IP Addresses, or Internet Protocol Addresses, are unique numerical identifiers assigned to devices connected to a network. They play a crucial role in network communication, allowing devices to send and receive data across the Internet or other interconnected networks.
Here are some key points about IP addresses:
IP addresses are typically represented in either IPv4 or IPv6 format.
IPv4: IPv4 addresses are 32-bit numbers written in decimal format, divided into four octets separated by periods (e.g., 192.168.0.1).
IPv6: IPv6 addresses are 128-bit numbers written in hexadecimal format, divided into eight groups of four hexadecimal digits separated by colons (e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334).
IPv4 IPv6 Address Format 32-bit decimal format (e.g., 192.168.0.1) 128-bit hexadecimal format (e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334) Address Space Limited address space (4.3 billion addresses) Vast address space (approximately 3.4×10^38 addresses) Address Representation Dotted decimal notation Hexadecimal notation Address Configuration Manual configuration or DHCP Autoconfiguration, stateless or stateful DHCPv6 Address Types Public and private addresses Global unicast, unique local, link-local, multicast Address Resolution ARP (Address Resolution Protocol) Neighbor Discovery Protocol (NDP) Header Format Fixed-length header (20 bytes) Fixed-length base header (40 bytes) with optional extension headers Fragmentation Routers perform fragmentation Fragmentation is handled by the source device Security Limited built-in security features Improved security features and IPsec integration Quality of Service (QoS) Limited support for QoS Enhanced support for QoS and flow labeling Mobility Requires additional protocols (e.g., Mobile IP) Built-in support for mobility through Mobile IPv6 Migration Coexistence with IPv6 through transition mechanisms (e.g., dual-stack, tunneling) Transition mechanisms to facilitate the migration from IPv4 to IPv6
Public IP Address Private IP Address Accessibility Routable on the public Internet Not routable on the public Internet Unique Globally unique address Not globally unique, can be reused in different private networks Assigning Authority Assigned by Internet Service Providers (ISPs) or network administrators Assigned by network administrators within private networks Internet Visibility Can be directly accessed from the Internet Not directly accessible from the Internet NAT Translation Not typically subjected to Network Address Translation (NAT) Often subjected to NAT when accessing the Internet Address Range Reserved ranges allocated by Internet Assigned Numbers Authority (IANA) Ranges specified for private use (e.g., 10.0.0.0 – 10.255.255.255, 192.168.0.0 – 192.168.255.255) Usage Assigned to devices that require direct Internet connectivity (e.g., servers, routers) Used within private networks for local communication (e.g., home or office networks) Security May require additional security measures to protect against unauthorized access Offers some level of inherent security by limiting direct exposure to the Internet Scalability Limited address space, potential for address exhaustion Larger address space, accommodating more devices within private networks Public Services Can host public-facing services accessible over the Internet Typically used for internal services and communication within the private network
DHCP Static IP Address Assignment Dynamic assignment of IP addresses by a DHCP server Manual assignment of IP addresses to devices Configuration Ease Automates IP address configuration Requires manual configuration on each device IP Address Management Centralized management by DHCP server Individual IP address management for each device Address Renewal IP addresses are leased for a specific time period and can be renewed IP addresses remain the same until manually changed Flexibility Allows for easy reconfiguration and reallocation of IP addresses IP addresses are fixed and do not change over time Scalability Suitable for networks with a large number of devices Suitable for networks with a small number of devices Administration Simplifies administration by automating IP address assignments Requires manual tracking and documentation of IP addresses Network Changes Automatically adjusts IP addresses in response to network changes Requires manual reconfiguration when network changes occur Network Complexity Well-suited for dynamic network environments with frequent device additions and removals Suitable for static network environments with minimal changes Troubleshooting Simplifies troubleshooting as IP addresses are dynamically assigned Requires manual verification and troubleshooting of static IP configurations IP Address Conflict Less susceptible to IP address conflicts due to dynamic assignment Possible conflicts if static IP addresses are assigned incorrectly or duplicated
Subnetting Subnet Masks Definition Dividing a network into smaller subnetworks A binary pattern used to determine the network and host portions of an IP address Purpose Efficient utilization of IP address space, network segmentation, and better network management Identifying the network and host portions of an IP address within a subnet Result Creation of multiple smaller subnetworks within a larger network Division of an IP address into network and host portions Address Allocation Allocating IP address ranges to subnets Assigning subnet masks to devices or subnets Address Range Determining the range of IP addresses available within each subnet N/A Subnet Identification Assigning a unique subnet ID to each subnet N/A Addressing Flexibility Provides flexibility in allocating IP addresses to different subnets Determines the size of the network and host portions within a subnet Routing Facilitates routing between different subnets Used by routers to determine the network portion for routing decisions Communication Devices within the same subnet can communicate directly without routing Communication between different subnets requires routing Network Segmentation Enables logical separation of networks for security, performance, and management purposes N/A Subnet Mask Format Expressed in decimal format (e.g., 255.255.255.0) or CIDR notation (e.g., /24) N/A Subnet Mask Usage Applied to IP addresses using a bitwise AND operation to determine the network and host portions N/A
