Engineering Questions with Answers - Multiple Choice Questions
MCQs on ATM & Frame Relay
ATM and frame relay are ________
a) virtual circuit networks
b) datagram networks
c) virtual private networks
d) virtual public networks
Explanation: ATM and frame relay are transmission modes in which information is transferred through electric circuit layer as packets. ATM has fixed packet size and frame relay has variable packet size.
ATM uses _______________
a) asynchronous frequency division multiplexing
b) asynchronous time division multiplexing
c) asynchronous space division multiplexing
d) asynchronous amplitude division multiplexing
Explanation: ATM uses a constant data stream consisting of transmission cells to transmit information in a fixed division of time. The packet size remains fixed.
ATM standard defines _______ layers.
Explanation: The three layers are physical layer, ATM layer and application adoption layer. The physical layer corresponds to the physical layer, ATM layer corresponds to the data link layer and the AAL layer corresponds to the network layer of the OSI model.
ATM can be used for ________
a) local area network
b) wide area network
c) campus area network
d) networks covering any range
Explanation: ATM is a connection oriented network for cell relay which can be implemented for networks covering any area. It uses Time Division Multiplexing and supports voice, video and data communications.
An ATM cell has the payload field of __________
a) 32 bytes
b) 48 bytes
c) 64 bytes
d) 128 bytes
Explanation: An ATM field contains a header and a payload. The header is of 5 bytes and the payload is of 48 bytes. The size of the header remains fixed.
Frame relay has error detection at the ______
a) physical layer
b) data link layer
c) network layer
d) transport layer
Explanation: The Frame Relay header contains an 8-bit Header Error Control field (HEC). The HEC field contains an 8-bit CRC which is used for error control.
Virtual circuit identifier in frame relay is called ______
a) data link connection identifier
b) frame relay identifier
c) cell relay identifier
d) circuit connection identifier
Explanation: The Data Link Connection Identifier is 10-bit virtual circuit identifier. It is used to assign frames to the specified Permanent Virtual Circuits or Switched Virtual Circuits.
Frame relay has _______
a) only physical layer
b) only data link layer
c) only network layer
d) both physical and data link layer
Explanation: The physical layer is guided by the protocols recognized by the ANSI. The data link layer supports the simplified core functions specified by the OSI model.
In frame relay networks, extended address is used _______
a) to increase the range of data link connection identifiers
b) for error detection
c) for encryption
d) for error recovery
Explanation: Extended address is indicated by the last bit of every address byte in the DLCI. It specifies whether the byte is the last in the addressing field. It is used to increase the range of data link connection identifiers.
What is FRAD in frame relay network?
a) FRAD assembles and disassembles the frames coming from other protocols
b) FRAD is used for modulation and demodulation
c) FRAD is used for error detection
d) FRAD is used for error recovery
Explanation: FRAD stands for Frame Relay Assembler/Disassembler. It converts packets into frames that can be transmitted over Frame Relay Networks. It operates at the physical layer.