The document discusses the seven-layer OSI reference model. It describes each layer including the physical, data link, network, transport, session, presentation, and application layers. The physical layer deals with physical connections and converting data to bits. The data link layer converts bits to frames and provides tools for establishing connections. The network layer converts frames to packets and provides routing between networks. The transport layer reliably transmits packets and provides different classes of service. The session layer transmits data at time intervals and manages dialogs and tokens. The presentation layer translates data formats and performs encryption/compression. The application layer produces data and provides network services like file transfer and mail.

1. OSI MODEL
By
A. Bathsheba Parimala
Department of BCA and Networking

2. ISO PROPOSED OSI REFERENCE MODEL
• Consist of Seven Layer
• Physical Layer
• Data Link Layer
• Network Layer
• Transport Layer
• Session Layer
• Presentation Layer
• Application Layer

3. PHYSICAL LAYER
• Physical connection between network nodes
• Date are converted into bits
• Provides mechanical, electrical functional and procedural
characteristics

4. DATA LINK LAYER
• Bits are converted into frame
• Data reliability
• Provides tools to establish, maintain and release
• Functions
• Initialization
• Information segmentation
• Error control
• Data synchronization
• Flow control

5. DATA LINK LAYER PROTOCOL
• Character oriented protocol
• Bit oriented protocol
• HDLC protocol
• Information frame
• Superior frame
• Slide window protocol

6. NETWORK LAYER
• Frames converted into packet
• Provides service to the transport layer
• Congestion control
• Connecting multiple network
• Routing packet between source and destination

7. ROUTING PROTOCOLS
• RIP – Routing Information Protocol
• OSPF – Open Shortest Path First
• BGP – Border Gate Way Protocol

8. TRANSPORT LAYER
•Reliable to transmit the packet
•Efficient
•Cost effective
•End to end connection

9. TRANSPORT SERVICE
• Class 0: Simple class
• Class 1: Error recovering class
• Class 3: Multiplexing
• Class 4: Error recovering multiplexing class

10. TRANSPORT LAYER: SERVICE PRIMITIVE
•Listen
•Connection
•Send
•Receive
•Disconnect

11. SESSION LAYER
• Data are transmitted at time interval
• Dialog control
• Token management
• Synchronization
• Half duplex
• Activity management

12. PRESENTATION LAYER
•Also called as Translation Layer
•Transmit over the network
•Translation – ASCII to EBCDIC
•Encryption / Decryption
•Compression / Decompression

13. APPLICATION LAYER
• Also called as Desktop layer
• Produce the data to be transferred over the network
• Functions
• Network virtual terminal
• FTAM (File Transfer Access and Management)
• Mail Services
• Directory Services

14. THANK YOU