Show 43 – Microsoft Teredo is Crap

A shorter show this week as Greg gets ready to go to Interop in Las Vegas next week. We look at recent events and talk generally about network with Tom Hollingsworth, Brandon Carroll and Greg Ferro.

Amazon AWS outage.

People need to start realizing that just parking your infrastructure in the cloud doesn’t make it redundant. There is additional planning and design work. Network engineers and architects don’t just make this stuff up, as the people who undoubtedly lost their jobs because of this fiasco are now learning.

According to this post by Jeremy Gaddis, it would appear that a wayward engineer was attempting to upgrade IOS on a device and jumped the gun on downing another section of the network, triggering a waterfall of failure. A cautionary reminder that you can never anticipate the human element:

Sony Playstation Network

Playstation Network goes down and gets pwned. If you thought AWS was bad, Sony managed to exposed 77 million people in one shot. The whole backbone of their online distribution network went down and they couldn’t do anything about it. To add insult to injury, it appears customer data was readily available from the hack. As of today, there are approximately 2.2 million credit cards up for sale, all with the critical CVV codes. Compartmentalization, anyone?

IPv6 / IPv4 NAT – Hang our Heads in Shame

RFC 6146 – Stateful NAT64 and RFC 6147 – DNS64. I think there’s a lot of discussion around these two. It appears that someone is of the opinion that the transition from IPv4 to IPv6 won’t happen without a little hand holding. I think these people are the same ones that still take chewable vitamins. Yes, it’s a bitter pill but you had best get used to swallowing it.

IPv6 and Microsoft Teredo

  • Host to Host, Host to Router, Router to Router.
  • Teredo is Host to Host, relies on public gateways of someone elses/anyones servers
  • not HA
  • not reliable

Teredo is described in a Microsoft technical note –

Teredo uses what has become a relatively conventional approach to NAT traversal, using a simplified version of the STUN active probing approach to determine the type of NAT, and uses concepts of “clients”, “servers” and “relays”

The choice between the terms “transition” versus “coexistence” has engendered long philosophical debate. “Transition” carries the sense that one is going somewhere, while “coexistence” seems more like one is sitting somewhere. Historically with the IETF, “transition” has been the term of choice [RFC4213] [RFC5211], and the tools for interoperability have been called “transition mechanisms”. There is some perception or conventional wisdom that adoption of IPv6 is being impeded by the deficiency of tools to facilitate interoperability of nodes or networks that are constrained (in some way, fully or partially) from full operation in one of the address families. In addition, it is apparent that transition will involve a period of coexistence; the only real question is how long that will last.

Thus, coexistence is an integral part of the transition plan, not in conflict with it, but there will be a balancing act. It starts out being a way for early IPv6 adopters to easily exploit the bigger IPv4 Internet, and ends up being a way for late/never adopters to hang on with IPv4 (at their own expense, with minimal impact or visibility to the Internet). One way to look at solutions is that cost incentives (both monetary cost and the operational overhead for the end user) should encourage IPv6 and discourage IPv4. That way natural market forces will keep the transition moving — especially as the legacy IPv4-only stuff ages out of use. The end goal should not be to eliminate IPv4 by fiat, but rather render it redundant through ubiquitous IPv6 deployment. IPv4 may never go away completely, but rational plans should move the costs of maintaining IPv4 to those who insist on using it after wide adoption of IPv6.

Hosts / Guests

Tom Hollingsworth | Twitter: @NetworkingNerd

Brandon Carroll | Twitter: @brandoncarroll

and last, and the very least:

Greg Ferro| Twitter @etherealmind


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