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PodSnacks: Wavelength Division Multiplexing

We wrap up our multiplexing series with a quick look at wavelength division multiplexing (WDM). In today's episode, Michel and Mark noodle on the concept a bit. Over the next few days we will begin a series of PodSnacks based on requests from listeners. Read More...

PodSnacks: Transmultiplexing (Transmuxing)

Continuing with our multiplexing theme, today Trevor talks to you a bit about transmuxing . 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 request for a PodSnack topic, send Read More...

PodSnacks: Orthogonal Frequency Division Multiplexing

Our multiplexing theme continues. Recently, we talked about a multiplexing scheme found in wireless systems, called code division multiple access (CDMA). Today, Paul explains another multiplexing approach that is found in both wireless and wireline systems: Read More...

PodSnacks: Network Interface Unit (NIU)

OK, some of you apparently like the basics! So let's go back to them. Our topic today is a much used term, but one with a lot of variation in practice. The term is network interface unit (NIU). This is the place where the carrier's network touches Read More...

PodSnacks: Code Division Multiple Access

We recently talked about multiplexing in general. Today we focus on a specific form of multiplexing that is primarily found in wireless systems (although it can be (and is) also used in the HFC cable plant of a cable company. The technique is known as Read More...

PodSnack: Multiplexing

Let's go back to basics, at least at first. In today's PodSnack we're going to talk about multiplexing in general and in it's most basic forms. Then, in the coming days, we're going to explore other multiplexing-related issues. You 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...

PodSnack: Hub

Do you have a hub ? I suspect you probably don't. They're still around though. I was amazed, last Friday, when one of the kids in my son's Boy Scout troop walked in with an old Ethernet hub they use to network their Xboxs. And they're Read More...

PodSnacks: Analog

Back to basics! Paul and I recorded this PodSnack about the word " analog ." It's a term that surfaces all of the time. The word itself is fairly innocuous. In telecommunications, it refers to a communications system that uses a continuously Read More...

PodSnacks: Asymmetric Digital Subscriber Line

Since we've been talking a bit about DSL technologies, it seems a good time to focus in on one specific form of DSL: the one most commonly found. So today, Mark is going to give you a primer on Asymmetric Digital Subscriber Line (ADSL). You can listen Read More...

PodSnacks: Digital Subscriber Line Access Multiplexer (DSLAM)

We recently explored digital subscriber line (DSL). One important part of delivering DSL services to customers is a piece of equipment known as the DSL access multiplexer (DSLAM). In today's PodSnacks, I'll explore what this device is, what it Read More...

PodSnacks: Optical Network

In the past, we have looked at SONET . Since SONET stands for Synchronous Optical Network , one would be tempted to think we have already discussed optical networking, so there' nothing left to be said. The fact is, we haven't really talked about Read More...

PodSnacks: Digital Subscriber Line (DSL)

We spent some time on DOCSIS , so I suppose it's only fair to give a bit of equal time. The telephone companies don't have a lot of coaxial cable in the local loop . What they do have a lot of is twisted pair . Enter digital subscriber line (DSL). Read More...

PodSnacks: Graded-index vs. Stepped-index Multimode Fiber

We have done other PodSnacks on optical fiber . We've even discussed the difference between single-mode fiber and multimode fiber . Today we narrow the scope even further and distinguish between graded-index and stepped-index MMF. The difference lies Read More...

PodSnacks: Synchronous Optical Network (SONET)

At the core of virtually every carrier and MSO's data and voice network sits a technology we have been using since 1984. By some estimates, over 99% of all of the voice and data traffic that touches a carrier or MSO network crosses a SONET facility Read More...
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