What are different application layer protocols?

Protocols are the set of rules that ensure communication between computers on a network. If we want communication between two systems, then it is necessary that they have a common language. To do this, we use protocols.

Application layer protocols form the top-most layer in the Open Communications Interconnection modelOSI model. This is the layer that enables the end-users to actually interact with the service provided.

List of protocols

• HTTP

HTTP stands for Hypertext Transfer Protocol. It is an Internet-based protocol used for sending and receiving webpages. It is an application layer protocol typically established over TCP, a transport layer protocol.

It is the most commonly used protocol at this layer that follows the client-server model.

• FTP

FTP stands for the File Transfer Protocol. This is the protocol that actually enables us to transfer files over a network using a client-server model. FTP promotes sharing files via remote computers with reliable and efficient data transfer. It allows users to upload, rename, move, copy, download, and delete files.

• SMTP

SMTP stands for Simple Mail Transfer Protocol. Email clients use this protocol for routing email messages over a network. It uses a store and forward mechanism to enable the movement of messages.

• DNS

DNS stands for Domain Name System. DNS translates domain names (which are human-readable) into IP addresses that a computer can understand, as they contain a mapping of domain names to their corresponding IP addresses.

DNS works in a hierarchical manner, with each level in the hierarchy responsible for mapping a subset of domains.

Example: A domain name like "educative.io" could be mapped to an IPv4 (IP address of 4 bytes) like this: 192.13.0.34.