1. Programming Assignment #2
Implement a TCP analog for transferring
Due Date: Monday October 29 at 11:55pm
Hello everyone. Now I’m gonna introduce something about socket programming. First we will try to get a general idea about what socket is. Then we will introduce socket programming with Java and socket programming with Python. The corresponding reading material is the Section 2.7 in Chapter 2, and the project 1 description.
Readings: Chapter 3
Project II Description
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2. CSci4211: Programming Assignment #2
What should we do?
Implement a typical Client/Server model.
Client sends a file to server, through a unreliable network layer.
The source code of network layer has been provided.
Server gets message from network layer.
If the message is correct, write to a file.
Stop & Wait is enough.
GBN or SR is better!
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3. CSci4211: Programming Assignment #2
Why is it difficult?
Unreliable network layer
May drop your packet
May change content of your packet
May delay the packet
Even your ACK can be lost on the way!
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4. CSci4211: Programming Assignment #2
Several Cases
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5. CSci4211: Programming Assignment #2
Several Cases
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6. CSci4211: Programming Assignment #2
How to handle it?
Sequence number for dropped packets
Timeout mechanism for lost packets
Checksum for corrupted packets
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7. Things you may need to work on…
Socket Programming
File Operation
Timeout operation
Examples have been provided.
Checksum lib
hashlib in Python
MessageDigest in Java
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8. Things you may need to notice…
Start early!
Things are worse this time.
No code skeleton.
Let me know if you have any questions anytime.
Make your code east to read.
More explanations may follow.
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9. CSci4211: Programming Assignment #2
Q&A
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