OSPF Multi Area Explained

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In this video we're going to be looking at multi area OSPF.
Single area OSPF (Open Shortest Path First) works great in small networks however as the networks grow, some down sides to single area OSPF start to surface.
Huge LSDB!
OSPF will gather the entire network information and create an LSDB. This database will be the same on every router on the entire network. This can become very large filled with information that the router doesn't even really need.
Massive routing tables!
Along with the large LSDB, huge routing tables will be generated on each router. This will contain every subnet within the entire network!
Updates everywhere!
OSPF is great at responding to changes, however in such a large network problem can occur. Every router will need to reevaluate all routes and run the SPF algorithm anytime a change occurs, even if that change is as small as a network cable being unplugged. I’m sure you can imagine the work load required in a large network.
The solution!
OSPF multi areas is designed to segments your network and allows routers to summarise routes between the areas reducing the problems mentioned above.
Designing OSPF multi areas takes some planning to get the full benefit.
Each area should contain subnets that can be summarised.
All areas must connect to the backbone area/Area 0
#ccna #cisco #networking

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What is great about your videos is that you explain the technology without jumping into configuration, this way we can understand what is going behind the seans< also your way of explanation is wonderfull, you are a great teacher.

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Thanks eedept! Glad you liked the video!!!

[@ardentdfender4116]

I'm currently learning this topic for taking my CCNA soon and man your breakdown is so damn helpful its unreal. I took me hours to just try and understand OSPF. But you video presentation does this so well i understood it. You do a damn great job man. COme back soon with new stuff.

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Improved a lot than the very start, and that super boom intro music 🔥

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[@hardwiired]

Thanks for the video!! My college professor has just decided to make his own CCNA assignments with very vague instructions. This has helped!!

[@aruizsilva]

Much easier than the previous one on single area OSPF I must say. Thanks for the effort!

[@Certbros]

You're right. Once you get single area, multiple area becomes much more simple. 👌

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so glad to see you guys back!

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I am a computer Science and Engineering student, I stumbled across your video today, and this is hands down the best explanation I've ever seen!!! Thank YOU! This was AWESOME!!

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Wow, thanks! Great to hear you liked the video! Good luck with your studies.

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For visual learners this is incredible, thank you kindly and please have more videos for CCNA and NP, Thanks Bros

[@amrkamran4884]

Proper good Information. Really well summarized.

[@Certbros]

Thanks Amr! Great to hear.

[@purplecrayon7281]

Best explanation of multi-area ospf! thanks!

[@EyeIn_The_Sky]

Great explanation. I wish you had one about the different Area types, that is the hardest OSPF aspect, for me at least, to understand and grasp and even to begin using it in the real world on which type you would use when and why in a practical sense.

[@saimkhan89]

The animations are great. We need more videos like this. Would be great if more detail and information is included (LSA types etc.)

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Thanks Saim!

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Again, well explained. I loved it.

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This is still gold, me trying to brush my networking concepts after 3 years now !!

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Best explanation I found on youtube about the subject.

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Extremely precise explanation! I thank you for this content!

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You're welcome Alexandre! Glad to gear it helped.

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Very good way to get the concepts down. Haven't seen better videos on youtube about or for Cisco/CCNA/Networking

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Thanks Christian!!

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Great content! Very clear and concise, good job guys.

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Hey @centbros i just love how you explain any topic. Keep the fire burning man!!!

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Thanks Danveer! More videos to come

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Excellent Explanation, thanxx again!!!

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Enjoyed this series 😌

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Well, that was helpful. Love your videos! Thank you!

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Thanks! Glad you liked it!

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Amazing video man. Please keep them coming.

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Thanks Harsh! Appreciate the comments!

[@TheFriedLife]

superrrrbbbbbb superbbbbb..mind blowing sir...we want more such videos on OSPF LSA types, OSPF areas..thanks a ton...

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Thanks Arijit!

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just perfect - thank you

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Awesome video as always 👍

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Certbros.. Thank you for making life simple for us. Ought to say, it feels as if too good(easy) to be true..

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Thanks for the comments Shakil! Keep it simple, the detail can come later.

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the guy or guys behind this channel are great no doubt

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Great explanation. Thanks.

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Your videos make "network nerding" very easy for me! An EIGRP video would be nice as well.

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Thanks Bryson! EIGRP next

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These explanations make it so simple

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Thank you very much for clear , concise and wonderful presentation

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You're welcome! Thanks for the comment!

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Another really useful video - Thanks.

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Thanks for the video!!

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liked commented and subscribed, keep those great vids coming!

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Awesome thanks!

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Great video. Very well presented, easy to understand explanation. Subscribed based off of this video alone.

