What are the protocols in the OSI model?
The OSI model is the reference model for developing network protocols. In this tutorial, we will discuss the example protocols for all OSI model layers. When a protocol is developed according to the OSI model, the first thing is, which OSI layer will provide the service to the new protocol? The layer selection will be based on the functionality and network requirements.
For example, if you want to develop a network protocol that needs only routing functionality for IP packets. Then this will be above the Network layer of the OSI model. If it needs connection-oriented delivery of messages, the new protocol will be above the transport layer of the OSI model. Following is a list of protocols and the OSI layer they belong to.
DHCP OSI layer :
DHCP is an application layer protocol. In an actual implementation, DHCP works over TCP/IP protocol. The full form is the Dynamic Host Control Protocol. When a network connection comes up. A network device needs an IP address to work in a computer network. The computer connecting to the computer network works as a DHCP client. It requests the server to get the IP. You might have seen this while configuring a Windows machine’s IP address for the Ethernet or LAN card. The internet router works as a DHCP server in this case.
ARP OSI layer :
ARP stands for Address Resolution Protocol. It resolves an IP address to the MAC address of the Ethernet card. ARP is the data link layer protocol in the OSI model.
DNS OSI layer :
This is a domain name system. It is an application layer protocol.
ICMP OSI layer:
It works as a user of the IP layer. ICMP routes protocol messages to the remote end using the IP layer protocol. This provides a service to the end-user, so it is an application layer protocol.
UDP OSI layer:
UDP is a transport layer protocol. This is a datagram protocol where no connection is set up. Not reliable, but suitable for real-time delivery. It is a transport layer protocol.
TCP OSI model:
It is another example of a layer four (transport layer ) protocol. It is a relational protocol.
ss7 and OSI model:
SS7 itself has many layers. Following is the tabular mapping of ss7 protocol layers with the OSI model.
| SS7 Layers | OSI layers |
| MTP1 | Physical Layer |
| MTP2 | Data Link Layer |
| MTP3 | Network Layer |
| SCCP | Transport Layer |
| TCAP, ISUP | Session Layer and Presentation Layer |
| MAP, INAP, Camel | Application Layer |
Telnet and OSI layer:
Telnet is an application layer protocol of the OSI model. It is for remote operations over the computer network. Uses TCP/IP for the transport of telnet protocol messages.
SIP and OSI layer:
Sip is a session initiation protocol used in the VoIP network. This belongs to the application layer of OSI.
IP and OSI layer:
IP is Internet Protocol. It is a layer three protocol example of the OSI model. IP uses the services of the data link layer and provides services to the transport layer. The transport layer examples are SCTP, TCP, UDP, etc.