Ivan Pepelnjak

Author Archives: Ivan Pepelnjak

The Cost of Networking Has Not Declined

One of the common taglines parroted by SDN aficionados goes along the lines of “The cost to acquire and manage server and storage architectures has declined over time while networking stays stubbornly expensive.” (I took it straight from an anonymous blog comment).

Let’s see how well it matches reality.

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Getting Started in the Mobile World

Got this challenge from one of my readers:

I've recently changed jobs and I am currently working for a telco. The problem is that I have no idea of what they are talking about when they mention SGSN, GGSN, Gi, Gn, etc... I only know routing and switching stuff :(.

Obviously he tried to search for information and failed.

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Source Code Is Not Standards

One of the oft-repeated messages of the Software-Defined Pundits is “Standard bodies are broken, (open) source code is king”… and I’d guess that anyone who was too idealistic before being exposed to how the sausage is being made within IETF has no problems agreeing with them. However…

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Questions about Network Automation Workshop

Marcel Reuter sent me a few questions about my upcoming Network Automation workshop. You might find them interesting, so here they are:

We have a lab with virtual IOS-XE, IOS-XR and Junos (vMX) router. I would like to learn how to provisioning the Lab router.

Covered in the workshop. I’m focusing on vIOS (which is pretty close to IOS Classic and IOS-XE) and Nexus OS because that’s what I can get up and running quickly in VIRL.

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Do We Still Need OSPF Areas and Summarization?

One of my ExpertExpress design discussions focused on WAN network design and the need for OSPF areas and summarization (the customer had random addressing and the engineers wondered whether it makes sense to renumber the network to get better summarization).

I was struggling with the question of whether we still need OSPF areas and summarization in 2016 for a long time. Here are my thoughts on the topic; please share yours in the comments.

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Using BGP in Leaf-and-Spine Fabrics

In the Leaf-and-Spine Fabric Designs webinar series we started with the simplest possible design: non-redundant server connectivity with bridging within a ToR switch and routing across the fabric.

After I explained the basics (including routing protocol selection, route summarization, link aggregation and addressing guidelines), Dinesh Dutt described how network architects use BGP when building leaf-and-spine fabrics.

Planning for Migration into the Cloud?

One of my readers sent me this question:

Have you written something about assessment and planning for migration of traditional in-premise data center network to private or public cloud? There would be hundreds of things to check during assessment and then plan accordingly.

Academically, that’s a wrong way of approaching the problem.

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Network Automation in Enterprise environments: pipe dream or reality?

When I talk about network automation with enterprise engineers I usually get responses along the lines of “That’s interesting, but it will never happen in my organization. That’s what startups or cloud providers do.

They couldn’t be more wrong: Thomas Wacker from UBS (one of the top 20 global financial services companies in case you don’t recognize the name) will describe how UBS uses network automation in new data center deployments during our Network Automation DIGS SDN event on September 1st, and we’ll spend the rest of the afternoon focusing on how you could get started and what your first network automation project should be.

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