Problems with removing NAT from a network

Leen Besselink leen at
Sat Jan 8 05:16:40 CST 2011

On 01/07/2011 03:57 AM, Matthew Kaufman wrote:
> On 1/6/2011 6:34 PM, Joel Jaeggli wrote:
>> On 1/6/11 5:48 PM, Owen DeLong wrote:
>>> Doesn't all of this become moot if Skype just develops a dual-stack
>>> capable client
>>> and servers?
>> Really, only some fraction of the supernodes and the login servers need
>> to be dual stack.
> Without revealing too much about the architecture, I can tell you that
> it would need to be a significant fraction of the supernodes (due to
> how node-supernode mapping works in these types of P2P systems), the
> relay nodes (not mentioned) *and* the login servers. Not all of which
> are deployed and controlled by Skype, of course, as recent press about
> the most recent outage has reiterated for those who didn't know.
> Matthew Kaufman
Hello Mr. Kaufman,

In the upcoming years, we will have no IPv6 in some places and badly
performing IPv4 (CGN, etc.) with working IPv6 in others.

If I was Skype I would make really sure that all my relay nodes and
login servers have IPv6 with enough bandwidth or can easily upgrade the
bandwidth where neede. And make sure atleast IPv6-client and
IPv6-servers communication works everywhere where there is IPv6.

Atleast get your servers and network ready with IPv6. Tell your
suppliers that if they don't have IPv6 by 'deadline' (you decide) you
will (have to) go somewhere else.

Because if you still have to deploy, test and fix IPv6 to your servers
when it turns out the transition workarounds you have created in
software don't work as well as you hoped then you will have a real
problem on your hands.

For your customers it is really easy. When Skype does not work, people
will jump ship where they can and maybe use Google Talk or whatever. I
hear they also have a similair service like SkypeOut ? Judging by the
amount of effort Google put in to making sure their network supports
IPv6, I wouldn't be surprised if Google Talk 'just works'. They might
even start including it with Google TV.

I suggest making sure you include both IPv4 and IPv6 addresses in your
protocol, maybe it needs to be extended. So that the client at the other
end can choose what IP-version to use. Or can try both. Maybe the
login-server can help to decide for the client. But those login servers
will need to have good IPv6 connectivity to be able to do so.

If you don't do these 2 things (maybe you already have I don't know) you
might find that your business will suffer.

I'm sorry if it sounds a bit like fear mongering, but to me it sounds
like common sense that if a business is not prepared when the
environment that business operates in changes and that business does not
adapt to the changes in time that business might suffer.

Have a nice weekend,

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