Do routers have IP addresses? If so, how many?
Ans: Yes routers have ip address and mostly routers have two ip address .The first router
interface is wide area network which have public ip address. The second one is local area
network and this side contain private ip address.
Suppose there are three routers between a source host and a destination host. Ignoring
fragmentation, an IP datagram sent from the source host to the destination host will travel over
how many interfaces? How many forwarding tables will be indexed to move the datagram from
the source to the destination?
Ans: Here in this scenario source host forward the ip data gram to link interface one. It reaches
at the interface2 and router1 receive it and output datagram to its wlan interface which is
interface3.seconf router receive it from nterface4 and forward to interface5 .in the same way
third router receive it via interface6 and forward to interface7 and destination host receives it at
interface8. So there are 8 interfaces and three forwarding tables will be indexed.
Suppose datagrams are limited to 1,500 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 5 million bytes? Explain how you computed your answer.
Ans: MP3 file size = 5 million bytes. Assume the data is carried in ip header is 20bytes for source
and 20 bytes for destination .Then each datagram can carry 1500-40=1460 bytes of the MP3 file.
Number of datagrams required =total file size/datagram size
=((5 * 106) / 1460)=3425 datagrams
Consider the following network. With the indicated link costs, use Bellman-Ford and Dijkstra’s
shortest-path algorithm to compute the shortest path from x to all network nodes.
Ans: Dijkstra
Step
0
1
2
3
4
5
6
N
x
xv
xuv
xvuw
xvuwy
xvuwyt
xvuwytz
D(t),P(t)
inf
7,v
7,v
7,v
7,v
7,v
7,v
D(u),P(u)
inf
6,v
6,v
6,v
6,v
6,v
6,v
D(v),P(v)
3,x
3,x
3,x
3,x
3,x
3,x
3,x
D(w),P(w)
6,x
6,x
6,x
6,v
6,v
6,v
6,v
D(y),P(y)
6,x
6,x
6,v
6,v
6,v
6,v
6,v
D(z),P(z)
8,x
8,x
8,x
8,x
8,x
8,x
8,x
The specific IP address of Stanford University: 140.142.0.0-140.142.255.255
It is denoted by the notation: 140.142.0.0/16.
The specific IP address of New York University: 128.238.0.0 -128.238.255.255
It is denoted by the notation:128.238.0.0/16
The specific IP address of Chicago University: 171.64.0.0-171.67.255.255
It is denoted by the notation: 128.64.0.0/24
No, the whois services cannot be used to determine with certainty the geographical location of a
specific IP address.