nothing needs to reach in. Until you start using peer-2-peer applications. And telephony is a very common p2p application.

• -”You know that you have a broadband router that use one IP address from the Internet, assigned to you by the provider?
• “- “Yes”
• - “Do you also know that the broadband router let’s all your devices on the inside share this address by setting up a private address range?”
• - “Yes”
• - “If you add an IP phone on the inside - do you want to be able to receive calls?”
• - “Yes”
• - “How do you think I can call your phone  directly, if we don’t share the address space?”
• - “I don’t know.”

With IPv6, true p2p Internet telephony will become possible. When we get rid of the need for NAT, network address translation, we can finally separate access and policy. With a unified address plan, every device on the net has the possibility of reaching every other device. Policys might prevent that and we implement the policy in firewall software in the systems or in dedicated systems.Currently, in order for a phone to work on the inside of a NAT, most implementations connect to a server on the Internet. In order for an incoming call to get through, the phone or the server keeps sending empty messages. As long as these messages are sent - occupying unneeded bandwidth and resources in the network - the NAT believes there’s a communication session going on and let the messages in.The NAT itself has no policy, it just checks if there’s a client-initiated session going on or not. As long as the NAT believes there’s a session, it will forward packets from the outside to the inside device. When you have an incoming call, the server can forward an alert to the phone and the phone will start ringing. The same setup is used if your organization has a PBX system on the inside and use a SIP trunk provider on the Internet.This solution is uses by a range of applications and are not unique in any way for IP telephony.  IPv6 will make it easier to enable true Internet telephony and other p2p applications, as long as your firewalls let it happen. (more…)

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