Checksum

Рет қаралды 301,637

11 жыл бұрын

Checksum is a method of checking for errors in a communications system.
I'm Mr. Woo and my channel is all about learning - I love doing it, and I love helping others to do it too. I guess that's why I became a teacher! I hope you get something out of these videos - I upload almost every weekday, so subscribe to find out when there's something new!
For categorised playlists: www.misterwootube.com
Main channel: / misterwootube
Discussion: / misterwootube
Worksheets and other resources: woo.jamesruse.nsw.edu.au

Пікірлер: 207

@Truckito2007 10 жыл бұрын

Man, your presentation/teaching skills are spotless. I'll be watching your videos before my next presentation. Thanks

@alphamale4292 9 жыл бұрын

Sir, you are the kind of teacher that doesn't induce the students to sleep. And there's only a few instructors that have this talent.

@sinalorululu4627 9 жыл бұрын

couldn't be more clearer.......that was very helpful.....hands down you are a good teacher

@coo-kies 7 жыл бұрын

Most fabulous and enthusiastic CS lecturer ever. Love it!

@themightyant. 3 жыл бұрын

Knowledgeable, clear, enthusiastic and dynamic. Great teacher.

@bathwars 7 жыл бұрын

WOW. Thank you Eddie. Literally three months of confusion cleared up in 6 minutes.... Thanks again

@theindiangirl9435 3 жыл бұрын

watching after 8 years of uploading, and I am finally satisfied here. -29 April 2021

@granceroblast 9 жыл бұрын

Great charisma. I think you will do well as a professor or a owner of a gigantic cram school chain. I hope you will post more educational videos like this and your KZfaq channel will flourish.

@furythree 8 жыл бұрын

this is the top google video search result now for checksum! nice work. I was surprised to see a Ruse logo to the side. Recogised the AHS and gesta non verba lol! which year did you join/start teaching? which subject do you teach? i dont remember learning checksum even in SDD

@unknwn_usr3077 7 жыл бұрын

haha.. Im also asking the same question to myself about the subject he teaches. I think he is a mathematician. Most of his videos are math. But I would like to see more computer videos like this.. I know there are lots of video tutorials on youtube but I really find his teaching interesting and it really sticks with my brain xD

@TheGamerGameplay1 5 жыл бұрын

Hahah, funny. Today this guy is rocking

@MrSp3ctre 3 жыл бұрын

You're damn right about that :)

@raheemkhan2007 Жыл бұрын

Quite a famous person now :).

@unknwn_usr3077 7 жыл бұрын

Mr. Woo, Please upload more videos like this. Really simple and easy to understand your teaching. I like it

@RaRapidum 5 жыл бұрын

Great video, but I really really hope that that "keyboard master race" dude in the background STOPS !

@nabeelahsan504 4 жыл бұрын

@ahmetkarakartal9563 3 жыл бұрын

hahahaha

@ShahrinRahman Жыл бұрын

😅😂

@GTexxClub 6 ай бұрын

Lmao 😂

@scottkennedy3071 7 жыл бұрын

Great video, clear and easy to follow. First time I've walked away feeling good after trying to get my head around this principle.

@alrineusaldore6764 4 жыл бұрын

I just subbed because of an interesting random math video, but I would have never thought that you would actually help me with stuff I needed. Thanks for the awesome video! I never understood checksum before it.

@demetdemirkiran36 7 жыл бұрын

Cramming for my last final at uni, thanks for helping me with Computer Networking Mr.Woo :)

@ArsenalNut17 8 жыл бұрын

Great videos, taught so clearly and with great atmosphere.

@billyfairbank 8 жыл бұрын

Great video and glad I found your channel. Obvious passion with great teaching talent.

@robertjennings5558 10 жыл бұрын

Very well said Mr. Woo. I love your presentation style.

@jasonhuang222 6 жыл бұрын

Great explanation ! You really make things easy to understand. Thank you

@TheMaxxy911 11 жыл бұрын

Fantastic explanation! I feel I'm finally starting to get a handle on the concept.

@JohnSmithhh 2 жыл бұрын

Man you're explanation is sooo clean ! Thanks

@nadas.2079 9 жыл бұрын

This is amazing, I've learned so much in under 10 minuets what my professor was trying (and failing) to teach in an hour!! thanks a lot

@ibradul 3 жыл бұрын

No clue what this is about, clicked randomly but kept watching because I was so drawn by how good your presentation skills are

@DuckieMcduck 5 жыл бұрын

This is one implementation of Checksum however it is abstracted a bit much to make it easier on the students, hindering its purpose. It's usually done with the sum between all words in the msg like in the video, but the final value is given its one's complement and appended to the message. If the transmission is correct, repeating the procedure on the other end (except now with the appended checksum) will result in FFFF assuming 16 bit words. No division operation needs to takes place.

