Basic Internetworking in Computer Networks
Logical addressing in computer networks refers to the methods and schemes used to assign unique identifiers (addresses) to devices and interfaces within a network. These logical addresses are used for communication and routing purposes, allowing devices to locate and communicate with one another across the network. Here's an overview of logical addressing in computer networks:
IP Addressing
IP (Internet Protocol) addressing is the primary logical addressing scheme used in modern computer networks, particularly the Internet and TCP/IP-based networks.
- IPv4 and IPv6 are the two versions of IP addressing currently in use.
- IPv4 addresses are 32-bit numbers represented in dotted-decimal notation (e.g., 192.168.0.1), while IPv6 addresses are 128-bit numbers represented in hexadecimal notation (e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334).
- IP addresses are hierarchical, with network and host portions, allowing for efficient routing and network segmentation.
Subnet Masking
Subnet masks are used in conjunction with IP addresses to divide a network into smaller subnetworks or subnets.
- Subnet masks define the boundary between the network and host portions of an IP address, enabling efficient use of available IP address space.
Network Address Translation (NAT)
NAT is a technique used to conserve IP addresses by allowing multiple devices within a private network to share a single public IP address.
- NAT translates private IP addresses to a public IP address for communication across networks and vice versa.
Port Addressing
Port numbers are used in conjunction with IP addresses to identify specific applications or services running on a host.
- Port numbers range from 0 to 65535, with well-known ports assigned to standard services (e.g., HTTP: 80, HTTPS: 443).
MAC Addressing
MAC (Media Access Control) addresses are used for physical addressing at the data link layer of the OSI model.
- MAC addresses are unique identifiers assigned to network interface cards (NICs) by manufacturers.
- MAC addresses are used for communication within a local area network (LAN) and are essential for Ethernet and other LAN technologies.
Hierarchical Addressing
Logical addressing schemes often follow a hierarchical structure, allowing for efficient routing and address management.
- For example, IP addresses are divided into network and host portions, with network addresses further subdivided into smaller subnets using subnet masks.
Logical addressing plays a crucial role in computer networks, enabling devices to communicate with one another, facilitating routing, and allowing for efficient use of available address space. It is an essential component of modern networking protocols and architectures.