Network Layer

Which one of the following protocols may need to broadcast some of its messages?

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)

Consider a file of size 4 million bytes being transferred between two hosts connected via a path consisting of three consecutive links of bandwidth $2 \mathrm{Mbps}, 500 \mathrm{kbps}$, and 1 Mbps , respectively. All pro...

An ISP having an address block 202.16.0.0/15 assigns a block of 6000 IP addresses to a client, using the classless internet domain routing (CIDR) super-netting approach. Which of the following address blocks can be assig...

Consider the routing protocols given in List-I and the names given in List-II: List - I List - II (i) Distance vector routing (a) Bellman-Ford (ii) Link state routing (b) Dijkstra For matching of items in List-I with tho...

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 (d...

A packet with the destination IP address 145.36.109.70 arrives at a router whose routing table is shown. Which interface will the packet be forwarded to? Subnet Address Subnet Mask (in CIDR notation) Interface 145.36.0.0...

Consider the entries shown below in the forwarding table of an IP router. Each entry consists of an IP prefix and the corresponding next hop router for packets whose destination IP address matches the prefix. The notatio...

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

Which of the following statements about IPv4 fragmentation is/are TRUE?

Node X has a TCP connection open to node Y. The packets from X to Y go through an intermediate IP router R. Ethernet switch S is the first switch on the network path between X and R. Consider a packet sent from X to Y ov...

Which of the following fields of an IP header is/are always modified by any router before it forwards the IP packet?

Consider sending an IP datagram of size 1420 bytes (including 20 bytes of 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 MTU (Maximum...

Consider a network path P—Q—R between nodes P and R via router Q. Node P sends a file of size $10^6$ bytes to R via this path by splitting the file into chunks of $10^3$ bytes each. Node P sends these chunks one after th...

Which one of the following CIDR prefixes exactly represents the range of IP addresses 10.12.2.0 to 10.12.3.255?

Which of the following statements is/are INCORRECT about the OSPF (Open Shortest Path First) routing protocol used in the Internet?

The forwarding table of a router is shown below. Subnet Number Subnet Mask Interface ID 200.150.0.0 255.255.0.0 1 200.150.64.0 255.255.224.0 2 200.150.68.0 255.255.255.0 3 200.150.68.64 255.255.255.224 4 Default 0 A pack...

Consider routing table of an organization's router shown below : Subnet number Subnet mask Next hop 12.20.164.0 255.255.252.0 R1 12.20.170.0 255.255.254.0 R2 12.20.168.0 255.255.254.0 Interface 0 12.20.166.0 255.255.254....

Consider a 100 Mbps link between an earth station (sender) and a satellite (receiver) at an altitude of 2100 km. The signal propagates at a speed of 3 $$\times$$ 10 8 m/s. The time taken (in milliseconds, rounded off to...

Consider two hosts P and Q connected through a router R. The maximum transfer unit (MTU) value of the link between P and R is 1500 bytes, and between R and Q is 820 bytes. A TCP segment of size 1400 bytes was transferred...

An organization requires a range of IP addresses 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 fr...

Consider the following statements about the functionality of an IP based router. I. A router does not modify the IP packets during forwarding. II. It is not necessary for a router to implement any routing protocol. III....

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 $$4,500$$ bytes that includes a $$20$$-byte $$IPv$$$$4$$ header and a $$40$$-byte $$TCP$$ header. The packet is forwarded to an $$IPv4$$ router that supports a Maximum Transmiss...

For a host machine that uses the token bucket algorithm for congestion control, the token bucket has a capacity of 1 megabyte and the maximum output rate is 20 megabytes per second. Tokens arrive at a rate to sustain out...

Which one of the following protocols is NOT used to resolve one form of address to another one?

An IP datagram of size 1000 bytes arrives at a router. The router has to forward this packet on a link whose MTU (maximum transmission unit) is 100 bytes. Assume that the size of the IP header is 20 bytes. The number of...

