Using Big Tools for Small Problems

regrigerator-smart-car

BGP in the data center? And MPLS? Are you insane? Well, maybe, yes. But then again, I've been known to do a lot of crazy … [Read more...]

Video over Internet

Video_Drop

Couple days ago I made an interesting talk about Video Traffic over Internet. Sales engineer goes to company and he claims … [Read more...]

Anycast HSRP and Design Considerations

hsrp

HSRP is the first hop redundancy Cisco property protocol which allows a transparent failover of the first-hop gateway. Many … [Read more...]

HTIRW: The Business Side of DNS (2)

</a>continued from part 1 The top level server is either paid for by the domain owner (if they are managing the TLD … [Read more...]

HTIRW: The Business Side of DNS (1)

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So your host queries a DNS server to map the name to a location (an IP address), which sets off a chain of queries across a … [Read more...]

HTIRW: DNS Lookups

browser-lookup

Note: Some of this will be really basic for a lot of folks, but bear with me — in looking at the entire system as a system, … [Read more...]

HTIRW: Overview

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Okay, so we all know some little slice or another of the Internet. But how do all these slices really fit together? How does … [Read more...]

Windows ISATAP Client, Part 1

Last month I had the opportunity to work with a company to perform an IPv6 pilot.  There are a lot of elements to light up … [Read more...]

Cisco Internal VLAN Usage

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About a month ago I worked on an old CatOS switch. Working on this switch reminded me about some of the differences between … [Read more...]

Ordered FIB

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In a past post, we’ve discussed microloops in link state protocols. If we examine a small ring topology (if you come to my … [Read more...]

Secret CEF Attributes Part 6, The BGP Connection

In the first five parts of this series we covered all the steps necessary to distribute QoS and monitoring to a large … [Read more...]

Using Next Generation MVPN to optimize your MPLS core – Part 1

Intra-AS

Like many network engineers I have had difficulties with multicast, the logic is all messed up right!? The only … [Read more...]

Secret CEF Attributes, Part 5

So far we've explored some very cool features of CEF and the attributes we can push into the FIB to identify certain kinds of … [Read more...]

Secret CEF Attributes, Part 4

In Parts 1, Part 2 and Part 3 we saw we can use the CEF table to express all sorts of different QoS policies. In Part 4 we … [Read more...]

Out with the old, in with the new

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A few weeks ago I was asked to help a client turn up and move everything over to a new network. I have done this many times … [Read more...]