1. Binit Mohanty Ketan Rajawat
Networks
Binit Mohanty
Ketan Rajawat

2. Recap – Layered Architecture
Application layer for GUI
Transport layer for Reliability
Networking layer for routing
MAC layer for Media access control
Physical layer for modulation

3. Ethernet Used in IITK LAN One medium - many users
IP address and Names - the DNS server
CSMA/CD – Carrier Sense Multiple Access with Collision Detection

4. Internetworking Eg: Connecting many LANs Each Network has Routers
Routers run some programs for finding the best path
Data in form of packets appended with source and destination address
Forwarded according to routing table

5. TCP – Transport Layer Limitations of PHY layer Solution : TCP
Packets are lost, reordered, duplicated
Congestion, overflow
Solution : TCP
Reliability by ACKs
Numbering of packets
Limit transfer rate according to congestion

6. TCP : Connection Establishment
Called a connection oriented protocol as opposed to a best effort protocol

7. TCP : Slow Start

8. TCP : Close Connection

9. TCP When would one not want TCP ?
When would reliability be at a lower priority ?
Streaming Data – streaming video
Energy efficiency – Sensor Networks

10. GSM – Global System for Mobile

11. GSM – channels Channels comprising of frequencies and time slots
Broadcast channel – network identity, frequency of operation
Control Channels –signal power, channel estimate, timing estimate, call origination
Traffic channels for voice