Blog Posts in August 2017
My friend Christoph Jaggi published new versions of his Metro- and Carrier Ethernet Encryptor documents:
- Technology introduction, including an overview of encryption mechanisms, Carrier Ethernet connectivity models, typical deployments, and key management challenges.
- Market overview, including standards, control- and data plane considerations, key- and system management, and network integration.
A network engineer interested in attending the Building Network Automation Solutions online course sent me this question:
Does the course cover only Ansible, or does it also cover other automation tools like Python?
The course focuses on how you’d build a network automation solution. Selecting the best tool for the job is obviously one of the major challenges, and so one of the self-study modules describes various automation tools and where you could use them to build a full-blown solution.
Rich sent me a question about temporary traffic blackholing in networks where every router is running IGP (OSPF or IS-IS) and iBGP.
He started with a very simple network diagram:
A network architect working for a system integrator sent me a number of questions along the lines of “what would be an interesting alternative to pursuing another CCxE certification?”
One of the use cases we covered in Network Automation Use Cases webinar is a fully-automated data center fabric deployment. Dinesh Dutt (Cumulus Networks) started this section with an overview of challenges you might face in data center fabric deployments.
If you want to automate your fabric with Ansible, enroll into the Ansible for Networking Engineers course, or attend the Building Network Automation Solutions course if you want to get a broader view.
John Allspaw wrote an interesting blog post describing how he dealt with requests to introduce new technologies or design patterns. While he’s writing from the software development perspective, the ideas apply equally well to network architecture, so go and read what he has to say (and how he defines what engineering method is).
One of the engineers going through my Ansible for Networking Engineers online course sent me this question:
In the Introduction section, you mention a use case of upgrading software. Do you have an example playbook?
Unfortunately, I don’t. Upgrading software is one of those things that’s almost impossible to simulate in a virtual lab.
Eyvonne Sharp wrote an interesting blog post describing the challenges Cisco might have integrating Viptela acquisition, particularly the fact that Viptela has a software solution running on low-cost hardware.
Guess what… Cisco IOS also runs on low-cost hardware, it’s just that Cisco routers are sold as a software+hardware bundle masquerading as expensive hardware.
Some networking practitioners start their network automation journey with the Python or Ansible dilemma. Engineers and architects usually want to understand the bigger picture first, and figure out the potential showstoppers and roadblocks. One of them left this feedback on the Network Automation 101 webinar:
A must-have overview of fundamental Network Automation concepts. I wouldn't face an automation project without understanding these concepts first.
In mid-July dr. Olivier Bonaventure (one of the unsung networking heroes who’s always trying to address real-life problems instead of inventing unicorn solutions in search of a problem) sent an email to v6ops mailing list describing how they teach networking.
Short summary for differently-attentive:
Got this feedback from a network architect attending the Open Networking for Large-Scale Networks webinar:
I used the webinar when preparing for a meeting/discussion with a NOS SW-vendor. In the meeting, my knowledge was completely up-to-speed & I was on the level with the vendor in the discussion! :-)
Daniel Dib is setting up a networking career (from a down-to-earth engineer’s perspective) web site, and started populating it with numerous interviews with fellow networking engineers and architects (all of them well worth reading).
Here are my answers to his questions.
It’s amazing how long it can take to get some sanity into networking technologies. RFC 8212 specifies that a BGP router should not announce prefixes over EBGP until its routing policy has been explicitly configured. It took us only 22 years to get there…
For more technical details, read this email by Job Snijders.
Net neutrality is one of those topics that should never have existed, but of course it inevitably erupts every so often, so here we go…
Not so long ago Robert Graham published his anti-net-neutrality arguments which are (no surprise) not much different from what I wrote when I still cared about this argument (here, here, here and here). While I agree with his overall perspective, I completely disagree with his view of Comcast’s initial response to network congestion.
You wouldn’t believe it – after almost 22 years (yeah, it’s been that long since RFC 1883 was published), IPv6 became an Internet standard (RFC8200/STD86). No wonder some people claim IETF moves at glacial speed ;)
Speaking of IPv6, IETF and glacial speeds – there’s been a hilarious thread before Prague IETF meeting heatedly arguing whether the default WLAN SSID should be IPv6-only (+NAT64). Definitely worth reading (for the entertainment value) over a beer or two.