1. CS 350
Chapter-2

2. Advantages layered Model

3. Please Do Not Throw Sausage Pizza Away
Application
Provides a user interface
Presentation
Presents data, handles processing such as data encryption, compression
Session
Keeps different applications’ data separate (simplex, half duplex, and full duplex)
Transport
Provides reliable or unreliable delivery, performs error correction before retransmit (Conn-oriented, flow control)
Network
Provides logical addressing, which routers use for path determination
Data Link
Combines packets into bytes and bytes into frames, provides access to media using MAC address, performs error detection not correction
Physical
Moves bits between devices, specifies voltage, wire speed, and pin-out of cables

4. Transport Connection-Oriented Communication Windowing Acknoledgement
Virtual circuit
Sequencing
Acknowledgement
Flow control
Windowing
Acknoledgement

5. Networking Data packets Route-update packets Network address Interface
Metric

6. Routers Do not forward broadcast or multicast
Use IP address to forward packet to the next hop
Use access list, created by admin, to control security on the types of packets allowed to enter or exit
Can provide layer-2 bridging functions, and route through the same interface simultaneously
Layer-3 device, provide connection between VLAN
Provide QoS

7. The Data Link Layer Media Access Control (MAC)
Contention media access – first come first serve
Logical Link Control (LLC)
Encapsulation
Flow control
Sequencing

8. IEEE 802 – LAN/MANs 802.2 --- LLC 802.3 --- CSMA/CD
– Wireless LAN
WiMAX

9. Physical Layer
Bit patterns
Encoding bits
Interfaces
Physical topology

10. Encapsulation