Ip addressing 1

IP AddressingIP Addressing

IP AddressingIP Addressing

Table 3-2: Binary to decimal conversion

MAC to IP Address TranslationMAC to IP Address Translation

• The MAC address identifies a specific computer on a network, so each MAC address is unique

• However, MAC address are not grouped logically, they cannot be modified, and they don’t give information about physical or logical network configuration

• Therefore, another addressing scheme called IP addressing was devised for use on large networks

IP ClassesIP Classes

• The Internet Assigned Numbers Authority (IANA) devised the hierarchical IP addressing structure

• The American Registry of Internet Numbers (ARIN) assigns IP addresses to public, private, and government organizations

• Five different groups of IP addresses (labeled Class A through E) exist on the Internet– Classes A, B, and C are assigned to governments, companies,

schools, and public entities for use on the Internet– Classes D and E are reserved for multicasting and

experimentation

TCP/IP Addressing TCP/IP Addressing

• TCP/IP uses 32 bits, or four numbers between 0 and 255, to address a computer.

• Each computer must have an IP address before it can connect to the Internet.

• Each IP packet must have an address before it can be sent to another computer.

• e.g. IP address: 222 . 62 . 17 . 23This might be the same IP address:  www.jln123.com

Class AClass A

• It seems 127.0.0.1 (decimal) is the highest assignable Class A address, but that particular address range is reserved for the loopback address

Figure 3-12: Class A addresses

Class BClass BClass CClass C

Figure 3-13: Class B addresses

Figure 3-14: Class C addresses

Class DClass D

• Class D addresses (also known as multicast addresses) are reserved for multicasting

Figure 3-15: Class D addresses

Class EClass EPrivate IP RangesPrivate IP Ranges

Figure 3-16: Class E addresses

Table 3-3: The private IP ranges

Subnet AddressingSubnet Addressing

• Subnet mask– Indicates how much of the IP address represents

the network or subnetwork– Standard (default) subnet masks are as follows:

• 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

Subnet MaskingSubnet Masking

Figure 3-21: Subnet mask values

Understanding Packet Transmission:Understanding Packet Transmission:Network to NetworkNetwork to Network

Figure 3-27: Router

Chapter SummaryChapter Summary

• TCP/IP is an entire suite of protocols that provides data transportation, management, and diagnostic capabilities for networks that use it

• TCP/IP maps to a four-layer network model:– Application– Transport– Internetwork– Network Interface

• TCP and UDP protocols reside at the Transport layer

• IP resides at the Internetwork layer

Chapter SummaryChapter Summary

• The IANA, InterNIC, and ARIN work together to subdivide and issue addresses for Internet clients

• You can subdivide addresses assigned by InterNIC