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Revision for Chapter 3-4In Explicit Reservation (Reservation Aloha), collisions is possible in:

ALOHA modeReserved mode Both modes

A starts sending to B, C does not receive this transmission. C also wants to send something to B and senses the medium. The medium appears to be free, the carrier sense fails. C also starts sending causing a collision at B.

Hidden terminalsExposed terminalsNear and far terminalsMultinumbering in GSM is an example of:

Bearer ServicesTelematic ServicesSupplementary Services

In GSM, which of the following is NOT part of the Operation Subsystem (OSS)

Operation and Maintenance Center (OMC)Authentication Center (AUC)Home Location Register (HLR)Equipment Identity Register (EIR)

In Base Station Subsystem (BSS) of GSM:

Each Base Station Controller (BSC) is connected to only one Base Transceiver Station (BTS).Each Base Station Controller (BSC) is connected to many Base Transceiver Stations (BTS).Each Base Transceiver Station (BTS) is connected to many Base Station Controllers (BSC).

The International Mobile Subscriber Identity (IMSI)

Uniquely identifies the mobile deviceUniquely identifies the Subscriber Identity Module (SIM card)Used to hide the identity of the user for security purposes

Which of the following is considered an internal handover:

transferring a call between cells within the same BSS transferring a call between cells within the same MSCtransferring a call between cells within different MSCs

Which of the following is used to transmit user data

Traffic channels (TCH)Common control channel (CCCH)Dedicated control channel (DCCH)

Handover decision is based on:

Received signal strengthDistance of MS from BTSDrops below power budget marginAll of the above

The VLR contains data from:

HLR of the same provider HLR of other providersBoth A and B are correctPower control is very important in wireless networks to solve:

hidden terminal problemexposed terminal problemnear & far terminals problem

Devise a frequency division duplex scheme that allocated the frequency band 500 600 MHz to 200 users. What will be the bandwidth available for each user? Assume a guard of 20 MHz is required between the uplink and downlink connections

200 KHz400 KHz500 KHz