Lecture 1 - IP Multicast Basics and Addressing

Рет қаралды 154,599

8 жыл бұрын

This is the first video of a complete lecture series on IP Multicast and its implementation on both IOS and Junos routers with a focus on CCIE and JNCIE candidate requirements.
In this video we discuss the following topics:
- What is IP multicast and its relevance to CCIE and JNCIE
- How does IP multicast differ from broadcast and replicated unicast
- Why is multicast more efficient than broadcast and replicated unicast
- The addressing of an IP multicast packet, the class of IP space used, the packet structure and the flat nature of the Class D space
- The need to generate unique ethernet MAC addresses to use as destination multicast MACs
- The addressing of a layer 2 ethernet packet encapsulating IP Multicast
- How multicast IPs are mapped to multicast ethernet MAC addresses and how up to 32 IP multicast IPs can potentially map to a single MAC address

Пікірлер: 87

@illmatic87 7 жыл бұрын

Finally a well made, accuate video on IP Multicasting. Thanks!

@HarryLevinson 5 жыл бұрын

IMHO, this is the best KZfaq Networking series I have ever seen. Thank you!

@DecodingPackets 5 жыл бұрын

Thank you for your very kind words. They make us strive to do even better.

@soumyasiddharthdas1282 6 жыл бұрын

Perhaps the best multicast series on the planet. Really more than helpful. Thanks a lot !!!

@DecodingPackets 6 жыл бұрын

Soumya Siddharth Das Thanks! That made my day.

@rifleman542 7 жыл бұрын

These are excellent videos, I have never seen someone go so deep into explaining the 'why' of networking, its definitely a breath of fresh air, can't wait to watch your videos on other networking concepts. Hope you have plans for new topics. Thanks for hitting rock bottom and leaving no stone unturned to explain the details.

@PhantomVideoLive 11 ай бұрын

I'm trying to deep dive on IP Video 2110 and this is the first video series (from the networkside) that I have found truly helpful, thank you very much for your time and effort !

@mmm763 Жыл бұрын

I watched your multicast lecture series from 6 to 10......I would say this is best video series i have ever watched.

@patrickdee7365 4 жыл бұрын

Man you really know how to explain. Thank you

@stefanalexandru93 7 жыл бұрын

Best lectures about multicast I could find. This course addresses some key aspects that others don't. Keep up the good work.

@DecodingPackets 7 жыл бұрын

Thank you Stefan. We are making every effort to complete this series quickly (without compromising quality) so look out for new videos as they are added. Thanks again for your support.

@LuisAntonioGilRueda 6 жыл бұрын

Loved the level of detail and the background story of saving 15500 USD! Nice touch, great content!

@DecodingPackets 6 жыл бұрын

I am glad you are enjoying the videos. As for the side story, I guess it was not a big deal in the long run because if you look at IPv6 multicast, mapping the whole address into the MAC was not even a possibility. So essentially, they were able to take their experience from IPv4 mapping directly to IPv6 mapping (although mapping 32 bits instead of 23 which is at least more sensible).

@codysharlowa6397 6 жыл бұрын

Luis Gil ejajdkejeje

@codysharlowa6397 6 жыл бұрын

Luis Gil ⌛️⌛️⌛️⌛️🔚😄🎟🤣🙃🔚😀😋😃😃😄🤣😂😅

@Vorstellungskraft1 6 жыл бұрын

Your videos are brilliant! Thank you for taking the time to create them!!! Both the content is very much on the spot and your voice is incredibly clear and easy to understand. Will recommend to all my friends ^^

@DecodingPackets 6 жыл бұрын

Thank you for your kind words. I am glad you are finding the content useful.

@marshelsavarimuthu9726 2 жыл бұрын

Thanks. Simple but detailed explanation.

@6downtown9 5 жыл бұрын

I usually don't subscribe easily but after watching video you got my subscription.👍

@DecodingPackets 5 жыл бұрын

Well, I hope to not make you repent that decision.

@siddhunayak2615 5 жыл бұрын

Great job guys.... Thank you so much for these videos.. Really appreciate your hard work and passion towards IP networking.

@DecodingPackets 5 жыл бұрын

Thank you very much for your kind words.

@ShortGiant1 5 жыл бұрын

Great video! Like the reasoning presented at every step, makes it easier to understand the concept.

