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Friday, 28 February 2014

Basic civil engineering -model question paper for B.E/B.Tech Engineering


1 (a) What are the qualities of an ideal preservative? (4 Marks)
(b) Explain the tests to which bricks are generally subjected. (6 Marks)
(c) What are the properties of good lime? (4 Marks)
(d) Explain the various laboratory tests for cement. (6 Marks)
2 (a) What do you mean by proportioning of concrete? What are its various methods? Describe them in brief. (8 Marks)
(b) What are the various characteristics of good timber to be used in engineering works? (4 Marks)
(c) Give the classification of mortar based on the binding agent. (4 Marks)
(d) What are the different types of varnishes? (4 Marks)
3 (a) Compare load bearing walled structure and framed structure. (6 Marks)
(b) What are the characteristics of a pile foundation? Describe very briefly the various types of piles generally used for foundation. (6 Marks)
(c) Compare brick masonry and stone masonry. (4 Marks)
(d) Describe briefly the construction of brick and stone flooring. (4 Marks)
4 (a) Describe the methods which are used to make the flat roofs water-proof. (4 Marks)
(b) What points should be considered while fixing the positions of doors and windows? (4 Marks)
(c) Define scaffolding. What are the different types of scaffolding? (6 Marks)
(d) What are the different cost effective construction techniques generally used? (6 Marks)
5 (a) Describe various types of tapes commonly used in surveying. (4 Marks)
(b) What are the various methods by which one can draw a perpendicular to a chain line from a point? Discuss. (4Marks)
(c) Explain the term bearing. What are different systems of designation of bearings? Explain each system with neat sketches. (8 Marks)
(d) The distance between two stations was measured with a 20 m chain and found to be 2500 m. The same was measured with a 30 m chain and found to be 2460 m. If the 20 m chain was 5 cm too short, what was the error in the 30 m chain? (4 Marks)
6 (a) What are the advantages and disadvantages of plane table survey? (4 Marks)
(b) What are the common difficulties generally faced in leveling? How will you overcome each of them? (6 Marks)
(c) What are the functions of a theodolite? Draw a neat sketch of theodolite showing its different parts. (6 Marks)
(d) The back sight reading on a staff held vertical on the floor is 3.58 m and the fore sight when the staff is held inverted with its bottom touching the beam at the roof is 2.355 m. If the R.L of the floor is 85.325 m, find the R.L. of the beam. (4 Marks)
7 (a) Write a short note on the use of contour maps for engineering purposes. (4 Marks)
(b) Write a short note on planimeter. (4 Marks)
(c) Define a prismoid. Derive the prismoidal formula. What is the limitation of prismoidal formula? (6 Marks)
(d) The following perpendicular offsets were taken from a chain line to a hedge at 10 m intervals:
3.10, 4.20, 5.35, 6.45, 7.15, 8.25, 7.95 and 5.20 m.
Find the area by (i) Trapezoidal rule and (ii) Simpson’s rule. (6 Marks)
8 (a) What are the general guidelines for planning of earthquake resistant buildings? (4 Marks)
(b) Discuss behavior of different building materials during fire. Wat are the various fire protection systems? (8 Marks)
(c) Describe how rehabitation and reconstruction operations are to be managed after a disaster. (4 Marks)
(d) Write short note on use of various I.S. codes in design of buildings. (4 Marks)

Manufacturing process-I -model question paper for B.E/B.Tech/M.E/M.Tech Engineering