@dylanmm007 11 жыл бұрын

Thank you so much Eddie, this and the parity check video was so helpful.

@ajaygulani3086 3 жыл бұрын

I can see why Eddie Woo is one the best teachers in Australia!

@he3461 9 жыл бұрын

Loved the way you teach :) Thank you for such a spirit :D

@L33t3n 9 жыл бұрын

I absolutely agree ^^ pretty cool :)

@fuego1529 7 жыл бұрын

Thanks for uploading this video, really helped me out. You make an awesome teacher btw =)

@basavarajmsasalatti362 2 жыл бұрын

Hi Eddie, very much impressed the way you explained checksum . On databases also there is checksum not able to understand by reading . If you have anything on that can you please upload . Thanks

@NK-iw6rq Жыл бұрын

This gentleman is a wonderful teacher

@marianoen3158 5 жыл бұрын

wow , this is a real top of the class teacher , never saw one of those in my life really interesting

@shabeenabanu1373 9 жыл бұрын

Can you plz give example of hexadecimal checksum?Does division hold good for hexadecimal too?

@pandurangathota1721 7 жыл бұрын

very good presentation of the concept. Really i liked it.

@kristianwalsh9834 7 жыл бұрын

Wow, this is awesome. You explained that really well. Was mesmerised by the whiteboard! Wish my Uni had them

@sodiboo 2 жыл бұрын

I remembered my classroom in like first grade had one of those. I've never really looked into it too much and as far as i can remember, this is the first time i've ever seen one since then. I didn't go to second grade at the same school since i moved.

@pianoman42421 10 жыл бұрын

You sir are an excellent teacher. Thank you very much.

@theone3746 6 жыл бұрын

I love your energy.

@michaeldespotopoulos9424 9 жыл бұрын

Thanks for the video. Is that Fletcher's checksum?

@asiandurian11 5 жыл бұрын

So is there any way to get around the balanced offsets on your data (when you changed 23 to 24 and 11 to 12, resulting in the same checksum?) Seems like the size of the divisor wouldn't even matter here. Perhaps it is so unlikely that it's not a significant problem? Or is there a secondary check that is not a checksum that can detect this? If anyone knows, I'd appreciate the knowledge.

@Adam_Bell32 9 жыл бұрын

love your videos so helpful but how is the divisor chosen

@hankmoody666 5 жыл бұрын

Best teacher ever.

@krishnangopal8614 9 жыл бұрын

Hi Eddie.. Its really a nice video. But I have question for you. You have a data 25 11 12 13 .. initially which gives you checksum value 8. and when you changed the data to 24 12 12 13.. also gives you the same value 8. This lies under the error but still it passes the checksum value. In such case how can we ensure the data integrity?

@sunny99179 8 жыл бұрын

Thank you it help a lot to understande how checksum works...i appreciate so much.

@henryabirafeh2835 10 жыл бұрын

You have a great enthusiastic characteristic personality and you have a cool accent :p. Your video rocks.

@maniijuan 4 жыл бұрын

where have your videos been my whole life (aka these past 8 weeks in my networking class lol)

@blessed5586 9 жыл бұрын

Is this operation the same thing as a modular checksum? Thanks.

@vigorzang3463 8 жыл бұрын

Um, very helpful man, keep doing this!!

@nicolechung6805 8 жыл бұрын

you are awesomeee! such clear explanation that I wish you're my lecturer xD

@ekhliousful 2 жыл бұрын

where to watch the full Video/lecture/lesson?? the links in the description are infected and not working?

@Pseudonym25 11 жыл бұрын

This was very helpful. Thank you so much!

@tyty685 7 жыл бұрын

Nice video, thanks for the help. The remainder for the second example is 9 (opposed to 7).

@luckysharma6346 5 жыл бұрын

what if sum of bits and checksum changes in accordance, for eg if sum changes to 88 and checksum also changes to 9, then would that message will be flagged as incorrect ?

@pradeepbabu7645 10 жыл бұрын

great explanation , and i am vary glad to have a Eddie Woo in this profession u deserve that position,and i think i have to copy some teaching techniques from you .. any way thanks a lot..

@sujeetrai1553 Жыл бұрын

😂

@RohanShah05 11 жыл бұрын

Great work man... Thanks a ton... This surely helped...

@ABDULLAHAIi 9 жыл бұрын

I like the way you explain .. I got it right a way .. BIG like + subscribe .. I can't wait to watch the rest of your videos .. keep it up

@makharsa12 6 жыл бұрын

Thank you for such great channel

@ajayguhan 6 жыл бұрын

Wow, superb teaching..!

