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PodSnacks: Wavelength Division Multiplexing

Posted Wednesday, May 07, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2007q2/wdm.mp3
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)

Posted Monday, May 05, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2007q2/transmuxing.mp3
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

Posted Friday, May 02, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2007q2/ofdm.mp3
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)

Posted Thursday, May 01, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2008q2/niu.mp3
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

Posted Wednesday, April 30, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2007q2/cdma.mp3
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

Posted Monday, April 28, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2007q2/multiplexing.mp3
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

Posted Thursday, April 24, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2008q2/chained_layers.mp3
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

Posted Monday, April 21, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2007q2/hub.mp3
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: Asymmetric Digital Subscriber Line

Posted Monday, April 14, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2007q1/adsl.mp3
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)

Posted Thursday, April 10, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2008q2/dslam.mp3
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

Posted Tuesday, April 08, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2008q2/optical_network.mp3
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)

Posted Thursday, April 03, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2008q2/dsl.mp3
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: Synchronous Optical Network (SONET)

Posted Friday, March 28, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2007q1/sonet.mp3
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...

PodSnacks: Data Over Cable Service Interface Specification (DOCSIS)

Posted Thursday, March 27, 2008 6:00 PM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2008q1/docsis.mp3
The title of our PodSnack for today is a mouthful, but the concept is not so complex. When the cable companies decided to use their video networks to deliver other services, they needed new technology. Specifically, they needed the protocols and equipment Read More...

PodSnack: Circuit Switching

Posted Thursday, February 14, 2008 6:00 AM by mgilbert :: 0 Comments
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Attachment(s): http://podcast.hill-vt.com/podsnacks/2008q1/circuit_switching.mp3
Back to basics. I can't believe that I have never recorded a PodSnack about something so fundamental as circuit switching . Circuit switched networks are far from gone, although lately more and more emphasis has gone to packet switched networks. But Read More...
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