Techinque of circuit switching & Message Switching
This
techinque is used in most of the wide area network . normally it is used in
modem communication over dial up telephone line . in this technique a temporary
communication connection is established between sending and reccving nodes on
requirement.
Whenever one
makes a call using standard telephone network , the caller is connected
to the dialed number through the connection of a number of switch in
between called and receiver phone and usin a transmission channel that can be
copper wire fiber link ratio link or a combination of these
. circuit switching relates to establishing a physical link between caller and receiver .
Once the
call has been established the data is almost transfer in real time .
When the
call is over and is terminated the switches and circuit are again available to
the other user .as there is always a limt on the availability of switches and
circuit .congestion can lead to blocking . buckling occurs when the link
between the source and distination can not be made due to the lack of
facilities and is indicated by busy signals . http://tktech-hub.blogspot.in
Circuit
switching when used with data transfer ensures that equipment at the source and
destination must be compatible interms of medems , bit rate protocol. posted
by - http://tktech-hub.blogspot.in
Messages switching – In message switchin no physical path
is established in advance between sender and reciver .in this switching the
data is not transfer in real time .it is used a store and forward network. in
message switching , switch in the network has message stored capability .when
the sender sends a block of data .
it is stored in the first switching office
called router and then forward later as a block to the next switching office.
The data is
transfer from router to router when it is convenient to do .message switching
can multiplex the data from different sources onto a common facility . in
comparison to circuit switching , message switching is more efficient because block is avoided by sorting
the data during busy time and then retransmitting it when the rush is over.
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