OSI Model IP address

MAC to IP Address Comparison MAC address Identifies a NIC in a computer on a network Each MAC address is unique TCP/IP networks can use MAC addresses in communication Network devices cannot efficiently way traffic using MAC addresses because they: Are not grouped logically Cannot be changed Do not give information about physical or logical network configuration CCNA Guide to Cisco Networking Fundamentals, Fourth Edition

MAC to IP Address Comparison (continued) IP addressing Developed for use on large networks IP addresses have a hierarchical structure and do provide logical groupings IP address identifies both a network and a host CCNA Guide to Cisco Networking Fundamentals, Fourth Edition

OSI Model Versions of IP address IPv4 IPv6

OSI Model IPv4

Types of IP address Static address Dynamic address

Types of IP address Static IP address manually input by network administrator manageable for small networks requires careful checks to avoid duplication

Types of IP address Dynamic IP address Used protocol DHCP assigned by server when host boots derived automatically from a range of addresses duration of ‘lease’ negotiated, then address released back to server

IP Addressing An IP address has 32 bits divided into four octets To make the address easier to read, people use decimal numbers to represent the binary digits Example: 192.168.1.1 Dotted decimal notation When binary IP addresses are written in decimal format CCNA Guide to Cisco Networking Fundamentals, Fourth Edition

Conversion CCNA Guide to Cisco Networking Fundamentals, Fourth Edition

Binary and Decimal Conversion

Example 5.1 Change the following IPv4 addresses from binary notation to dotted-decimal notation. a. 10000001 00001011 00001011 11101111 b. 11000001 10000011 00011011 11111111 c. 11100111 11011011 10001011 01101111 d. 11111001 10011011 11111011 00001111 Solution We replace each group of 8 bits with its equivalent decimal number (see Appendix B) and add dots for separation: a. 129.11.11.239 b. 193.131.27.255 c. 231.219.139.111 d. 249.155.251.15 TCP/IP Protocol Suite

Example 5.2 Change the following IPv4 addresses from dotted-decimal notation to binary notation. a. 111.56.45.78 b. 221.34.7.82 c. 241.8.56.12 d. 75.45.34.78 Solution We replace each decimal number with its binary equivalent: a. 01101111 00111000 00101101 01001110 b. 11011101 00100010 00000111 01010010 c. 11110001 00001000 00111000 00001100 d. 01001011 00101101 00100010 01001110 TCP/IP Protocol Suite

Example 5.3 Find the error, if any, in the following IPv4 addresses: b. 221.34.7.8.20 c. 75.45.301.14 d. 11100010.23.14.67 Solution a. There should be no leading zeroes (045). b. We may not have more than 4 bytes in an IPv4 address. c. Each byte should be less than or equal to 255. d. A mixture of binary notation and dotted-decimal notation. TCP/IP Protocol Suite

IP Address as a 32-Bit Binary Number

Classes of IP address Class A - large organizations , governments Class B - medium sized organizations Class C - small organizations Class D- Multicasting is the sending of a stream of data (usually audio and video) to multiple computers simultaneously Class E Addresses are reserved for research, testing, and experimentation The Class E range starts where Class D leaves off

Classify and Define IPv4 Addresses Identify the historic method for assigning addresses and the issues associated with the method

IP Address Classes

IP Address Classes

IP Addresses as Decimal Numbers

IP Classes (continued) CCNA Guide to Cisco Networking Fundamentals, Fourth Edition

IP Classes (continued) CCNA Guide to Cisco Networking Fundamentals, Fourth Edition

IP Classes (continued) CCNA Guide to Cisco Networking Fundamentals, Fourth Edition

Network Addressing IP addresses identify both the network and the host Subnet mask Determines which part of an IP address is the network field and which part is the host field Standard (default) subnet masks: Class A subnet mask is 255.0.0.0 Class B subnet mask is 255.255.0.0 Class C subnet mask is 255.255.255.0 CCNA Guide to Cisco Networking Fundamentals, Fourth Edition

Default Subnet Masks

Subnetting TCP/IP hosts use the combination of the IP address and the subnet mask To determine if other addresses are local or remote The binary AND operation is used to perform the calculation Subnetting Manipulation of the subnet mask to get more network numbers CCNA Guide to Cisco Networking Fundamentals, Fourth Edition

CCNA Guide to Cisco Networking Fundamentals, Fourth Edition

Subnet Mask Follow these steps to determine the subnet mask: 1. Express the subnetwork IP address in binary form. 2. Replace the network and subnet portion of the address with all 1s. 3. Replace the host portion of the address with all 0s. 4. Convert the binary expression back to dotted- decimal notation.

Subnet Mask Subnet mask in decimal = 255.255.240.0

Performing the AND Function

IPv4 versus IPv6 IP version 6 (IPv6) has been defined and developed. IPv6 uses 128 bits rather than the 32 bits currently used in IPv4. IPv6 uses hexadecimal numbers to represent the 128 bits. IPv4

IPv4 versus IPv6 IP version 4 (IPv4) IP version 6 (IPv6) The version of IP currently installed on most systems today IP version 6 (IPv6) Originally designed to address the final running down of IPv4 addresses IPv6 can be subnetted CCNA Guide to Cisco Networking Fundamentals, Fourth Edition