1 (a) List the advantages and limitations of casting process. (4 Marks)
(b) What is distortion allowance? Explain the need for the same. (4 Marks)
(c) With a neat sketch, explain the working of Jolt-Squeeze type moulding machine. (6 Marks)
(d) List different types of cores. Draw representative figures for each type. (6 Marks)
2 (a) What is the principle of Thixocasting process? (4 Marks)
(b) What are the zones in Cupola? With a neat sketch explain the same. (6 Marks)
(c) Compare how gates and risers are removed in carbon steel castings and cast iron castings. (6 Marks)
(d) Explain the factors which contribute to casting defects. (4 Marks)
3 (a) Write a note on NDT using ultrasonic waves. (6 Marks)
(b) Explain two methods of moisture content determination. Which one of them is preferred in shop floor? (6 Marks)
(c) What are chills? Explain the need for chills. (4 Marks)
(d) Explain degassing of aluminium alloy by using hexachloroethane tablet and N2 gas purging. (4 Marks)
4 (a) What is the effect of grain refinement on mechanical properties? (4 Marks)
(b) Explain the effect of inoculation on mechanical properties (4 Marks)
(c) Briefly explain the foundry characteristics of cast iron, white iron and steel. (6 Marks)
(d) With neat sketches bring out the need for design for minimum casting stress. (6 Marks)
5 (a) What is pouring time? Explain its significance. (4 Marks)
(b) Explain Chvorinov’s rule. (4 Marks)
(c) Draw a neat flow chart of sand preparation plant and discuss how it can be mechanized. (6 Marks)
(d) Explain how computers can be used in a foundry. (6 Marks)
6 (a) List down the advantages, limitations and applications of welding. (6 Marks)
(b) What is the function of flux in gas welding? (4 Marks)
(c) Differentiate between DC and AC arc welding. (6 Marks)
(d) What is residual stress in welding? Explain. (4 Marks)
7 (a) What problems are associated with resistance welding of tin, lead and antimony metals? (4Marks)
(b) With a neat sketch explain how microstructure varies in a medium carbon steel. Show all the regions. (6 Marks)

(c) Explain the process details of ultrasonic welding and electron beam welding. (6 Marks)

(d) List down different types of welding defects. (4 Marks)

8 (a) What is brazing? What are the steps in brazing process? (8 Marks)

(b)Give the application of brazing. (4 Marks)

(c) What is wetting? Explain how it affects soldering. (4 Marks)

(d) List down types of soldering. (4 Marks)

Physical metallurgy- model question paper for B.E/B.Tech/M.E/M.Tech Engineering


1(a) Show that for a face centered cubic crystal packing fraction is 74%. (5 Marks)

(b) Explain the method of determination of Miller indices. (5 Marks)

(c) Explain the differences between a chemical compound, an ordered solid solution and a random solid solution. (6 Marks)

(d) Calculate the spacing between edge dislocations in a tilt boundary in iron, when the angle of misorientation between the subgrains is 2o. (4 Marks)

2 (a) State and explain Gibbs phase rule. (4 Marks)

(b) Explain why a eutectic composition does not show coring, whereas a solid solution does. (6 Marks)
(c) Draw heating curves for a proeutectic and a eutectic composition. (6 Marks)
(d) Determine the atomic percentage of Carbon in mild steel containing 0.2 weight percentage Carbon. (4 Marks)
3 (a) Explain Fick’s laws. (6 Marks)
(b) Differentiate between homogeneous nucleation and heterogeneous nucleation. What is overall transformation rate? (6 Marks)
(c) List the methods available for refining the grain size of a casting. (4 Marks)
(d) What is the purpose of tempering a quenched steel? (4 Marks)
4 (a) Differentiate between T-T-T diagrams and C-C-T diagrams. (8 Marks)
(b) Explain the process austenitization. (4 Marks)
(c) Distinguish between austempering and martempering. (4 Marks)
(d) Explain how quenching carburized steel introduces residual compressive stresses at the surface. (4 Marks)
5 (a) Write a note on slip and twinning. (4 Marks)
(b) Explain in detail different methods used for strengthening metals against yield. (8 Marks)
(c) What is Griffith’s criterion? Explain. (4 Marks)
(d) If the grain size of mild steel is changed from ASTM No.8 to 13 by microalloying additions, estimate the increase in yield strength. (4 Marks)
6 (a) Explain the working of a Galvanic cell. (5 Marks)
(b) Write notes on polarization and passivation. (6 Marks)
(c) What are the general characteristics of stress corrosion cracking? (5 Marks)
(d) A pit in a 18/8 stainless steel exposed to sea water grows to a depth of 50 mm in a year. To what average current density does this correspond? (4 Marks)
7 (a) Write a note on AISI-SAE classification of steels. (4 Marks)
(b) Define plastic anisotropy parameter. What is its significance? (6 Marks)
(c) What are the general properties required for good tools? (4 Marks)
(d) Distinguish between maraging steels and trip steels. (6 Marks)
8 (a) What is a Schaeffler diagram? (4 Marks)
(b) Whar are superalloys? Explain in detail three types of superalloys. (8 Marks)
(c) Describe the composition and heat treatment of (α+β) titanium alloys for optimum mechanical properties. (4Marks)
(d) Describe the role of hard particles, soft matrix and insoluble metals in the functioning of a bearing alloy. (4 Marks)

