Question

What is the difference between an ordinary socket and a TCP socket?. Also in a web server like IIS, how many TCP sockets can be created in a server?. I had read somewhere that when the client connects to a web server(on port 80), the web server creates a temporary port and replies to the client on the temporary port. Is that true ?.

Answer 1

As Andrew mentioned, socket is just an interface. Think about plug and socket; where socket is an external interface for the plug.

Now imagine a socket inside the computer and a plug coming from the outside world, plugged into that socket – that is, connected; now they would need to tell each other how they would communicate(that is, the protocol). The standard forms of protocol are TCP or UDP. See introduction to TCPIP.

A socket is defined by a protocol and
an address on the host. The format of
the address is specific to each
protocol. In TCP/IP, the address is
the combination of the IP address and
port. Two sockets, one for each end of
the connection, form a bidirectional
communications path.

An OS can have up to 65536 ports; in windows up to 1024 are reserved by OS for itself.

Yes, it is correct that a server(including IIS) takes on the initial request and forwards the connection to a redirected port. Worth a a glimpse link. Also, see performance tuning section if you want to limit connections to IIS.