1. TCP Socket Programming
Presenter :Nicole

2. Outline What is a Socket? Stream Sockets Server code Client code
Solution
Demo
Reference

3. What is a Socket? Socket Types
Sockets allow communication between two different processes on the same or different machines. To be more precise, it's a way to talk to other computers using standard Unix file descriptors. 
Socket Types
Stream Sockets
Datagram Sockets
Raw Sockets
Sequenced Packet Sockets

4. Stream Sockets Server Client Socket() Bind() Listen() request Accept()
Bind()
Listen()
Connect()
Accept()
Recv()
Send()
Close()
Server
Client
request
response
Data transmission
Data transmission

5. Server python code import socket
sk = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
host = “your IP address"
port = your port
sk.bind((host,port))
sk.listen(5)
print("Server start....")
while True:
connection,addr = sk.accept()
print("Got connection from",addr)
msg = connection.recv(2048)
print(msg.decode(encoding = "utf-8"))
connection.send("ok!".encode(encoding = 'utf-8'))
connection.close()

6. Client python code import socket
sk = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
host = “your IP address"
port = your port
print("connecting to server....")
sk.connect((host, port))
str = input("What do you want to do?")
sk.send(str.encode(encoding = 'utf-8'))
buffer = sk.recv(2048)
print(buffer.decode(encoding = 'utf-8'))
sk.close

7. Solution OSError: [Errno 113] No route to host-------因為server端防火牆擋住
(solution1) Service iptables stop
(solution2) Iptables -A INPUT -p tcp -m state --state NEW -m tcp --dport port -j ACCEPT
OSError: [Errno 98] Address already in use
# ps –x
# kill pID

8. Demo
server
client

9. Reference
What is socket