Author: Brent Salisbury

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

[fancy_header3 variation=”slategrey”]Juniper and Cisco Comparisons of RIB, LIB, FIB and LFIB Tables[/fancy_header3] A quick overview before we start: [fancy_list style=”circle_arrow” variation=”slategrey”] RIBs maintain the network topologies and routing tables for each protocol. This would include many routes going to the same destination prefix. FIBs are the best route from the possibly many protocols in the… Continue reading Juniper and Cisco Comparisons of RIB, LIB, FIB and LFIB Tables

Use case for MPLS in the Enterprise for PCI Compliance

[fancy_header3 variation=”orange”] Use case for MPLS in the Enterprise for PCI Compliance[/fancy_header3] MPLS is today’s only form of scalable network virtualization we have for now. I personally think the promise of something called SDN will move into that space soon but until then, we need network virtualization. PCI is a joke. It is a racket… Continue reading Use case for MPLS in the Enterprise for PCI Compliance

Basic MPLS/VPN with Cisco IOS

[fancy_header3 variation=”steelblue”]Basic MPLS/VPN with Cisco IOS[/fancy_header3] This is a quick tutorial for basic MPLS/VPN with Cisco IOS configuration. The tutorial exemplifies basic PE to P to PE configuration on three Cisco 7200s running in GNS3 with IOS. R2 is configured as a route reflector P node and R4, R6 and R3 are PE node route reflector… Continue reading Basic MPLS/VPN with Cisco IOS

How Headers Encapsulate in the OSI stack

[fancy_header3 variation=”slategrey”]How Headers Encapsulate in the OSI stack[/fancy_header3] 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… Continue reading How Headers Encapsulate in the OSI stack

How I Learned to Hate the DCI

How I Learned to Hate the DCI: Layer 2 data center interconnects (DCI) is still alive and well. I blame VMware with vMotion and now every other Hypervisor vendor on the planet. Live workload migration is certainly vital to most operations. The further up the stack that happens the more flexibility you have with choosing more layers beneath… Continue reading How I Learned to Hate the DCI

What are Ethernet, IP and TCP Headers in Wireshark Captures

[fancy_header3 variation=”orange”]What are Ethernet, IP and TCP Headers in Wireshark Captures[/fancy_header3] 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… Continue reading What are Ethernet, IP and TCP Headers in Wireshark Captures

Why the NOS will decouple

Over the next couple of years some of us expect the networking industry to have some fairly significant changes. There are really two options: A distributed approach we have today or a controller based centralized model. We  have today just that, autonomous devices building adjacencies to one another, exchanging what it hopes are the best healthy paths… Continue reading Why the NOS will decouple

OTV configuration notes

Quick notes on OTV. I have not put this on lab gear yet so there may be typos. It does require licensing so make sure you have that budgeted, if not its a 20kish surprise which sucks.

#The Overlay interface ID (int overlay1) must match at both sites. A Vlan can only be assigned to… Continue reading OTV configuration notes