TAG | IPv6
0 Comments | Posted by Enno Rey
Some readers will probably be aware that we are amongst the proponents of a quite strict stance when it comes to filtering IPv6 packets with (certain) Extension Headers and/or fragmentation, because those can be the source of many security problems (as laid out here, here or here). Actually I still think it was a very good idea of, amongst others, Randy Bush and Ron Bonica to suggest the deprecation of IPv6 fragmentation in the IETF.
On the other hand there are voices arguing that fragmented IPv6 packets will be needed in some cases, namely DNS[SEC]-related ones.
In this post I will discuss some details of this debate (taking place in many circles, incl. this thread on the ipv6-hackers mailing list which, btw, you should subscribe to). (more…)
The Strange Case of $SOME_SOFTWARE Adding an IPv6 Extension Header, and an Internet Router Dropping Them
0 Comments | Posted by Enno Rey
Last week Christopher and I were the instructors of an IPv6 workshop. In this one we usually build a lab with the participants incl. a variety of routed segments and native IPv6 Internet access. Once the latter part is implemented people start poking around and surfing the Internet from their laptops, not least to find out which sites they can actually reach from an v6-only network (please note that actually there are many).
On Saturday last week I had the pleasure of delivering a workshop on IPv6 networking at the MRMCD2015 conference in Darmstadt, Germany. It goes without saying that the atmosphere was quite amicable; as usual at CCC-related events. What definitely impressed me the most was the diversity of the audience. There were around thirty attendees representing several age groups and all with seemingly differing backgrounds.
When we wrote our initial blogpost regarding the evasion of Cisco ACLs by (Ab)Using IPv6, where we described (known to Cisco) cases of Access Control Lists (ACL) circumvention, we also suggested some mitigation techniques including the blocking of some (if not all) IPv6 Extension Headers.
Almost a month later, we got a comment from Matej Gregr that, even if the ACLs of certain Cisco Switches are configured to block IPv6 Extension headers like Hop-by-Hop or Destination Options headers, this does not actually happen/work as expected. Of course this made us re-visit the lab in the interim ;-).
I recently had the pleasure to join the 64th NANOG (North American Network Operators’ Group) meeting in San Francisco, which can be understood as one of the largest Internet engineering conferences at all. It takes place three times a year at different locations in North America.
What I personally like about NANOG is its strong collaborative and cooperative character. It is not about single persons and also not too much about spectacular projects but more about discussing technologies, ideas, challenges and numbers. Every talk has a comparatively large time slot reserved for discussion, which is often more than fully used. Discussion is typically actively focused and is more time-consuming (and even more relevant) than the talk itself. Which often is intended by the community. The climate of discussion is almost always impressively polite and constructive, even for controversially discussed topics.
In the course of a customer project I recently documented some thoughts and general objectives of IPv6 address planning, expanding on stuff I wrote a while ago in the series on “Address Plan Considerations”. An excerpt of that (newer) document can be found here. Due to the context it originates from it’s in German, still I hope it’s useful for some readers.
If you’re interested in the topic it might be a good idea to listen to Tom Coffeen‘s talk at the upcoming IPv6 Business Conference, too.
Everybody have a great day
Scott Hogg recently (in his post “Holding IPv6 Neighbor Discovery to a Higher Standard of Security“) gave the following answer:
“The security of IPv4 is roughly equivalent to IPv6. So why do we expect more from IPv6?”
While I highly value Scott’s IPv6 expertise – not least because I learned a lot about IPv6 security from the book on the topic he wrote together with Eric Vyncke – I strongly disagree with his statement, mainly with the first part. In this post I will lay out why I think that IPv6 is actually less secure than IPv4.
0 Comments | Posted by Niki Vonderwell
Welcome to the third edition of “Beyond the Thunderdome: A Review of TROOPERS15”. The focus today is on IPv6 and Data Center Networks, so kick back and enjoy the following talks and videos. And as always, check out our website www.troopers.de for details on TROOPERS16 March 14-18, 2016. (more…)
IPv6 is often called a “complex protocol”, not least by myself (for example in my keynote to the IPv6 Security Summit 2014). In this post I want to have a quick look at three questions:
– Can IPv6 be considered a “complex protocol”?
– Is it “more complex” than IPv4?
– Can we expect IPv6 networks to be “complex networks”?