Question

10. In a network an IP address and prefix is given as 192.168.130.34/17. What is the subnet mask? (A) 0.0.127.255 (B) 255.255.0.0 (C) 255.255.128.0 (D) 0.0.2.34 11. In a network an IP address and prefix are given as 192.168.130.34/17. How many host addresses are there? (A) 34 (B) 32766 (C) 131072 (D) 2 12. One result of subnetting is that the size of the routing table in the routers is reduced (A) True (8) False 13. The port number is contained in the frame header. (A) True (8) False 14. The port number is contained in the segment header. (A) True (B) False 15. NAT, network address translation, is a fix to reduce the number of IP address required in a network (A) TRUE (B) FALSE 16. Draw a line to Match the message to the layer Segment Transport Layer Packet Data Link Layer Frame Network Layer 17. UDP is a connectionless protocol (A) TRUE (B) FALSE 18. TCP is a connectionless protocol (A) TRUE (B) FALSE 19. If a UDP segment is lost, reliability is guaranteed by the transport layer via the use of an acknowledgement protocol. (A) TRUE (B) FALSE 20. If a TCP segment is lost, reliability is guaranteed by the transport layer via the use of ar acknowledgement protocol. (B) TRUE (B) FALSE

Answer 1

10. /17 means 11111111.11111111.10000000.00000000. In decimal it is 255.255.128.0. So option c is correct.

11. /17 means 15 bits for hosts. So total IPs will be 2¹⁵ = 32768. Valid host IPs = 32768-2 = 32766. So option b is correct.

12. False. Subnetting does not reduce the size of routing table. Actual benefits of subnetting is improved network performance, less congestion, improved security, etc.

13. False. Frame header does not contain port number.

14. True. Port number is contained in segment header, both source and destination ports.

15. False. NAT uses translation between private to public IP, thereby connecting our private network to public network like internet. If we used PAT, only one public IP is used for whole private network. Hence, less public IPs required.

16. Segment----------Transport layer

Packet----------Network layer

Frame---------Data link layer