Network Engineering1ST semester December 2013

MTECH Information Technology 1^ST semester December 2013
Network Engineering
Part A(10 x 2 = 20)
1. Packet switching is more suitable than circuit switching for data communication network. Justify this statement.
2. Whether Ethernet is based on deterministic model or probabilistic model? Justify your answer.
3. State any 4 QoS metrics?
4. Available bandwidth of a channel is 10Mbps.10 users share this channel. All of them claim 2 Mbps consistently. Is it possible for the channel to accommodate all 10 users? Find the maximum number of user that can be accommodated at the current rate.
5. Write short notes on controlled load services in integrated services network.
6. What do you mean by ‘in profile’ and ‘out of profile’ in differentiated service network?
7. Why is it necessary to retain static routes even though dynamic routing protocol is in use?
8. Mention the purpose for which a bridge is used in local area networks.
9. Give examples for the protocols that maintain routing tables and the protocols that forward datagrams in a router.
10. State the major features of Software Defined Network.

PART B (5 x 16 =80)
11. (I) Consider network topology in Figure 1.

Explain how the packet will be routed from 1 to 6 if the networks assume datagram network organization and virtual circuit network organization. (10)
(II) Explain network externalities with an example. (6)

12. (A) (I). An ATM network has been designed and implemented so that the Peak Cell Rate is 64Kbps and the Sustained Cell Rate is 25 Kbps. For this network calculate Maximum Burst Size, Maximum Burst Duration and Burst Tolerance.
Hint:
MBS = PCR/53 bytes (unit is number of cells), T_MBS = MBS/PCR (unit is milliseconds or seconds) and BT = (MBS-1)((1/SCR)-(1/PCR)) (8)
(II). Differentiate best effort model and Guaranteed Service model. (8)
(OR)
(B). (I).Suppose a router has accepted flows with TSpecs shown in Table 1,described in terms of token bucket filters with token rate r packets per second and bucket depth of B packets. All flows are in the same direction and the router can forward one packet every 0.1 second.
Table 1

r	B
1	10
2	4
4	1

a) What is the maximum delay a packet might face?
b) What is the minimum number of packets from the third flow that the router would send over 2.0 seconds, assuming the flow sent packets ar its maximum rate uniformly? (8)
(II). Explain the Laissez Faire approach of providing QoS and compare its merits and demerits with reservation based approaches. (8)

13. (A). (I). Explain the ‘soft state’ and ‘receiver oriented approach’ followed by RSVP. (8)
(II). Draw the domain diagram of Differentiated Services network and explain the various components of the traffic conditioner at the ingress router.(8)
(OR)
(B). (I). Explain the assignment of labels and the maintenance of MPLS switching table with a sample topology. (8)
(II). Whether RTP is a transport layer protocol or application layer protocol or both? Analyze from different perspectives. (8)

14. (A). (I) Consider the network topology shown in figure 2.

Assume that the distance vector algorithm is followed to maintain the routing table and the metric used is delay. Delay for JA, JI, JH and JK are 8msec, 10msec, 12msec and 6msec respectively. J receives the distance vector from A, I, H and K (4 columns in the matrix as follows).

	A	I	H	K
A	0	24	20	21
B	12	36	31	28
C	25	18	19	36
D	40	27	8	24
E	14	7	30	22
F	23	20	19	40
G	18	31	6	31
H	17	20	0	19
I	21	0	14	22
J	9	11	7	10
K	24	22	22	0
L	29	33	9	9

Compute the new routing table of J to destinations A,B,C,D,E,F,G,H,I,J,K and L with corresponding delays and outgoing lines. (8)
(II) Draw the header diagram of RIPv2 and explain its various fields. (8)
(OR)
(B). (I). Consider the network topology shown in figure 3 using link routing.

Assume that link B-F fails. After the failure the following events take place in sequence.
a) Node H is added to the right with a connection to G
b) Node D is added to the left side with a connection to C
c) A new link DA is added.
The failed link B-F is restored .Describe what link state packets will flood back and forth. Assume that initial sequence number at all nodes is I, and that no packet time out. And that both the ends of a link use the same sequence number in their LSP for that link, Greater than any sequence number any used before. (8)
(II) Explain the following of OSPF
a) Areas and Backbone area (3)
b) Designated router and backup designated router (3)
c) Routing table and adjacency database (2)

15. (A) (I). Describe any one of the modern protocol stack for software defined networks. (8)
(II). Explain the terms neighbor, NLRI/Prefix, router ID, router path of BGP. Also explain the following message types of BGP: Open, Update, Keepalive and Notification. (8)
(OR)
(B) (I). Explain the data plane support for software defined networking. (8)
(II). Explain the architecture of a typical router with a neat diagram. (8)

Network Engineering Assessment -2 November -2013

Part A(2x3=6)
1) what is meant back pressure in  by congestion control ?Compare it with choke packet.
2)While providing QoS, at which stage will starvation occur?
3)Discuss about the need of soft state in Integrated services and list out the drawbacks of Integrated services.

Part B(2x10=20)
1)Discuss in detail about various models to provide Quality of Service in the internet.
2)What is the need of MPLS network? Explain in detail about its principle and mechanism.
       (Or)
Explain the polices available for improving the quality of service in BE and GS models.

