Question

1 a) If the smallest MTU in the path from the source to the destination is 1,000 and the traffic consists of TCP segments what is the largest TCP data payload that can fit in a single IP datagram without having to fragment the IP datagrams?

b)What is the decimal value of the contents of the Ver field of the IPv4 header?

C)What is the maximum number of routers that an IPv4 packet can pass through on it way from source host to destination host

Answer 1

Solution:

(a)

Explanation:

Given,

=>MTU(Maximum transmission unit) = 1000 bytes

=>We know that the minimum header size of IPv4 header = 20 bytes.

=>As the data packet contains both header part as well as data or payload part so to find the maximum size of payload we need to consider minimum header size which is 20 bytes.

=>Maximum payload or data that can fit in a single IP datagram = 1000 -20 = 980 bytes.

(b)

Explanation:

=> The Ipv4 version or Ver field is of 4 bits.

=> 4 bits of IPv4 header = (0100)2

=>Converting into decimal:(0100)2 = (4)10

So the decimal value of Ver field of IPv4 header = 4

(c)

Explanation:

=>The time to live field of IPv4 header is used to tell the number of hops or routers a data packet can pass before it gets discarded.

=>Time to live(TTL) value is of 8 bits.

=>To calculate the maximum value we have to make all the bits as "1"

=> TTL value = (11111111)2

=>Converting into decimal: (11111111)2 = 255

So the maximum number of routers that an IPv4 packet can pass through on its way from host to destination = 255

I have explained each and every part with the statements attached to it.