many many many many server types all there

all servers

1. 1

2. Server Design
Iterative, Connectionless
Iterative, Connection-Oriented
Concurrent, Connectionless
Concurrent, Connection-Oriented
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3. Connectionless vs. connection-oriented
UDP vs. TCP
Reliability issue? TCP wins.
Support of broadcast or multicast? UDP wins.
Real time applications? UDP may win.
Client and server must use the same protocol
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4. Iterative vs. concurrent
Iterative server handles one request at a time.
If another request arrives while the server is busy
handling an existing request, the new request has to
wait.
Iterative servers are easier to design, implement, and maintain.
Iterative server is not good for a service with a long “request
processing time”.
Concurrent server handles multiple requests
concurrently.
It can decrease the response time.
It can achieve high performance on a server with multiple
processors.
It can achieve high performance by overlapping processing
and I/O.
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5. 5
server
client being
served waiting clients

6. 6

7. 1.Create a datagram (UDP) socket and bind to the well-known
address for the service being offered.
2.Repeatedly receive the next request from a client, formulate
a response, and send a reply back to the client according to
the application protocol.
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It is the most common form of connectionless server, used
especially for services that require a trivial amount of
processing for each request.

8. 1.Create a stream (TCP) socket and bind to the well-known address for the
service being offered.
2.Place the socket in passive mode, making it ready for use by a server.
3.Accept the next connection request from the socket, and obtain a new
socket for the connection.
4.Repeatedly receive a request from the client, formulate a response, and
send a reply back to the client according to the application protocol.
5.When finished with a particular client, close the connection and return to
step 3 to accept a new connection.
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A less common server type used for services that require a trivial amount of
processing for each request, but for which reliable transport is necessary.

9. Master 1. Create a socket and bind to the well-known address for
the service being offered. Leave the socket unconnected.
Master 2. Repeatedly call recvfrom to receive the next request
from a client, and create a new slave thread to handle the response.
Slave 1.Receive a specific request upon creation as well as access to the
socket.
Slave 2.Form a reply according to the application protocol and send it
back to the client using sendto.
Slave 3.Exit (i.e., a slave thread terminates after handling one request).
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It is an uncommon type in which the server creates a new thread
to handle each request.

10. Master 1. Create a socket and bind to the well-known address for
the service being offered. Leave the socket unconnected.
Master 2. Place the socket in passive mode, making it ready for
use by a server.
Master 3. Repeatedly call accept to receive the next request from
a client, and create a new slave thread to handle the response.
Slave 1.Receive a connection request (i.e., socket for the connection)
upon creation.
Slave 2.Interact with the client using the connection: receive request(s)
and send back response(s).
Slave 3.Close the connection and exit. The slave thread exists after
handling all requests from one client.
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11. ANY QUERRIES???
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