– The datagram is checked for corruption and the correct address. – If all is ok the Network Access Layer extracts the data and passes it to the designated protocol. Wikipedia articles on the Internet, packet switching and IP addresses. How many control bits will be used to control data transfer. This section provides general and specific information pertaining to networking, including an overview of network concepts and detailed discussion of popular network protocols. Another advantage of TCP/IP is that the IP packets don’t have to be sent to the same type of server.
- The task of finding how to get a datagram to its destination is referred to as “routing”.
- Note that the interface between TCP and IP is fairly simple.
- There are a range of different protocols to do different jobs on the network.
- SMTP is used by mail servers to send and receive mail from all other mail servers around the world.
- In fact many of the details depend upon the particular implementation.
We aim to help you reflect on your own learning and help you feel more clear about your progress through clarifying what is expected of you in both formative and summative assessments. This module introduces the fundamental concepts of different Internet and LAN protocols that developed for computer networks. Please be aware crossgrid.org that resources have been published on the website in the form that they were originally supplied. This means that procedures reflect general practice and standards applicable at the time resources were produced and cannot be assumed to be acceptable today. A network protocol is an agreed way of communicating over a network.
4 Packet Switching
It also makes sure that the data arrives, resending datagrams where necessary. But for a question that fits in a single datagram, we don’t need all the complexity of TCP to do this. If we don’t get an answer after a few seconds, we can just ask again. For applications like this, there are alternatives to TCP.
Ethernet is a family of related protocols which deal with how data is sent along ethernet cables – it isn’t a single protocol. There are lots of parts to the ethernet protocol family, which include how the hardware is managed, as well as how data is sent and received and how data collisions are managed. When we use our web browser to access a web page, it is very unlikely that we know the IP address of the web-server hosting the required web page.
Since they are both doing file transfers, one end of the connection involves the well-known port number for FTP. The only thing that differs is the port number for the program that the users are running. Generally, at least one end of the connection asks the network software to assign it a port number that is guaranteed to be unique. Normally, it’s the user’s end, since the server has to use a well-known number.
Every network utility has to be able to make such queries, since this is now the official way to evaluate host names. Generally utilities will talk to a server on their own system. This server will take care of contacting the other servers for them. This keeps down the amount of code that has to be in each application program. The domain system is particularly important for handling computer mail. There are entry types to define what computer handles mail for a given name, to specify where an individual is to receive mail, and to define mailing lists.