Learning to Ask Questions
One thing I’m often asked in email and in person is: why should I bother learning theory? After all, you don’t install SPF in your network; you install a router or switch, which you then configure OSPF or IS-IS on. The SPF algorithm is not exposed to the user, and does not seem to really have any impact on the operation of the network. Such internal functionality might be neat to know, but ultimately–who cares? Maybe it will be useful in some projected troubleshooting situation, but the key to effective troubleshooting is understanding the output of the device, rather than in understanding what the device is doing.
In other words, there is no reason to treat network devices as anything more than black boxes. You put some stuff in, other stuff comes out, and the vendor takes care of everything in the middle. I dealt with a related line of thinking in this video, but what about this black box argument? Do network engineers really need to know what goes on inside the vendor’s black box?
Let me anser this question with another question. Wen you shift to a new piece of hardware, how do you know what you are Continue reading
What is a Tunnel
It’s a bird! It’s a plane! It’s a… tunnel? In this video, I take on the age old question: what is a tunnel? Is it a protocol, or is it something else?
A glance back at the looking glass: Will IP really take over the world?
In 2003, the world of network engineering was far different than it is today. For instance, EIGRP was still being implemented on the basis of its ability to support multi-protocol routing. SONET, and other optical technologies, were just starting to come into their own, and all optical switching was just beginning to be considered for large scale deployment. What Hartley says of history holds true when looking back at what seems to be a former age: “The past is a foreign country; they do things differently there.”
In the midst of this change, the Association for Computing Machinery (the ACM) published a paper entitled “Will IP really take over the world (of communications)?” This paper, written during the ongoing discussion within the engineering community over whether packet switching or circuit switching is the “better” technology, provides a lot of insight into the thinking of the time. Specifically, as the author say, the belief that IP is better:
…is based on our collective belief that packet switching is inherently superior to circuit switching because of the efficiencies of statistical multiplexing, and the ability of IP to route around failures. It is widely assumed that IP is simpler than circuit Continue reading