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244/Data Communications/Learning Resources

Interesting and helpful learning resources (short videos, demonstrations, animations, magic tricks and etc. )

confusion of LZW decompression algorithm, line10 "else {//code does not exists in dictionary": "an abnormal case shows up whenever the sequence character/string/character/string/character (with the same character for each character and string for each string) is encountered in the input and character/string is already stored in the string table. When the decompressor reads the code for character/string/character in the input, it cannot resolve it because it has not yet stored this code in its table. This special case can be dealt with because the decompressor knows that the extension character is the previously-encountered character."

Lecture 5

Magic Tricak to explain Parity check

Parity Simulation

Parity Error Detection Simulation

Decimal Remainder Caculator

CRC generator and checker demo

Cyclic Redundancy Check Simulation

Cyclic Redundancy Check Error Detection Simulation

CRC hardware Implementation

Lecture 6

Magic Trick to exaplian Hamming code

4 bits illustration for Hamming code

Hamming code Demo

Hamming code Simulation

Hamming Code 3D explanation

Lecture 7

Overview of encryption and decryption animation

what is cryptography

intro of cryptography

Caesar Cipher

vigenere Cipher

AES demo

Lecture 8

RSA Encryption

What the inventors say about RSA Encryption

Prime number

a simple example used for RSA and how difficult to break it

PGP demo

Lecture 9

Networks Topologies

OSI Model - How an email passes through each layer

OSI Demo

The OSI Model Animation

Lecture 10

ALOHA Protocolo

Slotted ALOHA Protocolo

Carrier Sense Multiple Access (CSMA)

CSMA demo

CSMA demo2

CSMA demo3

Retransmission Back-Off

Token Ring Demo

Lecture 11

Theses demos are used for illustration (have slight differnces with the descriptions in lecture notes). Please follow the descitpions in lecture notes/textbook and tutorials.