Advanced computer architecture Assessment 1 (October 2013)

Part A

1) Protein string machine code has 4 days execution time on current machine doing integer instruction in 20% of time , doing I/O instruction in 35% of time and other instruction in the remaining time. Which is the better trade-off among the following two proposals?

(i) Compiler optimization that reduces the number of integer instructions by 25% (assume each integer instruction take same amount of time)
(ii)Hardware optimization that reduce the latency of each IO operation from 6µs to 5µs.

2) A computer architect need to design the pipeline of a new microprocessor. She has an example workload program with one million (10⁶ ) instructions. Each instruction takes 100ps (1ps = 10^-12  sec) to complete. How long does it take to execute this program in a non-pipelined processor? The current state-of-the-art microprocessor has about 20 pipeline stages. Assume it is perfectly pipelined. How much speedup will it achieve compared to no-pipelines processor?

3) How can a CPI < 1 be achieved? List the approaches used for it.

Part B

4) 

a) Explain Tomasulo's algorithm to overcome data hazzard using dymamic scheduling with neat diagram and an example code.

(9)

(OR)

b) Discuss the static and dynamic branch prediction techniques with suitable examples and diagrams

(9)

5)

Analyse data dependencies among the following statemens:

S1:   Load R1, 1024                    /R1 ← 1024/

S2:  Load  R2, M(10)                  /R2 ← Memory(10) /

S3: Add R1, R2                           /R1 ← (R1) + (R2) /

S4: Store M(1024) ,R1               /Memory(1024) ← (R1) /

S5: Store M((R2)) ,1024            /Memory(64) ← 1024/

Note that (Ri) means content of register Ri and Memory(10) contains 64 initially. Draw a dependence graph to show all the dependencies. Are there any resource dependencies if only one copy of each functional   unit is available in CPU?

(OR)

Consider the following code. If all istructions take 2 cycle latency ,unroll this loop to (i) twice and (ii) four times and show how a VLIW capable of two loads and two adds per cycle can use the minimum number of registers ,in the absence of pipeline interruptions and stall.

Loop: LW        R1,0(R2);

            ADDI    R5,R1,#1;

            SW       R1,0(R2);

            ADDI    R2,R2,#8;

            SUB      R4,R3,R2

            BNZ     R4,Loop

Advanced Databases assessment 1(October 2013)

Answer all questions
Part A(3 X 2 = 6)
1) Give the importance of aggregation in ER model.
2)What do you mean by an insertion anomaly in normalization?
3)State objective of distributed query processing using the semi join operation.

Part B(9 + 10 = 19)
4) Consider the following relations for a database that keeps track of student enrollment in courses and the books adopted for each course:
student(SSN,Name,Major,Bdate)
course(course#,Cname,Dept)
Enroll(SSN,Course#,Semester,Grade)
Book_Adoption(course#,Semester,Book_ISBN)
Text(Book_ISBN,Book_Title,Publisher,Author)

Draw an Extended ER diagram and convert in to relational schema diagram with all integrity constraints.Normalize the database upto 3NF.(9)

5)Using Hotel schema given below,draw an initial relational algebra query tree for the query and use the heuristic rules to optimize that tree into a more efficient final query tree.Discuss each step and state any transformation rules used in the process.

Hotel Schema:
Hotel (hotelNo,hotelName,city)
Room (roomNo,hotelNo,type,price)
Booking (hotelNo,guestNo,datefrom,daateTo,roomNo)
Guest (guestNo,guestName,guestAddress)

query
Select g.guestNo,g.guestName
from Room r,Hotel h,Booking b,Guest g
where h.hotelNo=b.hotelNo AND g.guestNo= b.guestNo AND
h.hotelNo = r.hotelNo AND h.hotelName = 'GPH' AND
dateFrom >= '1-Jan-13' AND dateTo <= '31-June-13'        (10)

 (OR)

6) Do all types of fragmentation using TEXT relation in Q.No 4              (10)

Advanced Data Structures and Algorithm Analysis Assessment 1(October 2013)

Part A
Answer in brief
1)Show that f(n) = (n +1)³ is O(n³).
2)Write the algorithm for Insertion sort and derive the time complexity for worst case.

Part B
Answer in detail.

1)

For the Above BST list out Inorder,Preorder and postorder traversal.
give pseudo code for performing Insertion and deletion in BST
2)List out the various asymptotic notations used to represent the complexity of an algorithm.State the signeficance of every notation.Compare and contrast the same.

Network Engineering Assessment 1(oct 2013)

Part A (3 X 2 =6)

1. What is known as bandwidth delay product ? what is the use of it?
2. What is the defference between circuit switching and packet switching?
3. To utilize the bandwidth effectively in a network what techniques can be used?

Part B Any two(19 Marks) question 2 is compulsory

1. What is switching? Explain in detail about different types of switching?(9)
2. With reference to data link layer what are the important control parameters to be addressed?Explain.(10)
3. Explain the architecture of TCP and OSI elaborately(9)

Software engineering methodologies 1 Assessment october 2013

Part A(2*3=6)

1. The Umbrella activities are not needed for software development process-justify
2. Define COTS,list its merits and demerits
3. Define:agility

Part B(Answer All)

1. Explain the spiral model with neat sketch and analyze its merits and demerits.(7)
2. consider the METRO bus service in chennai.you are the requirement analyst for automating MTC project.Explain the steps you will do to process the requirements and convert them into specifications.(12).