Network Layer

--- IPv4 uses 32-bit addresses, providing approximately 4.3 billion (2^32) unique addresses. With the explosive growth of internet-connected devices (smartphones, IoT devices, etc.), this address space has been exhausted. IPv6 uses 128-bit addresses, provid...

--- Definition: ICMP stands for Internet Control Message Protocol. It is a network layer protocol that is responsible for providing hosts with information about network problems in a TCP/IP network. Key Points: - ICMP is part of the Internet layer (Network ...

NAT (Network Address Translation) is a networking technique in which a router or firewall modifies the IP address information in packet headers as traffic passes through it. It allows multiple devices on a private (local) network to share a single public IP...

- Network Class: Class C - Default Subnet Mask: 255.255.255.0 (/24) - Network bits: 24, Host bits: 8 - Required subnets: 3 - Example network (for illustration, standard assumption): 192.168.1.0 No specific IP address is given in the question, so a represent...

- IP address: 172.16.0.0 - Required number of subnets: 2 First octet = 172, which lies in the range 128 to 191, so this is a Class B address. - Default subnet mask = 255.255.0.0 (/16) - Network bits = 16, Host bits = 16 To get 2 subnets, use $2^n \ge 2$: $$...

- Network: 192.168.3.0 - 192.168.3.255 (Class C, default mask /24 = 255.255.255.0) - Required subnets: 4 --- To create 4 subnets: $$2^n \geq 4 \implies 2^2 = 4 \implies n = 2 \text{ bits}$$ Borrow 2 bits from the host portion. --- Original: Borrow 2 host bi...

- Network: 150.10.0.0 to 150.10.255.255 - Network Address: 150.10.0.0 - Class B default mask: 255.255.0.0 (/16) - Host bits: 16 (last two octets) - Required subnets: 4 --- $$2^n \geq 4 \implies n = 2 \text{ bits}$$ Borrow 2 bits from the host portion (third...

- IP Address: $192.34.12.56/28$ - Prefix length: $/28$ (28 network bits) Only the last octet varies; first three octets remain $192.34.12$. --- $/28$ means 28 ones followed by 4 zeros: $$11111111.11111111.11111111.11110000 = 255.255.255.240$$ --- $$\text{Bl...

--- IPv4 is the fourth version of the Internet Protocol and is one of the core protocols of the Internet Protocol Suite. It is a connectionless protocol used for transmitting data packets across networks. - Address Size: IPv4 uses a 32-bit address, which al...

- IP address: 192.168.0.0 - Required number of subnets: 2 The first octet is 192, which lies in the range 192-223, so this is a Class C address. - Default subnet mask: $255.255.255.0$ (/24) - Network bits = 24, Host bits = 8 To create 2 subnets, use $2^n \g...

--- Classless Inter-Domain Routing (CIDR) is a method used by Internet Service Providers (ISPs) to allocate IP addresses in variable-sized blocks, without being restricted to the traditional Class A, B, or C boundaries. It replaces the old classful addressi...

--- Classful addressing is a method of organizing and allocating IPv4 addresses in which the 32-bit address space is divided into five fixed classes: A, B, C, D, and E. Each class occupies a specific portion of the address space, and the class of an address...

Distance Vector Routing: Each router maintains a table (vector) of minimum distances to every destination and shares this table only with its directly connected neighbors. It uses the Bellman-Ford algorithm to compute shortest paths. Link State Routing: Eac...

Distance Vector Routing is a dynamic routing algorithm where each router maintains a routing table (distance vector) that contains: - The destination network/node - The distance (cost/hop count) to reach that destination - The direction (vector) i.e., the n...

Link state routing is a dynamic routing algorithm where each router has complete knowledge of the entire network topology. Every router independently computes the shortest path to every other router using Dijkstra's Algorithm. It is used by protocols such a...

A routing table is a data structure stored in a router (or networked device) that lists the routes to particular network destinations. Routers use this table to make decisions on how to forward data packets based on their IP addresses. The routing table con...

A routing table is a data structure stored in a router (or networked device) that lists the routes to particular network destinations. It contains information such as destination network addresses, next-hop addresses, and interface information that a router...

Routing is the process of selecting a path for traffic in a network, directing packet forwarding on the basis of routing tables that maintain records of routes to various network destinations. --- As stated in the notes, unicast is the simplest form of rout...

--- IPv6 is the most recent version of the Internet Protocol (IP), developed to replace IPv4 due to the exhaustion of IPv4 address space. Feature Description ------ Address Size 128-bit address (compared to 32-bit in IPv4) Address Format Written in hexadeci...

IPv6 (Internet Protocol version 6) was developed to overcome the address exhaustion problem of IPv4. Its structure is as follows: - IPv6 addresses are 128 bits long (compared to 32 bits in IPv4). - They are written in hexadecimal colon notation (also called...