In: Computer Science
What’s true about shared and/or switched Ethernet LANs.
a. a full-duplex (FDX) shared Ethernet
LAN does not require CSMA/CD |
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b. switched Ethernet LANs do not experience data collisions because they operate as centralized/deterministic networks |
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c. each node connected to a shared Ethernet LAN must read destination addresses of all transmitted packets to determine if it belongs to them |
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d. switched Ethernet LANS are connected to nodes through dedicated links and therefore do not need to determine destination addresses of incoming packets |
Solution :
(a) a full-duplex (FDX)
shared Ethernet LAN does not require
CSMA/CD
= TRUE. Because there is no contention for use
of a shared medium, the multiple access algorithms (i.e., Carrier
Sense with Multiple Access and Collision Detect, or CSMA/CD) are
unnecessary.
(b)
switched Ethernet LANs do not experience
data collisions because they operate as centralized/deterministic
networks
= FALSE. Because in switched Ethernet, collisions
do not occur in the channel due to the presence of a dedicated
connection to each station. However, collisions may still occur in
a destination port if it receives frames from more than one port
simultaneously. And most importantly Ethernet is a decentralized
control using a non-deterministic access method.
(c) each node connected to
a shared Ethernet LAN must-read
destination addresses of all transmitted packets to determine if it
belongs to them.
=FALSE. A shared Ethernet LAN means that all
members of the network are contending for transmission of data onto
a single network (collision domain); individual members of a shared
network get only a percentage of the available network
bandwidth.
(d)
switched Ethernet LANs are connected to
nodes through dedicated links and therefore do not need to
determine destination addresses of incoming packets.
= TRUE. In Switched Ethernet LANs, each station
gets a dedicated connection. Switches make sure that each packet is
delivered only to the host to which it is addressed.