Ivan Pepelnjak
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Ivan Pepelnjak
ntopng Deep Dive with Luca Deri on Software Gone Wild
PF_RING is a great open-source project that enables extremely fast packet processing on x86 servers, so I was more than delighted when Paolo Lucente of the pmacct fame introduced me to Luca Deri, the author of PF_RING.
When we started chatting, we couldn’t resist mentioning ntopng, another open-source project Luca is working on.
Read more ...More Layer-2 Misconceptions
My “What Is Layer-2 and Why Do You Need It?” blog post generated numerous replies, including this one:
Pretend you are a device receiving a stream of bits. After you receive some inter-frame spacing bits, whatever comes next is the 2nd layer; whether that is Ethernet, native IP, CLNS/CLNP, whatever.
Not exactly. IP (or CLNS or CLNP) is always a layer-3 protocol regardless of where in the frame it happens to be, and some layer-2 protocols have no header (apart from inter-frame spacing and start-of-frame indicator).
Read more ...New Webinar: vSphere 6 Networking Deep Dive
The VMware Networking Deep Dive webinar was getting pretty old and outdated, but I always managed to get an excuse to postpone its refresh – first it was lack of new features in vSphere releases, then bad timing (doesn’t make sense to do a refresh in June with new release coming out in August), then lack of documentation (vSphere 6 was announced in August 2014; the documentation appeared in March 2015).
Read more ...Article: Is NFV Relevant for Enterprise Networks?
Network Computing recently published my “Yes, NFV Is Important For The Enterprise” article. Short summary: NFV is (like BGP and MPLS) yet another technology that is considered applicable only to service provider networks but makes great sense in some enterprise contexts.
I’ll talk about enterprise aspects of NFV at Interop Las Vegas, and describe some NFV technical details and typical use cases in an upcoming webinar.
IPv6 is 20 years old
An interesting message appeared on v6ops mailing list a few days ago: the first interconnect between independent IPv6 implementations was established 20 years ago. No wonder some youngsters who don't know any better treat this venerable protocol like a modem and ignore it in favor of IPv4 ;)Video: IPv6 Myths and Reality
I was talking and writing about IPv6 myths for years, but like any good myth they tend to be pretty robust. Unfortunately, as I explained in the IPv6 Myths and Reality part of IPv6 High Availability Strategies webinar, the reality seems pretty bleak: all we got are longer addresses, half-baked protocols, unsolved challenges, and heaps of confusion.
What Is Layer-2 and Why Do We Need It?
I’m constantly ranting against large layer-2 domains; recently going as far as saying “we don’t really need all that stuff.” Unfortunately, the IP+Ethernet mentality is so deeply ingrained in every networking engineer’s mind that we rarely ever stop to question its validity.
Let’s fix that and start with the fundamental question: What is Layer-2?
Read more ...Arista EOS Available on Whitebox Switches
A few months ago Gigamon did the right thing: they figured out that their true value lies not in the hardware boxes, but in the software running on them, and decided to start offering their GigaVUE-OS on whitebox switches.
So far, Arista is the only other networking vendor that figured out it doesn't make sense to resist the tide - Arista EOS is now available on Open Compute Networking whitebox switches.
Update 2015-04-02: If you followed the links in this blog post, you probably figured out that it’s an April Fools’ one. However, that’s not the end of the story…
Read more ...Video: Automating Network Security
The video of my Automating Network Security talk @ Troopers 15 has been published on YouTube. They used fixed camera and the slides are a bit hard to read; you’ll find a better copy of the slide deck on my content web site.
For a bit of fun, turn on closed captions (CC) – public cloud became public lout.
Too Many Details Can Hurt You (or Why You Need the Fundamentals First)
The IPv6 Security Summit at the Troopers conference always has a few awesome IPv6 presentations (many people claim Troopers is the conference to attend if you’re serious about IPv6), and this year was no exception. A day after the MLD bashing, Enno Rey delivered a great in-depth presentation on DHCPv6 features and shortcomings.