Thursday, 27 February 2014

Powerplant technology- model question paper for B.E/B.Tech/M.E/M.Tech Engineering


1 (a) Write a note on subcooled liquids. (4 Marks)
(b) Draw and explain T-s diagram of an internally irreversible superheat Rankine cycle. Explain the working of a closed type feedwater heaters with drains cascaded backward. (8 Marks)
(c) What is cogeneration? Explain economics of cogeneration. (4 Marks)
(d) A water pump compresses saturated water at 1 to 2500 psia. The pump efficiency is 0.70. Find the ideal and actual pump and the water exit temperature. (4 Marks)
2 (a) Differentiate between straight-tube boiler and bent-tube boiler. (6 Marks)
(b) Explain the different stages of pulverizing process. (6 Marks)
(c) Explain any two forms of biomass conversion. (4 Marks)
(d) A 200 m high 4 m diameter stack emits 1000 kg/s of 100oC gases into 5oC air. The prevailing wind velocity is 50 km/hr. The atmosphere is in a condition of neutral stability. Calculate the height of the gas plume by two methods. (4 Marks)
3 (a) Using a neat velocity diagram explain the working of a two stage reaction turbine. (6 Marks)
(b) Write a note on turbine losses. (6 Marks)
(c) Explain the processes involved in a water makeup system. (4 Marks)
(d) A single effect evaporator receives motive steam at 7 bars and 180oC and pretreated raw water at 9 bars and 16oC. It has 123 m2 of heat transfer area. Calculate the mass flow rates of motive steam and vapour produced in kilograms per second. Ignore the pressure drop in the evaporator. (4 Marks)
4 (a) Explain the mechanisms by which wet-cooling towers dissipate heat rejected by the plant to the environment. (6 Marks)
(b) What is a fill? What are the two types of fill? (4 Marks)
(c) Show that the efficiency of an ideal Brayton cycle at the optimum pressure ratio is a function of minimum and maximum temperatures only, and independent of the working fluid. (6 Marks)
(d) A helium gas turbine cycle has compressor and turbine polytropic efficiencies of 0.8 and 0.9 and pressure ratios of 2.5 and 2.4 respectively. The compressor has one stage of intercooling and turbine has one stage of reheat. The cycle has a generator with 85% effectiveness. The cycle minimum and maximum temperatures are 100 and 2000oF respectively. Calculate (a) the cycle efficiency, and (b) the cycle power for a helium mass flow rate of 200 lbm/s. (4 Marks)
5 (a) Explain nuclear fission and fusion. (4 Marks)
(b) Write and explain Maxwell distribution law. (4 Marks)
(c) Explain in detail different methods to control a nuclear reactor. (8 Marks)
(d) Radium 226 decays into radon gas. Compute the decay constant and the initial activity of 1 g of radium 226. The atomic mass is 226.0245 amu. (4 Marks)
6 (a) Draw core cross section of PWR reactor. Explain. (4 Marks)
(b) What are pebble-bed reactors? (4 Marks)
(c) Write a note on Clinch River breeder reactor project. (8 Marks)
(d) A large commercial gas-cooled fast breeder reactor using a plutonium-uranium mixed oxide fuel has a breeding ratio of 1.5 and a compound doubling time of 6 years. Estimate the average neutron flux in the reactor. Assume that the fuel in the core represents 80 % of the reactor fuel inventory. (4 Marks)
7 (a) Geothermal sources are of three kinds. Explain. (6 Marks)
(b) Explain using a neat figure, the working of a liquid dominated single flash steam system. (6 Marks)
(c) Differentiate between geothermal-preheat hybrid systems and fossil-superheat hybrid systems. (4 Marks)
(d) What is land surface subsidence? Explain. (4 Marks)
8 (a) Write a note on heliostats. (4 Marks)
(b) Write expressions for lift force and drag force. Explain the terms. (4 Marks)
(c) Write notes on thermal sensible energy storage and latent heat energy storage. (8 Marks)
(d) An ocean wave power system of the float type uses a 25 cm thick float in 2m waves that have 60 m wavelength. The cylinder has a diameter of 1 m. The compressor pressure ratio is 10. The air is at 1 atm at 10oC. Calculate the power produced by the turbine if the compressor-turbine system has an efficiency of 76 percent of ideal. (4 Marks)