@ebtihalm9368 10 жыл бұрын

Thank you so much , It helps me a lot to understand checksum in NW , Keep going :)

@Geadalu 8 жыл бұрын

You're incredible, oh my gosh! :O You're really really good at teaching! *____*

@Chivalryck 7 жыл бұрын

Thanks you very much from Uruguay, you really help me a lot with this video.

@NaifAlqahtani 8 жыл бұрын

great vid! but how do both computers know what number is the divisor??????? like in parity the check digit is based on the numbers added together, but here it depends on the divisor which can be anything!!!!!!!!!!!!!

@ayeshasaif7179 8 жыл бұрын

What we have learned in Cambridge O levels is that we have to divide that sum "X" by 256 take the answer in whole number , Y. Then Z=Y*256. Then calculate the difference (X-Z). This value is checksum. example: X=11855 1. 1185/256 = 4.629 2. nearest whole number = 4 3. multiplying by 256 gives Z= Y*256=1024 4.The difference (X-Z) gives the check sum: (1185-1024)=161 5. this gives the check sum= 161 BTW I really love your lectures. :)

@gnasher5677 7 ай бұрын

I think you made a mistake in line 4

@TheGamerGameplay1 5 жыл бұрын

Thanks for the vid, Eddie! :)

@tobiasbeetz438 4 жыл бұрын

Great vid thanks! One question though: Where is advantage of using a devider instead of just comparing the sum?

@aronquemarr7434 4 жыл бұрын

If the sum exceeds 26, you cannot put it in the message.

@satellitesage2487 4 жыл бұрын

@@aronquemarr7434 I had the same question, so thank you!

@GualbertoHinojosa94 4 жыл бұрын

Very Good Night Engineer ... One question ... You can take Checksum to a KM of a Suzuki Vehicle

@ozguy5196 6 жыл бұрын

What is the student saying around 5:18?

@gavaho 6 жыл бұрын

awesome!! u made me understand the checksum, ty kind sir

@abdumannonmurodiy 3 жыл бұрын

Dude ur so good at teaching.

@trit2656 Жыл бұрын

Very clear explanation. Thanks.

@ecke1011 6 жыл бұрын

Love the use of the smartboard

@TonyStark-of7tq 6 жыл бұрын

Thanks!!! Helped me a lot!!

@therealdeal3042 7 жыл бұрын

eddie would really apreciate u coming over to greenford high school and teaching it wouldbe great

@Jimakos1998 6 жыл бұрын

great video

@roxas2442 8 жыл бұрын

Wohoooo your vids helped our class alot thanks heaps mista woooohooooo!

@dragonore2009 6 жыл бұрын

We use checksum in computer science all the time, it is an important piece in knowing if credit cards are valid for example.

@vaibhavbharate1607 3 жыл бұрын

sir why you not uploading full video's why ?

@chaitanyanarayan7004 8 жыл бұрын

HOLY JAMES RUSE. THE DREAM!!!!

@jwoodmotivation 7 жыл бұрын

This has helped me a lot but what would the question be if it came up in an exam?

@evandiskett2512 7 жыл бұрын

Josh Wood design a hamming code an complete a parity check. identify any flaws in check method exact words off my exam

@juliusballaran5150 11 ай бұрын

Man, I wish you were my teacher in college!

@driestroyer 5 жыл бұрын

Thank you very much Eddie!

@JjackFrost 6 жыл бұрын

Saved me. Thank you so much

@yuzhixiao8809 9 жыл бұрын

This is very nice! thank you!

@multiSPEEDitUP 5 жыл бұрын

dude, that was great.....ez.... no bs. clear. have an upvote.

@DJDiskmachine 9 жыл бұрын

Eddie WOOP! Brilliant! ^_^

@sss_shan721 3 жыл бұрын

Thank for your explanation!

@karlreimers 2 жыл бұрын

Very nicely explained-

@miraliska312 9 жыл бұрын

Perfect, thank you!

@HumbleHistorian 5 жыл бұрын

you teach awesome !

@cook7772 8 жыл бұрын

I'm confused. I learned checksum to add al the numbers then flip the bits (add one depending if I'm using ones or two complementary addition.) then you add that the end of the message. The reserver adds it up and should get 0 if right. This looks like a mix of checksum (the one I learned) and CRC. So I'm confused.

@tsp8855 8 жыл бұрын

+cook7772 I think the ones complement and two's complement thing is exclusively for dealing with negative numbers, while checksum's main goal is to provide data integrity.