CS702(C) Unit 3 Wireless LAN, Mobile IP and Ad Hoc Networks study material for RGPV CSE 7th Semester. Learn WLAN transmission medium, MAC problems, hidden and exposed terminals, IEEE 802.11, spread spectrum, Mobile IP, agent advertisement, tunneling and ad hoc routing protocols like AODV, DSDV, DSR and ZRP.
Unit 3 explains wireless LAN concepts, MAC layer issues, IEEE 802.11 architecture, Mobile IP and ad hoc network routing. This unit is highly important because questions from hidden terminal, exposed terminal, IEEE 802.11, Mobile IP and routing protocols are commonly asked in exams.
Understand WLAN transmission medium, MAC problems, hidden/exposed terminals and IEEE 802.11.
Learn Mobile IP goals, agent advertisement, discovery, registration and tunneling.
Study ad hoc networks, traditional IP routing comparison, AODV, DSDV, DSR and ZRP.
Complete syllabus-based topics of Wireless & Mobile Computing Unit 3.
Wireless LAN allows devices to communicate without physical cables using radio frequency communication.
WLANs commonly use radio waves, infrared and spread spectrum techniques for wireless communication.
Wireless MAC faces problems such as hidden terminal, exposed terminal, near-far terminal, collisions, interference and mobility issues.
Hidden terminal problem occurs when two stations cannot hear each other but transmit to the same receiver, causing collision at the receiver.
Exposed terminal problem occurs when a station unnecessarily avoids transmission because it senses another transmission nearby, even though its transmission would not cause interference.
Near-far terminal problem occurs when a nearby strong signal makes it difficult for a receiver to detect a weaker far signal.
In infrastructure mode, wireless devices communicate through an access point connected to a wired network.
An ad hoc network is a temporary wireless network where nodes communicate directly without fixed infrastructure.
IEEE 802.11 architecture includes stations, access points, basic service set, extended service set and distribution system.
IEEE 802.11 protocol architecture defines physical layer and MAC layer functions for wireless LAN communication.
The physical layer handles signal transmission, frequency, modulation and spread spectrum techniques.
Spread spectrum spreads signal over a wide frequency band to improve reliability and reduce interference.
MAC management handles association, authentication, roaming, synchronization and power management in WLANs.
Power management helps mobile devices save battery by allowing sleep and active modes.
Wireless LAN security protects communication from unauthorized access, eavesdropping and attacks.
Mobile IP allows mobile nodes to move between networks while maintaining continuous IP connectivity.
The main goals of Mobile IP are transparency, compatibility, security, scalability and continuous connectivity.
Foreign agents and home agents advertise their services so mobile nodes can discover and register with them.
Registration allows a mobile node to inform its home agent about its current location or care-of address.
Tunneling encapsulates packets and forwards them from the home network to the mobile node’s current network.
Ad hoc routing discovers and maintains routes dynamically because nodes can move frequently.
Traditional IP routing assumes fixed infrastructure, while ad hoc routing handles dynamic topology and node mobility.
Ad hoc On-Demand Distance Vector is a reactive routing protocol that creates routes only when needed.
Destination Sequenced Distance Vector is a proactive routing protocol based on distance vector routing.
Dynamic Source Routing is a reactive protocol where complete route information is stored in packet headers.
Zone Routing Protocol is a hybrid routing protocol combining proactive routing within zones and reactive routing between zones.
Hidden Terminal: Do stations ek dusre ko nahi sun paate, but same receiver ko transmit karte hain.
Exposed Terminal: Station unnecessary wait karta hai because nearby transmission detect hota hai.
IEEE 802.11: Wireless LAN standard.
Mobile IP: Moving device ko continuous IP connectivity deta hai.
AODV: Reactive routing protocol.
DSDV: Proactive routing protocol.
ZRP: Hybrid routing protocol.
| Topic | Expected Frequency | Importance |
|---|---|---|
| Hidden Terminal Problem | Very High | ⭐⭐⭐⭐⭐ |
| Exposed Terminal Problem | Very High | ⭐⭐⭐⭐⭐ |
| IEEE 802.11 Architecture | Very High | ⭐⭐⭐⭐⭐ |
| Spread Spectrum | High | ⭐⭐⭐⭐ |
| Mobile IP | Very High | ⭐⭐⭐⭐⭐ |
| Agent Advertisement & Registration | High | ⭐⭐⭐⭐ |
| Tunneling Techniques | High | ⭐⭐⭐⭐ |
| Ad Hoc Routing | Very High | ⭐⭐⭐⭐⭐ |
| AODV, DSDV, DSR | Very High | ⭐⭐⭐⭐⭐ |
| ZRP | High | ⭐⭐⭐⭐ |
Wireless LAN allows devices to communicate using wireless signals instead of cables.
It occurs when two devices cannot hear each other but transmit to the same receiver, causing collision.
IEEE 802.11 is a standard for Wireless LAN communication.
Mobile IP allows a mobile device to move between networks while maintaining IP connectivity.
AODV is a reactive ad hoc routing protocol that creates routes only when needed.
ZRP is a hybrid ad hoc routing protocol combining proactive and reactive routing methods.