In the network 200.20.11.144/27, the fourth octet (in decimal) of the last IP address of the network which can be assigned to a host is ________.

Two hosts are connected via a packet switch with 10 7 bits per second links. Each link has a propagation delay of 20 microseconds. The switch begins forwarding a packet 35 microseconds after it receives the same. If 1000...

Two hosts are connected via a packet switch with $${10^7}$$ bits per second links. Each link has a propagation delay of $$20$$ micro-seconds. The switch begins forwarding a packet $$35$$ microseconds after it receives th...

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

Host A sends a UDP datagram containing 8880 bytes of user data to host B over an Ethernet LAN. Ethernet frames may carry data up to 1500 bytes (i.e. MTU = 1500 bytes). Size of UDP header is 8 bytes and size of IP heard i...

Host A (on TCP/IPv4 network A) sends an IP datagram D to host B (also on TCP/IPv4 network B). Assume that no error occurred during the transmission of D. When D reaches B, which of the following IP header field(s) may be...

Consider the following three statements about link state and distance vector routing protocols, for a large network with 500 network nodes and 4000 links [S1] The computational overhead in link state protocols is higher...

Which one of the following is TRUE about the interior gateway routing protocols – Routing Information Protocol (RIP) and Open Shortest Path First (OSPF)?

An IP router with a Maximum Transmission Unit (MTU) of 1500 bytes has received an IP packet of size 4404 bytes with an IP header of length 20 bytes. The values of the relevant fields in the header of the third IP fragmen...

Every host in an IPv4 network has a 1-second resolution real-time clock with battery backup. Each host needs to generate up to 1000 unique identifiers per second. Assume that each host has a globally unique IPv4 address....

In an IPv4 datagram, the M bit is 0, the value of HLEN is 10, the value of total length is 400 and the fragment offset value is 300. The position of the datagram, the sequence numbers of the first and the last bytes of t...

In the IPv4 addressing format, the number of networks allowed under Class C addresses is

An Internet Service Provider (ISP) has the following chunk of CIDR-based IP addresses available with it: 245.248.128.0/20. The ISP wants to give half of this chunk of addresses to Organization A, and a quarter to Organiz...

Consider a source computer (S) transmitting a file of size 10 6 bits to a destination computer (D) over a network of two routers (R 1 and R 2 ) and three links (L 1 , L 2 , and L 3 ). L 1 connects S to R 1 ; L 2 connects...

One of the header fields in an IP datagram is the Time to Live (TTL) field. Which of the following statements best explains the need for this field?

If a class B network on the Internet has a subnet mask of 255.255.248.0, what is the maximum number of hosts per subnet?

A computer on a 10 Mbps network is regulated by a token bucket. The token bucket is filled at a rate of 2 Mbps. It is initially filled to capacity with 16 Megabits. What is the maximum duration for which the computer can...

The address of a class B host is to be split into subnets with a 6-bit subnet number. What is the maximum number of subnets and the maximum number of hosts in each subnet?

For which one of the following reasons does Internet Protocol (IP) use the time-to-live (TTL) field in the IP datagram header?

Two computers C1 and C2 are configured as follows. C1 has IP address 203.197.2.53 and netmask 255.255.128.0. C2 has IP address 203.197.75.201 and netmask 255.255.192.0. which one of the following statements is true?

An organization has a class B network and wishes to form subnets for 64 departments. The subnet mask would be

In a packet switching network, packets are routed from source to destination along a single path having two intermediate nodes. If the message size is 24 bytes and each packet contains a header of 3 bytes, then the optim...

A TCP message consisting of 2100 bytes is passed to IP for delivery across two networks. The first network can carry a maximum payload of 1200 bytes per frame and the second network can carry a maximum payload of 400 byt...

Which of the following assertions is FALSE about the Internet Protocol (IP)?

The subnet mask for a particular network is 255.255.31.0. Which of the following pairs of IP addresses could belong to this network?