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PodSnack: Static Route

We now return to one of my personal favorites: routing . Today we look at a specific type of route called the static route . Although it sounds rather inflexible, it turns out this type of route is fairly common, and plays some important roles in packet Read More...

PodSnacks: Routing Table

We've had several PodSnacks where we've made reference to something called the routing table . It's time we take a few moments and talk about this function, which is present in all routers and even in your desktop or laptop computer, assuming Read More...

PodSnacks: Default Route

Yet another basic concept, this one related to routing : the default route , also known as the default gateway or gateway of last resort . This is an important concept in routing. The Internet is a vast internetwork with millions of attached networks. Read More...

PodSnacks: Multiprotocol Label Switching (MPLS)

Well, we've been threatening to do this for a while, so today is MPLS day. Tune in as Michel explains the basic concepts. You can listen to (or download) the PodSnack by clicking here , or you can use the Flash player below. If you have an idea or Read More...

PodSnacks: Internet Control Message Protocol (ICMP)

Did you know that IP talks to itself? In many instances, when something goes wrong inside an IP network, there are small control messages generated that provide information about what happened. The same protocol that accomplishes this can also be used Read More...

PodSnacks: Datagram Networks

Some time ago, Mark gave you a run down of the concept of a virtual circuit . I suppose it's long past time we complete the matched set, so today, Paul will tell you about the other type of packet network, the datagram network. You can listen to (or Read More...

PodSnacks: Enhanced Interior Gateway Routing Protocol (EIGRP)

Our series on routing protocols concludes as we explore a hybrid routing protocol from Cisco. Michel takes you through a description of the Enhanced Interior Gateway Routing Protocol . You can listen to (or download) the PodSnack by clicking here , or Read More...

PodSnacks: Open Shortest Path First (OSPF)

Our series on routing protocols continues as we explore a link state routing protocol. Today, Michel and Trevor give you a fairly solid description of the Open Shortest Path First . You can listen to (or download) the PodSnack by clicking here , or you Read More...

PodSnacks: Routing Information Protocol (RIP)

In our continuing series on routing protocols , we move on to a vintage distance vector routing protocol. Today, Michel and Trevor give you a fairly solid description of the Routing Information Protocol . You can listen to (or download) the PodSnack by Read More...

PodSnacks: Border Gateway Protocol (BGP)

Recently, Mark and Trevor gave you definitions of interior and exterior routing protocols . We then looked at two broad classes of routing protocols: distance vector and link state . Today, Michel and Trevor give you a high-level description of the exterior Read More...

PodSnacks: Link State Routing Protocols (LSRP)

Last Friday, in our continuing series on routing protocols , we discussed distance vector routing protocols . The second major class of routing protocols is the link state routing protocol . Today, Michel and Trevor are going to talk to you about this Read More...

PodSnacks: Distance Vector Routing Protocols (DVRP)

In our continuing series on routing protocols , we now shift to two broad classifications of routing protocols that are based on what the routing protocol includes in its update and where it sends that update. Today, Michel and Trevor are going to talk Read More...

PodSnacks: Exterior vs. Interior Gateway Protocols

Some time ago, we did a PodSnack on routing protocols . Since then, we've received a few requests to expand on various routing protocols, so we're going to set out, over the next few days, to classify routing protocols and then provider summaries Read More...

PodSnacks: Link State Database (LSDB)

Enough of the basics! For today, we're going to give the more technically oriented members of our audience a little something to chew on. Our topic today comes from the world of routing , specifically, OSPF . We're going to talk about a construct Read More...

PodSnacks: The Chained Layers

Back to the OSI Reference Model for a moment. You may sometimes hear reference to the chained_layers . This is a reference to the first three layers of the model, so named because chaining them together creates the fabric of an inter-network. In today's Read More...
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