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E.G.S.PILLAY ENGINEERING COLLEGE, NAGAPATTINAM.
DEPARTMENT OF INFORMATION TECHNOLOGY
IT6601-MOBILE COMPUTING
16 MARK QUESTIONS
Unit-11. Cellular Systems.
Cellular systems for mobile communications implement SDM. Each transmitter, typically called a base station, covers a certain area, a cell. Cell radii can vary from tens of meters in buildings, and hundreds of meters in cities, up to tens ofkilometers in the countryside. The shape of cells are never perfect circles or hexagons.
Robustness
2. MAC. SDMA TDMA( Question-3) FDMA CDMA( Question-4)
3. TDMA.
Fixed TDM
The advantages of cellular systems. Higher capacity Less transmission power Local interface only
Classical Aloha
Slotted Aloha
Carrier sense multiple access
One improvement to the basic Aloha is sensing the carrier before accessing the medium.Demand assigned multiple access.
PRMA packet reservation multiple access
Reservation TDMA
Multiple access with collision avoidance Multiple access with collision avoidance (MACA) presents a simple scheme that solves
the hidden terminal problem, does not need a base station, and is still a random access Aloha scheme – but with dynamic reservation.
Request to send (RTSclear to send (CTS).
Polling Polling is a strictly centralized scheme with one master station and several slave stations.
The master can poll the slaves according to many schemes: round robin
Inhibit sense multiple accessThe base station only signals a busy medium via a busy tone (called BUSY/IDLE
indicator) on the downlink.
4. CDMA.Code division multiple access (CDMA) systems use exactly these codes to separate different users in code space and to enable access to a shared medium without interference. A code for a certain user should have a good autocorrelation2 and should be orthogonal to other codes.
Coding and spreading of data from sender A
Reconstruction of A’s data
5. Wireless cellular network:
Channel cell Cell sectoring Cell splitting Frequency reuse
Unit-2
1. IEEE 802.11 System and Protocol Architecture.(Nov 11&14)(Apr13)
2. Wireless Local Loop (WLL).(Nov-14)
Multichannel Multipoint Distribution Service (MMDS)(4 Marks)Used mainly between residential subscribers and small business.
Local Multipoint Distribution Service (LMDS)(4 Marks) Appeals to larger companies with greater bandwidth demands
3. IEEE 802.11 MAC.(Apr-May 2013)
4.
5. IEEE 802.11 Physical Layer.(Apr 13)
Unit-31. Mobile Services, Localization and Calling in GSM.
Mobile services: (4 Marks) Bearer services Tele services Supplementary services
Localization: (4 Marks)
MSISDN IMSI TMSI MSRN
Calling:(8 Marks)
2. System Architecture and Protocol Architecture in GSM.
System Architecture of GSM (8 Marks)
Protocol Architecture of GSM (8 Marks)
3. Handover and four types of scenario.
Carry over the signal from Old BTS to New BTS.Four possible handover scenarios in GSM:
Intra-cell handover Inter-cell, intra-BSC handover Inter-BSC, intra-MSC handover Inter MSC handover
Handover Scenario:
4. System Architecture and Protocol Architecture in GPRS.
System Architecture of GPRS (8 Marks)
Protocol Architecture of GRRS (8 Marks)
Unit-41. Mobile IP
IP Packet Delivery
Registration:
Registration request
Registration Reply
Agent Advertisement:
Agent Discovery
Agent Solicitation
Encapsulation&Decapsulation
Tunneling
2. Dynamic Host Configuration Protocol
Simplify the installation and Maintenance.
DHCP provide IP address, address of DNS server, subnet mask.
DHCP provide client server model.
3. Mobile Ad Hoc Routing Protocols
1. Destination Sequence Distance Vector
o Damping
o Sequence Number
2. Dynamic Source Routing
o Route Discovery
o Route Maintenance
3. Least Interference Routing
4. Indirect TCP, Snooping TCP and Mobile TCP.
Indirect TCP
Snooping TCP
Mobile TCP
5. Fast Retransmit / Fast Recovery, Transmission/Timeout Freezing, Selective
Retransmission and Transaction Oriented TCP.
Fast Retransmit / Fast Recovery
Transmission/Timeout Freezing
Selective Retransmission
Transaction Oriented TCP.
Unit-51. WAP-Wireless Application Protocol.
2. WAP Gateway
3. WAP protocols
Wireless Datagram Protocol Wireless Transport Layer Security Wireless Session Protocol
Wireless Transaction Protocol
WTP class o:
WTP class 1:
WTP class 2:
4. WTP: Wireless telephony application
WTA extends the basic WAE application model in several ways: Content push:
Access to telephony functions:
Repository for event handlers:
Security model
5. iMode and SyncML
imode:
SyncML