Tuesday, 25 February 2014

Basic Thermodynamics- model question paper for B.E/B.Tech Engineering


1 (a) Define thermodynamic system and point out the difference

between closed system, open system and isolated system. 6 Marks)

(b) Describe briefly the working of constant volume gas

 thermometer. (4 Marks)

(c) Explain equality of temperature. (4 Marks)

(d) A Celsius scale and a Fahrenheit scale are immersed in a fluid.

Calculate the temperature of a fluid when,
(a) the numerical reading is identical in both the thermometers.
(b) the Fahrenheit reading is numerically twice that of the Celsius

 reading.
Calculate the values in R and K. (6 Marks)

2 (a) Give the thermodynamic definition of work and heat.

 Establish the relation between the two. (6 Marks)

(b) Differentiate between isochoric and isenthalpic processes. 

(6 Marks)

(c) What is a polytropic process? Explain. (4 Marks)

(d) A shaft rotates at a rate of 100 rpm against a constant torque of 1000 Nm. Calculate the power required to rotate the shaft. Also calculate the work required to rotate the shaft through 50 revolutions. (4 Marks)
3(a) Derive an expression for the first law of thermodynamics applied to a closed system. Show how it gives a conception of internal energy. (6 Marks)
(b)Deduce an expression for the work done when a system undergoes a quasi-static hyperbolic process. (6 Marks)
(c) Explain why Cp is greater than Cv. (4 Marks)
(d) A tank containing a fluid is stirred by a paddle wheel. Heat is transferred from the tank at the rate of 6000 kJ/hr. The work required is 3 kW. Determine the change in internal energy of the system in one hour. (4 Marks)
4 (a) What are the limitations of first law of thermodynamics? (4 Marks)
(b) Write a note on perpetual motion machine. (4 Marks)
(c) Classify reversible process and explain briefly with example and neat sketch. (6 Marks)
(d) Three Carnot engines are connected in series and the combination of these series engines operates between 727oC and 27oC. The work produced by these engines are in the ratio of 5:4:3. Calculate the intermediate temperature. (6 Marks)
5 (a) Define change of entropy. Show that change in entropy is a measure of irreversibility. (6 Marks)
(b) Write a brief note on degradation of entropy. (4 Marks)
(c) Explain the principle of entropy production. (6 Marks)
(d) A heat source at 1000 K transfer heat at the rate of 8373.6 kJ/min to a system at 400 K. The heat sink temperature is 300 K. Assuming that these temperatures remain constant, find the entropy production accompanying the heat transfer. (4 Marks)
6 (a) Define second law efficiency for expansion process or heating. (4 Marks)
(b) Write the expression for irreversibility of closed system and open system. (4 Marks)
(c) Explain the term available and unavailable energy. When does the system become dead state? (6 Marks)
(d) Determine the irreversibility per kg of Freon 12 flow, associated with an expansion valve. Freon = 12 enters at 1.2 MPa, at 30oC and is expanded to 100 kPa. (6 Marks)
7 (a) Draw TV and TP diagrams for a pure substance and indicate all the salient features. (6 Marks)
(b) Describe with a neat sketch how you determine the dryness fraction of wet steam using a throttling calorimeter. (6 Marks)
(c) 0.5 kg of steam with initial dryness of 0.7 is heated at a constant pressure of 8 bar till the volume is tripled. Determine the final temperature, heat and work transfer. (4 Marks)
(d) A closed rigid vessel contains 1.68 kg of liquid water and 1.35 kg of water vapour at a pressure of 300 kPa. Heat transfer to the water causes the water to reach a pressure of 800 kPa. Determine the internal energy change during the process. (4 Marks)
8 (a) State Gibbs Dalton's law. (4 Marks)
(b) Explain Boyle's law and Charle's law and deduce the equation of perfect gases. (6 Marks)
(c) Define critical properties and reduced properties. (4 Marks)
(d) A mixture of 1 kg of Oxygen and 2 kg of Nitrogen occupies volume of i cubic meter at temperature 300 K. Assuming perfect gas behaviour, determine the following properties of the mixture: (a) specific volume, (b) pressure and (c) relative molecular mass. (6 Marks)

