HARD WIRED SERVER DESIGN SOFTWARE
HARD WIRED SERVER DESIGN CODE

If data (or for write, space) is already available in the buffer, the call might return very quickly.īut if the read or write can’t succeed, the call blocks.

HARD WIRED SERVER DESIGN CODE

When the destination socket’s buffer is full, calling write blocks until space is available.īlocking is very convenient from a programmer’s point of view, because the programmer can write code as if the read (or write) call will always work, no matter what the timing of data arrival.

When an incoming socket’s buffer is empty, calling read blocks until data are available.

Socket input/output streams exhibit blocking behavior: When a client connects to a server, that outgoing connection also uses a port number on the client’s network interface, usually chosen at random from the available non-well-known ports. When the port is not a standard port, it is specified as part of the address.įor example, the URL refers to port 9000 on the machine at 128.2.39.10. When you connect to the URL in your web browser, it connects to 18.9.22.69 on port 80.

Port 80 is the standard web server port.

Port 25 is the standard email server port.

HARD WIRED SERVER DESIGN SOFTWARE

When you connect to using SSH, the software automatically uses port 22. There are some well-known ports which are reserved for system-level processes and provide standard ports for certain services. Network interfaces have multiple ports identified by a 16-bit number from 0 (which is reserved, so we effectively start at 1) to 65535.Ī server process binds to a particular port - it is now listening on that port.Ĭlients have to know which port number the server is listening on. A single machine might have multiple server applications that clients wish to connect to, so we need a way to direct traffic on the same network interface to different processes.

Hard wired server design