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1)FTP uses two well-known TCP ports: ________is used for the controlconnection, and ______ is used for the data connection
a) Port 21, port 20 b) port 20, Port 21
c) Port 23, Port 25 d) Port 23, Port 21
2)TELNET is an abbreviation for ______________
a) Telephone Network b) Television Network
c) Terminal Net OS d) Terminal Network
3)TELNET uses the______________________ system to encode characterson the local system.
a) MVT b) NVT
c) NVTS d) NMV
4)Which of the following well-known TCP ports are used by FTP ?
a) 20,21 b) 19,20
c) 80,80 d) 20,80
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11) In TFTP block of less than _________ signals the end of file.
a) 256 bytes b) 512 bytes
c) error d) FIN packet
12) To deal with zero window size advertisement _____________ timer isused.
a) Persistence Timer b) Keepalive Timer
c) TIME-WAIT d) Retransmission Timer
13) ______________ used when amount of work required to handle arequest is unknown.
a) Concurrent server b) Iterative server
c) Parallel server d) Passive server
14) ______________ used when amount of work required to handle arequest is known.
a) Concurrent server b) Iterative server
c) Parallel server d) Passive server
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15)________ is bidirectional communication abstraction via whichapplication can send or receive data.
A)Port no B) Socket
C) IP address D) all of above
16)_________ socket is reliable socket.
A)SOCK_STREAM B) SOCK_DGRAM
C)SOCK_RAW D) None of above
17) In _____ least significant bit is at lowest address.
A) Little Endian B) BIG Endian
18)
A socket system call returns an integer called ___________whichuniquely defines the created socket.
a) Socket number b) Socket descriptor
c) Socket address d) All
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1) What is socket? Draw and explain socket structure.
(5 marks Nov 2010)
A socket is bidirectional communication abstraction via
which application can send or receive data.
Socket=IP Address + port no
Types of socket
Header file #include <sys/types.h>
#include <sys/socket.h>
struct sockaddr_in {
uint8_t sin_len;
sa_family_t sin_family;in_port_t sin_port;
struct in_addr sin_addr;
char sin_zero[8];
};
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2) Describe following system calls 1) connect 2)accept
(5 marks Nov 2010)
int accept (int sid , struct sockaddr *addrPtr , int *lenPtr )
int connect(int sid ,struct sockaddr *addrPtr,int len )
1) Header files2) Socket structure
3) Side of execution
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3) Describe Connectionless iterative server concept
(5 marks may 2011)
• Definition of iterative server
• Connectionless properties
• Working
•diagram
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4) Explain Socket system call with example
( 5 marks may 2011)
a) Definition of socket
b) Syntax of socket system call
c) Header files required
d) Meaning of each parameter
e) Example
socket(AF_INET,SOCK_STREAM,0)
socket(AF_INET,SOCK_DGRAM,0)
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TCP client server interaction.
socket()
bind()
listen()
accept()
write()
read()
read()
close()
socket()
connect()
write()
read()
close()
connection establishment
data request
data r eply
TCP Client
TCP Server
Blocks until
connection from client
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6) Describe connection establishment and termination in TCP
( 10 marks Nov 2011)
a) Features of TCP
b) Three way handshaking
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b)Four-step connection termination
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7) Describe sliding window protocol. What is silly window
syndrome? Describe its solutions? (10 marks Nov 2010)
• Sending window
• Receiving window
• Piggybacking
Window is in three statesa) closing
b) opening
c) shrinking
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8) List and explain different types of timers
( 5 Marks nov 2011)
a) Persistence Timer
b) Retransmission timer
c) Keepalive timer
d) TIME-WAIT timer
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9) What is UDP ? Draw and explain user datagram format
( 5 marks Nov 2010)
•Includes three sections
• UDP header
• data
• Pseudoheader
– Part of header of IP packet.
– Ensures that if IP header is corrupted that the user datagram is not to be submitted to
wrong host.
20 Bytes 8 Bytes
IP header UDP header UDP data
UDP datagram
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9) Describe in congestion control in detail
( 10 marks nov 2010)
• BECN-Backward explicitly congestion notification
• FECN-Forward explicitly congestion notification
A. Monitor the system .
– detect when and where congestion occurs.
B. Pass information to where action can be taken.
C. Adjust system operation to correct the problem.
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Retransmission Policy
Window policy
Acknowledgment Policy
Discarding Policy
Admission Policy
Back Pressure
Choke packet
Implicit signaling
Explicit signaling
Congestion Control
Open Loop Closed Loop
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Traffic Shaping The Leaky Bucket Algorithm
(a) A leaky bucket with water. (b) a leaky bucket with packets.
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The Token Bucket Algorithm
(a) Before. (b) After.
5-34
Token bucket allows some burstiness (up to the number of tokenthe bucket can hold)
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