Internet Modules

Kamaelia has a wide selection of components to allow you to implement TCP and UDP based systems, including Multicast capabilities and simple chassis or making servers. These are mostly found in Kamaelia.Internet.

These components implement the low level functionality for making and maintaining connections - they do not implement any particular network protocols. Other components do that and can be used with these to construct more capable servers and clients.

Making a TCP socket connection to a server

• Kamaelia.Internet.TCPClient
  
• Kamaelia.Internet.TCPThreadedClient

The TCPClient component simply makes a connection to a server. Its inboxes and outboxes receive and send data from/to that server. This is very easy to use.

TCPThreadedClient is identical to use, but differs in implementation. It run its own thread and so doesn't need the Selector component)

Being a TCP socket server

• Kamaelia.Internet.SingleServer
• Kamaelia.Chassis.ConnectedServer
• Kamaelia.Internet.TCPServer

SingleServer is the simplest kind of server to use - it allows one client to connect at a time, and its inbox and outbox communicate with that client.

ConnectedServer is more powerful - it can handle lots of clients simultaneously. It is a kind of factor component: every time a client connects it spawns a component (known as the protocol handler) to deal with that connection.

ConnectedServer is built ontop of TCPServer which provides the underlying handling of the socket connections. By spawning ConnectedSocketAdapter components to manage the socket for each connection.

Sending and receiving UDP datagrams
The Kamaelia.Internet.UDP module contains components for sending and receiving datarams.


Multicast

• Kamaelia.Internet.Multicast_receiver
• Kamaelia.Internet.Multicast_sender
• Kamaelia.Internet.Multicast_transceiver

These components provide a simple way to send and receive (or both send and receive) multicast datagrams.

Network simulation

The Kamaelia.Internet.Simulate module contains components that simulate the kinds of problems you might get on a network - out of order packet delivery, lost packets etc.

Supporting components

• Kamaelia.Internet.ConnectedSocketAdapter
• Kamaelia.Chassis.Selector

ConnectedSocketAdapter (CSA) components are spawned by the TCP client and server components to look after actual communication with the TCP socket.

Kamaelia.Chassis.Selector is designed for dealing with checking to see if any network connections are active, and notifying CSAs that they can send/receive data. This allows individual CSAs to pause when idle - without having to block up the system or waste processor cycles by constantly polling.

If you are just using the facilities provided for implementing clients and server you don't need to worry about these components!


-- Matt Hammond, April 2007