@DecodingPackets 5 жыл бұрын

Thank you for your kind words. Glad you are finding the content useful.

@dlghwns 6 жыл бұрын

Wow this was really informative and easy to understand. I'm a visual learner so I kind of drew what you were saying in my head as I watched along. I could only imagine if your lectures were animated....omygoodness

@DecodingPackets 6 жыл бұрын

Thank you for your kind words. With a limited production budged, unfortunately limited PP based animation is all that is on offer. You will probably see it being used more and more as the lectures get more complex.

@gdjm1991 6 жыл бұрын

Thank you so much for this video.

@adams2986 7 жыл бұрын

Great videos about multicast. But 224.0.0.9 is for RIPv2 not EIGRP :)

@DecodingPackets 7 жыл бұрын

Good catch Adam. Frankly I do not even remember if I had meant to say "224.0.0.10 is EIGRP" or "224.0.0.9 is RIP". Glad you are enjoying the video.

@tanishawalker5758 5 жыл бұрын

Great videos about multicast.

@DecodingPackets 5 жыл бұрын

Thank you for your kind words.

@shahabsandhu4034 5 жыл бұрын

Excellent presentation and explained really well!!

@DecodingPackets 5 жыл бұрын

Thank you for your kind words. I am glad you are finding the content useful.

@avi2123 6 жыл бұрын

Excellent ! Thanks @Decoding Packets

@DecodingPackets 6 жыл бұрын

You are welcome. We are glad you are finding the material useful.

@benlancini 4 жыл бұрын

Superb. Thank you.

@royalkamran Ай бұрын

Great explanation. what is the purpose of the MSB bit set to 0 in remaining 24 bits of multicast mac address ?

@LuisVegaTheNetworkVlog 4 жыл бұрын

Hey dude why didn't you continue with this ? your videos are very nice !

@uthayak 5 жыл бұрын

Great videos ,, nicely done , Thank you

@DecodingPackets 5 жыл бұрын

Thank you for your kind words.

@marianoaldogaston 5 жыл бұрын

great work, please go on

@DecodingPackets 5 жыл бұрын

Thank you!

@abdurrahmannoori5253 3 жыл бұрын

good explanation. thank you!

@torpersson8111 5 жыл бұрын

Please explain what takes place during a broadcast? If broadcasters switch to 5G rather that cable and satellite, which in the US could amount to 400 only. How does this affect the bandwidth utilization bearing in mind that there are many other prospective uses for 5G?

@vikrambhavsar3558 4 жыл бұрын

amazing tutorial. really helped :)

@dkoxperiakoziukov3808 2 жыл бұрын

Thanks for the good explanation. May I ask you a question? I have a streamer running on my router OS embedded. The stream is coming over the udp to the multicast address. When I route the stream to my internal router interface (where PC is connected) VLC is successfully connecting and playing video. But I need to stream outside and when I rout the stream to the external interface I see the multicast traffic running (with tcpdump), but my VLC on my local PC doesn't connect anymore. My provider told me they have IGMP and PIM set and running. Unfortunately I cant check the stream as I have no other available PC. And the VLC on the smartphone doesn't support udp routing. What I misunderstood? What am I doing wrong?

@amrkhater833 2 жыл бұрын

I had watched all the series and in fact it's brilliant. Can you please share the PowerPoint document ? Any way, thanks for your great efforts

@naveenkumarm7339 4 жыл бұрын

I am Big Fan of your Multicast series !! Thanks a Lot. Why don’t you make basic videos of SD WAN ?

@SkyDevil0007 5 жыл бұрын

make it correct sir 224.0.0.9 is for RIP and 224.0.0.10 for eigrp thanks and ur video is really helpful ..keep making

@DecodingPackets 5 жыл бұрын

Duly noted. I am glad you are enjoying the content.

@lxzhang4911 2 жыл бұрын

Thanks for the video. What is "AS" short for in the last line of the slide in 10:14?

@saurabhthote8667 2 жыл бұрын

at time 22:16 , you have minus 4 bits from 32 , Can you pls help in understanding "From where 4 bits comes from.". I am unable to understand. This Video is truly informative. 1110 is common in which IP range ?

@dua-dhikrseries4921 3 жыл бұрын

I still didnt understand why 25th bit is fixed to 0..can anyone explain?

@flashblog1679 Жыл бұрын

how do i configure multicast on ubuntu server 20.04?

