Ports and sockets:

An important concept in the TCP and UDP protocols is that of a port. A port is a conduit into a host on the internet. In this context, a port is a logical idea - it is not the same as a parallel port or a USB port, which are actual pieces of hardware to which you can connect wires.

TCP communication into and out of a computer is via numbered ports. Ports numbered from 0 to 1023 are reserved for dedicated services. For example, port 80 is used for web server communication, port 21 is used for FTP requests and port 110 for POP3 email communication. This allows a client to request a particular kind of service and allows servers to listen for particular kinds of requests on specific port numbers..

Figure Using ports to distinguish the service required

If you are writing Java programs that use ports then you should avoid using ports in this dedicated range, unless you intend to use one of these services. UDP communication also uses numbered ports. The maximum port number for both TCP and UDP is 65534 (as this fits into the 16-bit slots reserved for port numbers in the packet header).

A socket is the software mechanism that allows programs to transfer data across the internet using TCP/IP. A socket object in Java is associated with a port number and the address of a host, specified either as an IP address or in symbolic form. For client-server communication, we need a matching pair of sockets, one on the client and the other on the server. We will show how we program this later in the unit.

Java Assignment Help - Java Homework Help

Struggling with java programming language? Are you not finding solution for your Ports and sockets homework and assignments? Live Ports and sockets experts are working for students by solving their doubts & questions during their course studies and training program. We at Expertsmind.com offer Ports and sockets homework help, java assignment help and Ports and sockets projects help anytime from anywhere for 24x7 hours. Computer science programming assignments help making life easy for students.

Why Expertsmind for assignment help

1. Higher degree holder and experienced experts network
2. Punctuality and responsibility of work
3. Quality solution with 100% plagiarism free answers
4. Time on Delivery
5. Privacy of information and details
6. Excellence in solving java programming language queries in excels and word format.
7. Best tutoring assistance 24x7 hours