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 And we're just going to finish this
 video with just some terminology.

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 Much of the terminology I've already
 discussed, so this will be just a

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 quick review. So in the multicast stream,
 we typically call it a stream.

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 That's your data like your voice or your
 video that's going out just into

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00:00:25,760 --> 00:00:27,260
 this multicast address.

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 We call that a multicast stream.

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00:00:28,760 --> 00:00:31,960
 You might also hear that referred
 to as a multicast channel.

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00:00:31,960 --> 00:00:33,960
 I've also seen it called
 that as well.

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00:00:33,960 --> 00:00:37,060
 So a multicast source, right?

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 That's the actual server that's generating
 the multicast packets.

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00:00:41,280 --> 00:00:45,740
 So if you're ever are reading multicast
 configuration guys or documents

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00:00:45,740 --> 00:00:49,780
 and they talk about the MCast source
 or just the source, that's what it

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 is. It's the server, it's typically a
 server that's generating the multicast

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00:00:54,180 --> 00:00:59,820
 traffic. And then your laptop or your
 PC or your tablet that's receiving

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00:00:59,820 --> 00:01:04,300
 that traffic, you are a receiver,
 a multicast receiver.

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 GDA, that stands for group
 destination address, right?

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00:01:11,400 --> 00:01:14,940
 Because at layer two and at layer three,
 the address is not going to a

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 broadcast, it's not going to a particular
 unicast, it's going to a group.

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00:01:19,180 --> 00:01:23,160
 So GDA is group destination
 address.

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00:01:23,160 --> 00:01:27,620
 We've also talked about the multicast
 distribution tree, which means,

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00:01:27,620 --> 00:01:34,660
 okay, if there's one or more routers in
 between the source and the receivers,

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00:01:34,660 --> 00:01:36,920
 there has to be some path built.

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00:01:36,920 --> 00:01:39,940
 So the routers know that when the multicast
 comes in to forward it down

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00:01:39,940 --> 00:01:43,080
 various interfaces until
 it reaches the receiver.

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00:01:43,080 --> 00:01:47,800
 So that path from the source to the receivers
 is called building the multicast

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00:01:47,800 --> 00:01:49,160
 distribution tree.

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00:01:49,160 --> 00:01:52,400
 And we talked a little bit about how
 that can be built either via a push

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 model, which means flooded
 everywhere or a pull model.

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00:01:55,680 --> 00:01:57,480
 We talked about that.

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00:01:57,480 --> 00:01:59,460
 And then I already defined PIM.

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00:01:59,460 --> 00:02:03,400
 PIM is a multicast routing protocol and
 it stands for protocol independent

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00:02:03,400 --> 00:02:08,520
 multicast. Not going to go into why
 is it called protocol independent.

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00:02:08,520 --> 00:02:12,440
 That would be more of a layer three discussion,
 but PIM is the most popular

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00:02:12,440 --> 00:02:15,460
 of the multicast routing
 protocols.

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00:02:15,460 --> 00:02:20,960
 So that concludes this particular discussion
 of an introduction to multicast.

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00:02:20,960 --> 00:02:24,260
 In the next video, we're going to start
 going into IgMP and look at the

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 details of that.