Wednesday, 19 February 2014

Astrophysics-Model question paper for MSc/PhD

1(a) Compare the advantages and disadvantages of reflecting and refracting telescopes. (6 Marks)
(b) Why short waves are used for radio transmission at far-off places? (4 Marks)
(c)Using Planck's blackbody radiation law, obtain Wien's law and Rayleigh-Jeans law. (6 Marks)
(d) An object moves towards the observer with a velocity of 1000 km/s. What will be the shift of the H-alpha line in its spectrum. (4 Marks)
2(a) Define luminosity of a star. Derive the relationship between the luminosity and the absolute magnitude of a star. (6 Marks)
(b) Show that the altitude of the pole is equal to the latitude of the place of the observer. (6 Marks)
(c) Define spectroscopic parallax. (4 Marks)
(d) Compute the solar constant if the distance between the sun and earth is 1.6 AU. (4 Marks)
3(a)Explain the concept of grey atmosphere. (4 Marks)
(b) Explain blanketing effect in stars. (4 Marks)
(c)Define equivalent width and total half-width of a spectral line. (6 Marks)
(d) Calculate the bound free absorption coefficients per atom of the neutral hydrogen at n =1 and n=2 levels. Calculate the corresponding absorption coefficients for a singly ionised helium atom. (6 Marks)
4(a)An RR Lyrae  star is observed to have an apparent magnitude +20 in a globular cluster. Calculate the distance of the cluster. (4 Marks)
(b) Discuss some important astrophysical information that were obtained by the event of 1987A supernova. (6 Marks)
(c) What observational features of T Tauri stars lead us to believe that they still are contracting towards the main sequence. (6 Marks)
(d) A star has a luminosity equal to that of the sun. Its surface temperature is 2500 K. Compute the radius of the star in terms of the radius of the sun. (4 Marks)
5(a)Explain how the colour-magnitude diagrams are used to calibrate the galactic distance scale. (6 Marks)
(b) On what evidences can we conclude that stellar associations are extremely young objects? (4 Marks)
(c) Define dilution factor. What is its value in an average emission nebula. (4 Marks)
(d) Describe a method by which the temperature of the central star of a planetary is determined. What kind of temperatures are obtained for these stars? (6 Marks)
6(a) Discuss the present understanding of the velocity distribution of the interstellar clouds. Give the various distribution laws and comment on their merits and demerits. (6 Marks)
(b) Discuss Kahn's model of interstellar cloud collisions and calculate the rate of kinetic energy dissipated by the process. (6 Marks)
(c) List the different nuclear reactions which may be present in the sun. Discuss the solar neutrino puzzle. (4 Marks)
(d) Assuming that 20% of the mass of the sun undergoes transmutation from H to He during its lifetime, calculate how long the sun will shine maintaining its present luminosity. (4 Marks)
7(a) Discuss the general nature of the primary and secondary pulses of a pulsar. (4 Marks)
(b) What do you know about the Galactic distribution of pulsars? Are all the observed pulsars Galactic? Give reasons to support your views. (6 Marks)
(c) Draw a diagram of the rotation curve of the Galaxy and obtain a polynomial in the radial distance r that fits the rotation curve fairly well. (6 Marks)
(d) Write a note on cosmic rays. (4 Marks)
8 (a) Explain the terms density wave, dispersion ring, dispersion orbit and Lindblad resonance. (4 Marks)
(b) Explain how we can compute the masses of elliptical galaxies? What simplifying assumptions are made for such computations? What are the sources of uncertainty? (6 Marks)
(c) Distinguish between strong and weak radio galaxies. (4 Marks)
(d) Using Newtonian mechanics, show that the deceleration parameter q is related to the total energy E of the universe and that the universe is flat when E=0. What is then the density in the universe? (6 Marks)

