IPv4 and IPv6 Addressing PDF

IPv4 and IPv6 Addressing Syeda Tanzeela Lec 17  Introduction IP addressing is a crucial component of computer networking that enables devices to identify and communicate with each other on a network. The two main versions of IP addressing are IPv4 (Internet...

IPv4 and IPv6 Addressing Syeda Tanzeela Lec 17  Introduction IP addressing is a crucial component of computer networking that enables devices to identify and communicate with each other on a network. The two main versions of IP addressing are IPv4 (Internet Protocol version 4) IPv6 (Internet Protocol version 6)  IPv4 Addressing IPv4 is the fourth version of the Internet Protocol (IP) and has been the dominant addressing scheme used on the internet since its inception. It was developed in the 1980s to provide a unique identifier for each device on a network. An IPv4 address is a 32-bit number, which is written in dotted decimal notation as four octets (8-bit groups), separated by periods. Example IPv4 address: 192.168.0.1 Structure of IPv4 Address 32 bits = 4 octets (each octet is 8 bits). Each octet is represented by a decimal number ranging from 0 to 255. The address is divided into two parts: Network and Host. General format: Network Portion | Host Portion  IPv4 Address Classes IPv4 addresses are divided into five classes that differ based on the size of the network and the number of possible hosts. Class A (1.0.0.0 to 127.255.255.255): Supports 16 million hosts per network. – Network Bits: 8, Host Bits: 24 Class B (128.0.0.0 to 191.255.255.255): Supports 65,000 hosts per network. – Network Bits: 16, Host Bits: 16 Class C (192.0.0.0 to 223.255.255.255): Supports 254 hosts per network. – Network Bits: 24, Host Bits: 8 Class D (224.0.0.0 to 239.255.255.255): Reserved for multicast groups. Class E (240.0.0.0 to 255.255.255.255): Reserved for experimental purposes.  Private and Public IPv4 Addresses Private Addresses: These addresses are reserved for internal networks and are not routed on the internet. Common ranges include: – 10.0.0.0 – 10.255.255.255 – 172.16.0.0 – 172.31.255.255 – 192.168.0.0 – 192.168.255.255 Public Addresses: These addresses are assigned to devices directly connected to the internet.  Subnetting in IPv4 Subnetting allows a network to be divided into smaller, more efficient subnetworks. It involves borrowing bits from the host portion of the address to create multiple subnets. A subnet mask (e.g., 255.255.255.0) defines the boundary between the network and host portions of the address.  Example of Subnetting IP: 192.168.1.0 Subnet Mask: 255.255.255.0 Result: Subnet with 256 addresses (0-255), where 192.168.1.0 is the network address, and 192.168.1.255 is the broadcast address. IPv4 Address Exhaustion With only 32 bits, IPv4 can support around 4.3 billion unique addresses, which is insufficient due to the rapid growth of internet-connected devices. This has led to IPv4 address depletion, prompting the development of IPv6.  IPv6 Addressing IPv6 is the next generation of IP addressing, designed to address the limitations of IPv4. IPv6 uses 128-bit addresses, providing a significantly larger address space than IPv4. Example IPv6 address: 2001:0db8:85a3:0000:0000:8a2e:03 70:7334  Structure of IPv6 Address 128 bits = 8 blocks of 16 bits (written in hexadecimal). Each block is separated by colons (:). Each block represents a 16-bit number in hexadecimal format, ranging from 0000 to FFFF. General format: xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxx x Where x is a hexadecimal digit.  Key Features of IPv6 Larger Address Space: IPv6 offers a total of 2^128 (approximately 340 undecillion) possible addresses, which is more than enough to accommodate future growth. Simplified Header: IPv6 headers are simpler and more efficient for routers to process than IPv4. Improved Security: IPv6 was designed with security in mind, incorporating features like IPsec (Internet Protocol Security) to ensure encryption and integrity of data.  IPv6 Address Types Unicast: Identifies a single sender and a single receiver. Multicast: Identifies a group of receivers, allowing a message to be sent to multiple destinations. Anycast: A one-to-nearest communication method, where data is sent to the closest of multiple possible destinations.  IPv6 Address Types by Prefix Global Unicast Address (GUA): Globally unique, publicly routable addresses (similar to public IPv4 addresses). The format is 2000::/3. Link-local Address: Used for communication within a local network segment. The format is fe80::/10. Unique Local Address (ULA): Private addresses for local networks, similar to IPv4 private addresses. The format is fc00::/7.  IPv6 Notation and Abbreviations Compression of Zeroes: Leading zeros in each block can be omitted, and consecutive blocks of zeroes can be replaced with :: (but only once per address). – Example: 2001:0db8:0000:0000:0000:0000:0000:0020 becomes 2001:db8::20 IPv6 Prefix Length: Similar to subnet masks in IPv4, IPv6 uses a prefix length (e.g., /64) to denote the size of the network portion.  IPv4 vs. IPv6 Feature IPv4 IPv6 Address Length 32 bits 128 bits Decimal (e.g., Hexadecimal (e.g., Address Format 192.168.0.1) 2001:0db8::1) 340 undecillion Address Space ~4.3 billion addresses addresses Complex, with options Header Complexity Simpler, no checksum and checksum Mandatory IPsec Security Optional (IPsec) support Stateless Configuration Manual or DHCP Autoconfiguration No broadcast, uses Broadcast Support Supports broadcast multicast More complex due to More efficient, simpler Routing NAT and address routing  Transition from IPv4 to IPv6 Dual Stack: Many devices and networks run both IPv4 and IPv6 simultaneously. Tunneling: IPv6 packets are encapsulated within IPv4 packets for transmission. Translation: IPv4 and IPv6 addresses can be translated using protocols like NAT64.  Addressing Use Cases Internet Devices: IPv4 continues to be widely used in existing networks and devices. It’s the most common protocol for most internet communication today. Private Networks: Often used in internal corporate networks. 4.2 IPv6 Use Case Next-generation Internet: IPv6 is essential for supporting the growing number of devices connected to the internet, such as IoT devices. Mobile Networks: IPv6 is better suited for mobile networks due to its efficient address allocation and autoconfiguration features.  Conclusion IPv4 and IPv6 are essential technologies for modern networking, each addressing different needs. While IPv4 has been the standard for decades, IPv6 is the future- proof solution to address the limitations of IPv4, particularly the depletion of available addresses. As the number of connected devices grows, IPv6 will become increasingly important to ensure the continued growth and scalability of the internet.