@Djsore22 3 жыл бұрын

DO you have any idea that how I can develop a multicast or unicast app?

@johnclarkson6120 5 жыл бұрын

hi，great video，thx, but if any possible to record Inter-AS lab for multi vpn. One thing is that Cisco has a doc to explain multi vpn by using 27profiles,but without Inter-AS staff. So question is which profile support Inter-AS environments.

@dyadaval 4 жыл бұрын

Hi, content is very good. But can you share the link for the slides, these help for quick refresher.

@balajik25 3 жыл бұрын

Dear Sir, how to secure multicast ip's in network other then vlan & vpn

@Amit-wx9km 4 жыл бұрын

Gud

@robertmarotta3806 5 жыл бұрын

Hello I have been trying to get PotPlayer to open and play an rtsp-multicast stream via a cmd prompt, but have had no luck. I know how to do this with VLC where I can get it to open and display/playback the routed stream [using the command "vlc --rtsp-mcast rtsp://192.168.xx.xxxxx/ch0"] on my PC. When I check my Wireshark trace from the target PC I can see it is indeed a multicast stream received. When I open a command prompt in the PotPlayer directory and issue the command "PotPlayerMini64.exe --rtsp-mcast rtsp://192.168.xx.xxxxx/ch0", all it does is open the player, the stream never plays for me. When I issue the command "PotPlayerMini64.exe --rtsp rtsp://192.168.xx.xxxxx/ch0", it will open the player and start playing the source stream, however when I run Wireshark I can see in the trace the protocol is only TCP and not UDP. Can you provide the correct cmd line "instructions" for this to work? Thanks

@siddhunayak2615 5 жыл бұрын

Though the 5 unmapped bits , maps 32 IP's to the same multicast mac, I guess that shouldnt be problem w.r.t traffic..Because though packets do not get dropped at L2, if somebody spoofed and send multiast streams, they will get dropped at Layer 3 right... Correcct me if my unerstanding is wrong.

@DecodingPackets 5 жыл бұрын

You are correct. An explicit state must exist at L3 for the packet to reach the final hop. The only problem usually is if two or more of the overlapping multicast groups are active in a non IGMP snooping VLAN, and a device is only interested in one of those groups, it can inadvertently process both streams only to drop packets from the stream it is uninterested in.

@_moonxd667 5 жыл бұрын

Unicast can cause packet loss?

@DecodingPackets 5 жыл бұрын

I am not sure what you mean by that. Unreliable unicast (e.g. UDP) can cause packet loss but are you referring to something specific from the video?

@Miramintu 5 жыл бұрын

Nicely explained, thanks. BTW where can I get the slides?

@DecodingPackets 5 жыл бұрын

We are working towards posting the slides, unfortunately since 2017. Lots of backlog but will try to get this done sooner rather than later.

@nurojlama2536 3 жыл бұрын

hi could u provide these slides?

@aot9339 5 жыл бұрын

Between 9:13 and 9:18 when saying 224.0.0.255 (referring to /24) can you give other examples.

@DecodingPackets 5 жыл бұрын

It is not unlike Unicast in structure so any address (from class D if you only want Multicast addresses, 224-239) where the first three octets stay constant and the last octet spans 0-255. E.g 235.1.2.0 - 235.1.2.255. The main point of that particular excerpt is that we are representing a range of addresses rather than a subnet.

@aot9339 5 жыл бұрын

@@DecodingPackets Thanks. It's clear now. 👍

@DecodingPackets 5 жыл бұрын

Awesome

@VikasGupta-fn3db 5 жыл бұрын

Can you please do a video on BiDir Pim and SSM as well?

@DecodingPackets 5 жыл бұрын

We are planning to restart the IP Multicast series in the very near future. Those two topics are definitely on the list.

@GabrielTorres1974 3 жыл бұрын

7:00 = 2^28 = 268 million, not 228 million

@torpersson8111 5 жыл бұрын

How do I contact the author?

@DecodingPackets 5 жыл бұрын

These comments are read by the author. Do you want to reach out privately?

@torpersson8111 5 жыл бұрын

Yes, I would like his recommendation on a resource for setting up a Multicast operation. Also note that the delivery could be one way communication and wonder how the connection by multiple recipients to the router looks like.

@DecodingPackets 5 жыл бұрын

nb@decodingpackets.info