Strength of materials-Model question paper for B.E/B.Tech engineering

1(a)Distinguish between normal stress and shear stress. (4 Marks)
(b)Define coefficient of thermal expansion. What is the value for steel and copper? (4 Marks)
(c)Define the terms simple shear, Poisson's ratio and volumetric strain. (6 Marks)
(d) A steel flat of thickness 10 mm tapers uniformly from 60 mm at one end to 40 mm at other end in a length of 600 mm. if the bar is subjected to a load of 60 kN, find its extension. Take E = 200000 MPa. What is the percentage error if average area is used for calculating extension? (6 Marks)
2(a) Differentiate between bending moment diagram and a shear force diagram. (6 Marks)
(b) Mention some commonly encountered statically determinate beams. (4 Marks)
(c) A girder 6m long rests on two supports with equal overhangs on either side and carries a uniformly distributed load of 30 kN per metre run over the entire length. Calculate the overhangs if the maximum bending moment, positive or negative, is to be as small as possible. Draw SF and BM diagrams for the double overhang beam. (10 Marks)
3(a) Write a note on simple bending theory. (6 Marks)
(b) Derive a relation between moment and radius of curvature. (4 Marks)
(c) What are flitched beams? Mention one example. (4 Marks)
(d)A cantilever beam of span 1m has rectangular cross-section of size 200 mm x 400 mm. Determine the concentrated load which placed at the free end produce shear stress of intensity 1.5 N per square mm. Hence compute maximum bending stresses in the cross-section at the fixed end of cantilever. (6 Marks)
4(a)Derive the differential equation for deflection. What is flexural rigidity? (8 Marks)
(b)Write the steps involved in Macaulay's method. (4 Marks)
(c) A simply supported beam of span L is subjected to equal loads W/2 at each of 1/3 rd span points. Find the expressions for deflection under the load and at mid span. (8 Marks)
5(a) Write a note on the assumptions made in developing the theory of pure torsion. (4 Marks)
(b) Define polar modulus. (4 Marks)
(c) What are shear keys? Draw a figure and explain its working. (6 Marks)
(d) What percentage of strength of a solid circular steel shaft 100 mm diameter is lost by boring 50 mm axial hole in it? Compare the strength and weight ratio of the two cases. (6 Marks)
6(a) Show that when a material is subjected to shearing stresses and direct stress in one direction, the major and minor principal stresses are of opposite nature. (4 Marks)
(b)Explain the construction of Mohr's circle. (6 Marks)
(c) A shear force of 40 kN and a bending moment of 20 kN-m act at a certain cross section of rectangular beam 100 mm wide and 200 mm deep. Compute the direction of the principal stresses at a point 20 mm below the top surface. (6 Marks)
(d) Write a note on strain gauges. (4 Marks)
7(a) Differentiate between longitudinal stress and circumferential stress. (4 Marks)
(b) Prove that when fluid is admitted in a wire wound cylinder, final stresses are obtained by algebraically adding initial stresses and stresses due to fluid. (6 Marks)
(c) What is shrinkage allowance? Explain. (4 Marks)
(d) A pipe of 400 mm internal diameter and 100 mm thickness contains a fluid at a pressure 80 N per square mm. Find the maximum and minimum hoop stresses across the section. Also sketch the radial and hoop stress distribution across the section. (6 Marks)
8(a) What are the limitations of Euler's theory? (4 Marks)
(b) Write and explain Rankine's formula. (4 Marks)
(c) Write a note on Beltrami and Haigh's theory. (6 Marks)
(d) A thick steel cylinder with an internal diameter 200 mm has to withstand an internal fluid pressure of 40 N per square mm. Calculate the thickness of the metal by using maximum principal stress theory. (6 Marks)

