GATE CS Fragmentation and IP Addressing, IPv4, CIDR questions

If an IP network uses a subnet mask of $255.255.240.0$, the maximum number of IP addresses that can be assigned to network interfaces is $\_\_\_\_$. (answer in integer)

A packet with the destination $\text{IP}$ address $145.36 .109 .70$ arrives at a router whose routing table is shown. Which interface will the packet be forwarded to? …

Suppose a message of size $15000$ bytes is transmitted from a source to a destination using IPv4 protocol via two routers as shown in the figure. Each router has a defined maximum transmission unit (MTU) as shown in the figure, including IP header. The number of fragments that will be delivered to the destination is _________. (Answer in integer)

​​​A machine receives an $IPv4$ datagram. The protocol field of the $IPv4$ header has the protocol number of a protocol $X$. Which ONE of the following is NOT a possible candidate for $X$?

​​​​​Consider a network that uses Ethernet and $IPv4$. Assume that $IPv4$ headers do not use any options field. Each Ethernet frame can carry a maximum of $1500$ bytes in its data field. A UDP segment is transmitted. The payload (data) in the UDPO segment is $7488$ bytes. Which ONE of the following choices has the CORRECT total number of fragments …

Which of the following fields is/are modified in the $\text{IP}$ header of a packet going out of a network address translation $\text{(NAT)}$ device from an internal network to an external network?

Consider sending an $\text{IP}$ datagram of size $1420$ bytes (including $20$ bytes of $\text{IP}$ header) from a sender to a receiver over a path of two links with a router between them. The first link (sender to router) has an $\text{MTU}$ (Maximum Transmission Unit) size of $542$ bytes, while the second link (router to receiver) has an …

​​​​​Which of the following statements about $\text{IPv4}$ fragmentation is/are TRUE?

​​​​Which of the following fields of an $\text{IP}$ header is/are always modified by any router before it forwards the $\text{IP}$ packet?

​​​​​Which one of the following $\text{CIDR}$ prefixes exactly represents the range of $\text{IP}$ addresses $10.12 .2 .0$ to $10.12 .3 .255$?

Suppose in a web browser, you click on the $\textsf{www. gate-2023.in}\; \text{URL}$. The browser cache is empty. The $\text{IP address}$ for this $\text{URL}$ is not cached in your local host, so a $\text{DNS}$ lookup is triggered (by the local $\text{DNS}$ server deployed on your local host) over the $3$-tier $\text{DNS}$ hierarchy in an …

The forwarding table of a router is shown below. …

Consider routing table of an organization’s router shown below: …

An organization requires a range of IP address to assign one to each of its $1500$ computers. The organization has approached an Internet Service Provider (ISP) for this task. The ISP uses CIDR and serves the requests from the available IP address space $202.61.0.0/17$. The ISP wants to assign an address space to the organization which will minimize the …

Consider three machines M, N, and P with IP addresses $100.10.5.2, \: 100.10.5.5$, and $100.10.5.6$ respectively. The subnet mask is set to $255.255.255.252$ for all the three machines. Which one of the following is true?

Consider an IP packet with a length of $4,500\;\text{bytes}$ that includes a $20\text{-byte}\;\textsf{IPv4}$ header and a $40\text{-byte}$ TCP header. The packet is forwarded to an $\textsf{IPv4}$ router that supports a Maximum Transmission Unit (MTU) of $600\;\text{bytes}$. Assume that the length of the IP header in all the outgoing fragments of …

The maximum number of $\textsf{IPv4}$ router addresses that can be listed in the record route (RR) option field of an $\textsf{IPv4}$ header is______.

An IP datagram of size $1000$ $\text{bytes }$arrives at a router. The router has to forward this packet on a link whose MTU (maximum transmission unit) is $100$ $\text{bytes }$. Assume that the size of the IP header is $20$ $\text{bytes }.$ The number of fragments that the IP datagram will be divided into for transmission is________.

Which of the following fields of an IP header is NOT modified by a typical IP router?

$\text{Host A}$ sends a $\text{UDP}$ datagram containing $8880\text{ bytes}$ of user data to $\text{host B}$ over an $\text{Ethernet LAN}.$ Ethernet frames may carry data up to $1500\text{ bytes (i.e. MTU = 1500 bytes)}.$ Size of $\text{UDP}$ header is $8\text{ bytes}$ and size of $\text{IP}$ header is $20\text{ bytes}.$ There is no …