It seems the DHCPv6 intricacies presented in that talk were too much for some of the attendees – that afternoon I accidentally stumbled upon a visibly distressed gentleman who started our chat with “How could anyone expect us to deploy IPv6 in a production environment?”
Read more ...Common Misconceptions about SDN
Andrew Lerner, my favorite Gartner blogger, published a great article documenting common SDN misconceptions. Not surprisingly, they're pretty much in line with what I've been ranting about for the last few years (including Whitebox Switching Is not SDN). Enjoy!Microsegmentation in VMware NSX on Software Gone Wild
VM NIC firewalls have been around for years (they’re also the reason I got my first invitation to the awesome Troopers conference), but it sounds so much better when you call them Microsegmentation (not the one I talked about @ Troopers this year).
Marketing gimmicks aside, VMware NSX includes an interesting in-kernel stateful firewall, and Brad Hedlund was kind enough to explain the intricacies of that feature in Episode 27 of Software Gone Wild
MLD Considered Harmful
Multicast Listener Discovery (MLD) protocol is well hidden deep in the bowels of IPv6 protocol stack and most of us tend to gloss over it when we discuss IPv6 neighbor discovery process… until MLD raises its ugly head to bite an unsuspecting network administrator.
The problems with MLD are not new (and I wrote exhaustively about them a while ago), but it’s always nice to see other people raise awareness of broken IPv6 features like Enno Rey and his security team did during the IPv6 Security Summit (part of Troopers 15 conference).
Read more ...Availability Zones in Overlay Virtual Networks
Amazon Web Services was (AFAIK) one of the first products that introduced availability zones – islands of infrastructure that are isolated enough from each other to stop the propagation of failure or outage across their boundaries.
Not surprisingly, multiple availability zones shouldn’t rely on a central controller (as Amazon found out a few years back), and there are only few SDN controller vendors that are flexible enough to meet this requirement. For more details, watch the free Availability Zones video on my web site (part of Scaling Overlay Virtual Networking webinar).
Whitebox Switching: Follow the R&D Budget
A few weeks ago HP announced that they’d start selling branded whitebox (brite-box) switches, and as expected the industry press was immediately full of opinions. As always, it makes sense to follow the money (or, in this case, the R&D budget) to understand what’s going on behind the scenes.
Read more ...You must understand the fundamentals to be successful
I was speaking with a participant of the recent SDN event in Zurich after the presentations, and he made an interesting comment: whenever he experienced serious troubleshooting problems in his career, it was due to lack of understanding of networking fundamentals.
Read more ...Networking Field Day 9 Wrap-up on Software Gone Wild
A few days after the Networking Field Day 9 event Nick Buraglio organized a virtual meetup with Brandon Carroll, Brandon Mangold, Bob McCouch and myself, and we discussed the presentations from NEC, Cumulus, Cisco and Brocade. Nick recorded the conversation and so Episode 26 of Software Gone Wild was born.
IPv6 Cheat Sheet
Just in case you're new to IPv6 and struggle with the essentials: here's an excellent cheat sheet by Jeff Carrell… and don't forget to check the amazing Cheat Sheet Library @ packetlife.net.Presentation: Automating Network Security
The fantastic Troopers 15 conference is in full swing… and I’m done with the presentations ;) The last talk I had during the conference focused on automating network security. The slides are already online; I’ll add the link to the recording when they upload the videos.
Evaluation Guide: Encryptors for Metro and Carrier Ethernet
Christoph Jaggi, the author of Metro Ethernet and Carrier Ethernet Encryption Market Overview published an awesome follow-up document: an evaluation guide that lists most of the gotchas one has to be aware of when considering encryption gear, from deployment scenarios, network overhead and key exchange details to operational considerations. If you have to deal with any aspect of network encryption, this document is a must-read.