Wednesday, 5 February 2014

Computer networking-Model question paper for B.E/B.Tech Engineering


1(a) Explain 'client program' and 'server program'. Does a server program request and receive services from a client program? (6 Marks)
(b) List six access technologies. Classify each one as residential access, company access, or mobile access. (6 Marks)
(c)What is the difference between a POP and a NAP? (4 Marks)
(d)What is instant messaging? Are there any products that allow you to access an instant messaging service through a handheld device? (4 Marks)
2(a) What is the differe between network architecture and application architecture. (4 Marks)
(b) Why is it said that FTP sends control information “out-of-band”? (4 Marks)
(c)What is an overlay network in a P2P file sharing system? Does it include routers? What are the edges in the overlay network?How is the Guntella overlay network created and maintained? (8 Marks)
(d)Write a note on Apache web server. (4 Marks)
3(a) An application developer might choose to run an application over UDP rather than TCP. Describe why? (6 Marks)
(b) Write a note on TCP delay modeling. (5 Marks)
(c) Explain any two selective repeat sender events. (4 Marks)
(d)Suppose host A sends two TCP segments back to back to host B over a TCP connection. The first segment has sequence number 90. The second has sequence number 110. How much data is in the first segment? Suppose that the first segment is lost but the second segment arrives at B. In the acknowledgement that host B sends to host A, what will be the acknowledgement number? (5 Marks)
4(a) What are three most important network layer functions in a circuit switched network? (6 Marks)
(b) Describe how packet loss can occur at output ports. (4 Marks)
(c)Compare and contrast the IPv4 and IPv6 header fields. Do they have any fields in common? (6 Marks)
(d)Suppose datagrams are limited to 1500 bytes, including header, between source host A and destination host B. Assuming a 20-byte IP header, how many datagrams would be required to send an MP3 consisting of 4 million bytes? (4 Marks)
5 (a) Describe polling and token passing protocols using the analogy of cocktail party interactions. (6 Marks)
(b) Write short notes on MAC address space, IPv4 address space and IPv6 address space. (6 Marks)
(c) Graph the efficiency of slotted ALOHA and pure ALOHA as a function of p for N=100. (4 Marks)
(d)Explain the frame structure of Gigabit Ethernet. (4 Marks)
6 (a) Discuss the methods that are available to authenticate users for 802.11 networks. (6 Marks)
(b) Explain in detail how the RTS threshold works. (6 Marks)
(c)What effect will mobility have in mobile IP on end-to-end delays of datagrams between the source and the destination. (4 Marks)
(d)List 4 products on the market today that provide a Bluetooth or 802.15 interface. (4 Marks)
7 (a) What is meant by interactivity for streaming sored audio/video? What is meant by interactivity for real time interactive audio/video? (6 Marks)
(b) Why is a pcket that is received after its scheduled playout time considered lost? (4 Marks)
(c)Explain the difficulties associated with the Intserv model and perflow reservation of resources. (6 Marks)
(d)How is RTSP similar to HTTP? Does RTSP have methods? Can HTTP be used to request a stream? (6 Marks)
8 (a) Differentiate between a passive and an active intruder. (4 Marks)
(b) In what way does a public-key encrypted message digest provide a better digital signature than using the public-key encrypted message. (4 Marks)
(c)Suppose that an intruder could insert DNS messages into and remove DNS messages from the network. Give three scenarios showing the problems that such an intruder could cause. (6 Marks)
(d) What is meant by an SNMP engine? What is an important difference between a request response message and a trap message in SNMP? (6 Marks)