Answer to Question #215319 in Computer Networks for Christiane BACHIR

Question

1. For each IPv4 network prefix given (with length), identify which of the subsequent IPv4 addresses are part of the same subnet.

(a). 10.0.130.0/23: 10.0.130.23, 10.0.129.1, 10.0.131.12, 10.0.132.7

(b). 10.0.132.0/22: 10.0.130.23, 10.0.135.1, 10.0.134.12, 10.0.136.7

(c). 10.0.64.0/18: 10.0.65.13, 10.0.32.4, 10.0.127.3, 10.0.128.4

(d). 10.0.168.0/21: 10.0.166.1, 10.0.170.3, 10.0.174.5, 10.0.177.7

(e). 10.0.0.64/26: 10.0.0.125, 10.0.0.66, 10.0.0.130, 10.0.0.62

 

2. Convert the following subnet masks to /k notation, and vice-versa:

(a). 255.255.240.0

(b). 255.255.248.0

(c). 255.255.255.192

(d). /20

(e). /22

(f). /27

 

3. Suppose an Ethernet packet represents a TCP acknowledgment; that is, the packet contains an IPv4 header with no options and a 20-byte TCP header but nothing else. Is the IPv4 packet here smaller than the Ethernet minimum packet size, and, if so, by how much? What if the packet is IPv6 with no extension headers?

Answer 1

1 a) 10.0.130.23 and 10.0.131.12

b) 10.0.135.1 and 10.0.134.12

c) 10.0.65.13 and 10.0.127.3

d)10.0.170.3 and 10.0.174.5

e) 10.0.0.125 and 10.0.0.66

2 a) /20

b) /21

c) /26

d) 255.255.240.0

e) 255.255.252.0

f) 255.255.255.224

3.

Yes, its smaller by 64-20 = 44byte

IPv6 has packet size of 16bytes.