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[@rajsonu27]

Nice one, easy and simple , thanks mate

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Thanks

[@guohenry209]

So the main problems of using single OSPF in multiple areas: 1. A lot of information of LS(including useless information) will occupy the disk space of router 2. Hard to search a piece of specific information in such huge LSDA 3. Updates are flooded throughout all the network occupying a lot of resources 4. Summarizing all the reasons above, using single OSPF in multiple areas will occupy a lot of resources (including disk space, bandwidth, power, etc.) Backbone area: every other area must join to the backbone area. ABR: Area border router, whose interfaces in two or more areas and can summarize some specific area LSDB(e.g. 10.0.0.1+10.0.0.2-->10.0.0.0/30). ASBR: Autonomous system boundary router, connecting to other non-OSPF routing protocols such as BGP

[@ElreyRayo]

is there a multiple OSPF instance solution then?

[@arghosinha1424]

Amazing work, very helpful, thanks a lot.

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Thank you. You're welcome!

[@kaidjohardudhiawala2549]

Fantastic explanation

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Thank you for this tutorial

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Thank you for the great videos

[@khansamrah90]

this video really helps a lot. Thank you

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Thanks!

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Thank you, your videos are really helpful! :)

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Thanks!!!

[@weactweimpactcharityassoci3964]

Great explanation i just became a new subscriber in your channel

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Way of teaching is excellent.. Well done and Keep it up

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Thanks Umair!

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Great stuff 👍

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Thank you!

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Very nicely explained

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Amazing :D Subscribed!

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Thanks!

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Wow... you are just amazing.

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Thanks

[@seantellsit1431]

Great video. I think there are some things that should be revisited. A) there always needs to be an Area 0. B) Other areas MUST have at least 1 router in Area 0. C) Areas dont nessicarily follow phyiscal or logical connections, but they can and sometimes they should.

[@ibrahemkurd8792]

thanks man that was helpful

[@Certbros]

No problem at all. Glad you liked it!

[@user-ul1hb3eb1g]

Very well explained thaks

[@user-rb8hg8ge5b]

Interesting and Informative

[@SSAKannadiga]

The videos on OSPF are nice and crisp. You should think of adding the different types of LAS video to the list

[@arghosinha1424]

Very informative 🖤

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Thank you!

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Great video, thank you!

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Thanks Troy!

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Man you saved my life

[@pascualsevilla5590]

Additional Notes aside from the description given above. Backbone Routers - This are routers that are in or partially in the backbone area. ABR ( Area Border Routers ) - Routers that connect to more than 1 area. Internal Routers - This are routers that are in a single area but not the backbone area. ASBR ( Autonomous System Boundary Router ) - This are routers that are connect to other non-OSPF routing protocols (i.e EIGRP or BGP)

[@pdedoaa9350]

really it simplify the protocol and explain it in proper way

[@Certbros]

Thanks! 👍Glad you liked it.

[@rizz_mistress]

It is well broken down and easy to understand

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Thanks Franklin!

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Like first, then watch!

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Thanks so much! Could you please make a video on BGP?

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Great video

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Great video, thanks !

[@Certbros]

Thanks!

[@jeffabrew5262]

Greetings Cert Pros, Excellent Training on OSPF! I will be continuing on with more on OSPF, Subnetting, VLANS and CLI. Are the audio transcripts available for download for each training module? It helps a lot with note taking. I fancy a few cups of tea and biscuits while watching the training. :0) Cheers! Thank you -Jeff Abrew

[@PETAJOULE543]

Great video, now I feel that I completely understand OSPF. Could you make video explaining BGP as well?

[@Certbros]

Thanks! I will definitely be making this at some point

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Awesome❤

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Thank you Saloni!

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Excellent

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master piece

[@Certbros]

Thanks!

[@YousufBabarzai]

Great videos, watched of em. Would you plz do a similar graphical video on other routing protocols such as RIP, RIPv2, EiGRP and explain the administrative distance, administrative vector and link state. Thank you

[@Certbros]

Thanks!! This videos are planned. Working on EIGRP next.

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thankyou

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Thank you

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ty

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Thanks !!

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very good

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dude you are the best you British genius

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Haha 🤣 Thanks Gavin!

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Great videos

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Thanks!

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Really nice video.!!

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Thanks Diego!

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Awesome stuff!!! Do you have one about HSRP planned? :D (as a Cisco tech engineer myself, these videos are AWESOME :D )

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Thanks! Yes it's 100% on my to-do list!

[@MarsieHellscream]

@@Certbros Awesome! :D These videos are quite useful when you study since they cover the basics (I recently got my CCNA R&S )

[@waleed3able]

could you please do videos on LSAs and also on Stub area and NSSA for OSPF ?? Will be waiting for you explaining these topics

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verry helpful content

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Thanks

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great info

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Thank you!

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thanks!

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You're welcome Randy!

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Thanks man

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Thanks Robert!

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Great! :)

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thanks

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THANKS

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great video

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Thanks!

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great

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I like how the Routers get excited whenever they receive LSUs😄😄

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🤣

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good content.

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thank you dear

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Thanks

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Addictive videos

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Thanks!

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@@mohamedattouchi4834 Thank you Mohamed! Really appreciate the comment. I'll add your suggestion to my list of future videos. Thanks again 🙏