Fundamentals

SDN, OpenFlow and OpenDaylight Updates and Recordings

Stop Cant Do It Sm

It’s been a busy few weeks in the SDN debate. I am posting some SDN updates from April along with some recordings from various events. The Open Networking Summit held its event. Only a few of the videos have posted so far. The keynotes and presentations that stuck out to me were, Rose Schooler from Intel, Bruce Davie from Nicira/Vmware, …

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Putting Together Provider Bridging, Provider Backbone Bridging, S-Tags and C-Tags

PBB1

Putting Together Provider Bridging, Provider Backbone Bridging, S-Tags and C-Tags: Understanding carrier bridging techniques is important, not just for provider operators, but also for engineers on the customer edge. When turning up or troubleshooting a circuit, carrier operators will ramble off C-tag and S-tag when many in the enterprise, are used to hearing Vlan ID in single tenancy deployments. More …

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OpenFlow: SDN Hybrid Deployment Strategies

Risk

This series of posts, has been focused on reviewing some practical OpenFlow SDN deployment strategies. Early SDN, will be hybrid networks and early niche applications to begin understanding how to integrate pockets of SDN, mitigate risks and most importantly understand the technology to properly scale solutions. If you try and put 5,000,000 access-lists into a kit that can only do 2,000 …

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OpenFlow: Coarse vs. Fine Flows

Flow Factory2

OpenFlow: Coarse vs. Fine Flows – This series of posts, is to shed light on some illogicalities surrounding the SDN discussion. I will highlight what I propose, will achieve performance and scale when implementing flow based forwarding designs. Soon these debates, will no longer be conceptual or limited deployments in only the hyper-scale networks, as more of us begin real-life implementations. …

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SDN OpenFlow Policy Abstractions

Flow Factory4

SDN OpenFlow Policy Abstractions : Abstraction layers are a fundamental principle in computer science. It is a core pillar in creating efficiencies through layered, modular scale. Proper abstraction layers are also where the networking train came off the tracks. Network operators program network devices using proprietary APIs one device at a time. In today’s networks, when we push policy to …

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The Control Plane, Data Plane and Forwarding Plane in Networks

Layered Planes

The Control Plane, Data Plane and Forwarding Plane in Networks is the heart core DNA in today’s networking hardware to move IP packets from A to Z. The Management plane is another vital component but also widely excepted as user to hardware interaction. These planes of operation are the building blocks of the layered architecture that networks have evolved to …

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The Best MPLS Lecture on the Net

All Stacks1

The Best MPLS Lecture on the Net: The title says it all. Professor Karandikar gives two amazing lectures on MPLS and MPLS-TE that most engineers should hope to know cold. I watch it probably once every few months. Not saying much for my memory these days. It is an amazing amount of material delivered very precisely. Great stuff! I added some …

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Ethernet Switch Fabric Cards

I was working with a buddy today about ethernet switch fabric cards in the nexus 7000 and not doing a very good job at explaining it, so I figured I would draw some pictures. The conversation was around how adding more fabric cards increases the bandwidth. I think some, myself included growing up on Catalyst 6500′s got accustomed to a …

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Juniper Default Routing Tables

Juniper 01

The first time I saw these I remember thinking what is going on here. It can be pretty foreign the first time someone sees it especially coming from Cisco IOS. The two CLIs wrap and abstract the underlying standardized frameworks pretty differently. I think it helps to decouple what the function of the table is before ever operating the gear. …

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Juniper and Cisco Comparisons of RIB, LIB, FIB and LFIB Tables

A quick overview before we start: It starts off with the ingress packet. As a packet comes into the Label Edge Router (LER) the Layer2 frame header will be examined and forwarded to the appropriate table, based on the Ethertype field to determine what protocol in payload of the Ethernet frame. The table interactions in principle are the same between …

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How Headers Encapsulate in the OSI stack

How Headers Encapsulate in the OSI stack: Part 2 of some refreshers. We send application data or payload by encapsulating or framing each layer within the previous layer. We looked at each one individually and now here is how they look when each layer is wrapped inside the previous layer.  Figure 1. Here is how application data gets passed to each …

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What are Ethernet, IP and TCP Headers in Wireshark Captures

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If I could go back in time when I was a n00b kid wanting to go from zero to a million in networking, the one thing I would change would be spending about 6 months on the fundamentals of networking headers and framing before ever touching a single peice of vendor gear. Ethernet, IP and Transport headers (L2-L4) are the …

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