The OSI Model is a conceptual and logical model that characterizes network communication utilized by systems open to communication and interconnection with different systems. We will below understand various OSI layers and its functions.
The Open System Interconnection or OSI reference model also characterizes a logical network and adequately depicts the computer packet transfer by utilizing different protocols.
The recent Internet did not depend on Open System Interconnection, yet the less difficult TCP/IP model. Notwithstanding, the seven OSI layers model is still broadly utilized, as it envisions and imparts how networks work and help isolate and troubleshoot networking issues.
The list of OSI layers in tabular format is under:
|Layer||Name of Layer|
Sender ↓ Receiver ↑
|Layer 4||Transport||Heart of OSI|
The physical layer encourages you to determine the physical and electrical determinations of the data connection.
Physical OSI Layer: Sending cable → Bitstream → Receiving Cable
Physical Layer Functions:
The data link layer is very much like the network layer, aside from the data link layer encourages data to move between two devices on a similar network.
Data-Link OSI Layer: Frame Creation → Transport → Transfer Frames Between Network Nodes
Data-Link Layer Functions:
It works for the transmission of data from one host to the next situated in various networks.
Network OSI Layer: Packets Creation → Transport → Packets Assembly
Network Layer Functions:
It deals with the delivery and error checking of data packets.
Transport OSI Layer: Segmentation → Transport → Reassembly
Transport Layer Functions:
This layer is answerable for the establishment of connection, support of sessions, verification and guarantees security.
Session OSI Layer: Session of Communication
Session Layer Functions:
It permits you to determine the form in which the data is to trade between the two communicating entities.
Presentation OSI Layer: Encryption → Compression → Translation
Presentation Layer Functions:
The Application Layer (7 layers of OSI Model) is the lone layer that straightforwardly interacts with data from the client.
Application OSI Layer: Return Content in Required Format → ← Website
Request Content → ← Website
Application Layer Functions:
|Layer Name Protocols||Protocols|
|Application Layer Protocol||SNMP, POP3, FTP, HTTP, SMTP|
|Presentation Layer Protocol||TLS, SSL, ASCH, MPEG|
|Session Layer Protocol||SAP, NetBIOS|
|Transport Layer Protocol||UDP, TCP|
|Network Layer Protocol||MPLS, ARP, IPSEC, ICMP, IPV6, IPV5|
|Data-Link Layer Protocol||Fibre Cable, ATM, Frame Relay, PPP, RAPA, and so on.|
|Physical Layer Protocol||ISDN, 100BaseTX, RS232|
|Application Layer||Application Proxy Firewalls|
|Network Layer||Router, Layer 3 Switch|
|Data-Link Layer||NICs, Bridges, Switches, Encryption Devices|
|Physical Layer||Modems, Repeater, Hubs, NICs, Connectors, Cables|
|Application Layer||Version Rollback Attack, Send Mail, FTP, and Network File System Bugs|
|Session Layer||Portmapper Exploits and Remote Procedure Call Worms|
|Transport Layer||Sequence Number Prediction, SYN Flooding, and Routing Information Protocol Attacks|
|Network Layer||IP Smurfing and Other Address Spoofing Attacks|
|Data-Link Layer||Wired Equivalent Privacy Attacks|
The types of OSI layers are a conceptual and logical model that determines network communication which is utilized by frameworks open to communication and interconnection with different frameworks.
OSI layers causes you to comprehend communication over a network.
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