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Q1. What is Grade of service and blocking probability? What are delay systemsintelecommunication networks?

Q2. Explain the basic architecture of digital switching systems. Explain the block diagram ofsubscriber’s line interface circuit for a digital exchange.

Q3. escribe the various signalling techni!ues. "ompare in#channel signallingwithcommon channel signaling$ which is more advantageous.

Q%. What is centrali&ed '("? what are its modes of operation? e)plain theworking of any one of these?

Q*. +)plain the architecture of '', and compare with seven#layer -'

architecture.

Q/. 0hrough two block diagrams e)plain the dierence between 'pace divisionandtime division switching.

Q,. +)plain the ""00 hierarchical structure of switching and routing using blockschematic.

Q. What are the advantages of ""' over in#channel signalling?

Q. +)plain crossbar e)change$ with all call processing steps and diagrams.

Q14. What is 0ra5c +ngineering? e6ne the term busy hour$ tra5c intensity andgradeof service.

Q11. +)plain the process of inter#register signalling.

Q12. +)plain the principles of operation of centrali&ed '(" and distributed '("andcompare their performance.

Q13. What is the dierence between message switching and packet switching$e)plain

typical packet switching network con6guration.

Q1%. With the help of a neat diagram e)plain the con6guration of a step by stepswitching system.

Q1*. 7 three stage network is reali&ed by using switching matrices of si&e p x sin stage1$ r x r matrices in stage 2 and s x p matrices in stage 3. 8sing the

8/18/2019 Electronic Switching Questions

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9ee:s probability graph show that the ;locking (robability for the three stagenetwork is given by

  Where k = s < p and α = nlet utili&ation factor

Q1/. iscuss grade of service. uring busy hour$ 1*44 calls were oered to agroup of trunks and calls were lost. 0he average call duration was 124 seconds."alculate the tra5c oered$ tra5c lost$ Grade of service and total duration ofcongestion.

Q1,. n a two stage network there are *12 inlets and outlets$ r=s=2%. f theprobability thata given inlet is active is 4.$ calculate>i@ 0he switching elements

ii@ 'witching capacityiii@ ;locking probability

Q1. e6ne congestion and grade of service. n a particular e)change duringbusy hour1244 calls were oered to a group of trunks$ during this time / calls were lost. 0heaverage call duration being 3 minutes "alculatei@ tra5c oered in erlangsAii@ tra5c lostiii@ grade of service andiv@ period of congestion

Q1. n a subscriber loop that contains a series resistance of 344 ohms toprotect the batteries in the e)change$ a normali&ed telephone draws 14 m7 andits standard input d.c. resistance is *4 ohms. "alculate the ma)imum distance atwhich a subscriber can get good speech reproduction if a cable of *2 ohms

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Q23. "alculate the ma)imum access time that can be permitted for the data andcontrolmemories in a 0' switch with a single input and single output trunk multiple)ing2*44 channels. 7lso$ estimate the cost of the switch and compare it with that ofasingle stage space division switch.

Q2%. "alculate the number of trunks that can be supported on a timemultiple)ed spaceswitch given that$ 32 channels are multiple)ed in each stream$ while the controlmemory access time is 144 ns and the bus switching and transferring time is144 nsper transfer.Q2*. Give the classification of switching system. Compare the switching techniques used in P!"..