ASSIGNING IP ADDRESSES

1. Chapter 2 ASSIGNING IP ADDRESSES

2. Chapter 2: ASSIGNING IP ADDRESSES CHAPTER OVERVIEW • Describe the structure of IP addresses and subnet masks. • Specify which computers on a network should use public addresses and which should use private addresses. • Calculate IP addresses and subnet masks for subnetted networks. • List the drawbacks of manual TCP/IP client configuration. • Understand how DHCP automatically configures TCP/IP clients.

3. Chapter 2: ASSIGNING IP ADDRESSES UNDERSTANDING IP ADDRESSING • A 32-bit binary value that is typically expressed as four 8-bit decimal numbers, separated by periods, as in 192.168.63.45.

4. Chapter 2: ASSIGNING IP ADDRESSES IP ADDRESS COMPONENTS • Network ID—Defines the IP address of the network that the host is on • Host ID—Defines the address of that host on the network

5. Chapter 2: ASSIGNING IP ADDRESSES NETWORK IDENTIFIERS

6. Chapter 2: ASSIGNING IP ADDRESSES HOST IDENTIFIERS • Each system on the same network must have a unique host identifier. • Two systems on two different networks can have the same host identifiers. • Duplicate host identifiers will disable at least one of the systems.

7. Chapter 2: ASSIGNING IP ADDRESSES UNDERSTANDING SUBNET MASKS • Defines which bits of the IP address refer to the network ID and which bits refer to the host ID. • A binary value of 1 determines that the bit in that location refers to the network ID. • A binary value of 0 determines that the bit in that location refers to the host ID.

8. Chapter 2: ASSIGNING IP ADDRESSES UNDERSTANDING IP ADDRESS CLASSES

9. Chapter 2: ASSIGNING IP ADDRESSES DETERMINING IP ADDRESSING REQUIREMENTS • Registered • Can be used on the Internet • Assigned by the Internet Assigned Numbers Authority (IANA) • Unregistered • Can only be used on private networks • Can use any compliant numbering scheme

10. Chapter 2: ASSIGNING IP ADDRESSES PUBLIC AND PRIVATE NETWORKS • Public network—The Internet • Requires connected systems to use registered IP address • Private network—Any network that is not part of the Internet • Can use any IP addressing scheme

11. Chapter 2: ASSIGNING IP ADDRESSES USING REGISTERED ADDRESSES

12. Chapter 2: ASSIGNING IP ADDRESSES USING UNREGISTERED ADDRESSES

13. Chapter 2: ASSIGNING IP ADDRESSES PLANNING IP ADDRESSES • Systems with connection to the Internet require a registered IP address. • Systems that connect to the Internet indirectly can use unregistered IP addresses and a system such as NAT or a proxy server to gain Internet access. • Each segment on the network requires a unique network address.

14. Chapter 2: ASSIGNING IP ADDRESSES OBTAINING NETWORK ADDRESSES • Network addresses are normally obtained from your ISP. • For a small number of systems, ask for a group of addresses on the same subnet. • For a large number of systems, obtain a network address with sufficient host IDs.

15. Chapter 2: ASSIGNING IP ADDRESSES SUBNETTING IP ADDRESSES • What is subnetting? • The process of creating individual network addresses out of a larger network address

16. Chapter 2: ASSIGNING IP ADDRESSES UNDERSTANDING SUBNETTING

17. Chapter 2: ASSIGNING IP ADDRESSES SUBNETTING BETWEEN BYTES • Uses a single octet to express both the network and node addresses • Results in a single decimal which reflects the network and node addresses

18. Chapter 2: ASSIGNING IP ADDRESSES CALCULATING IP ADDRESSES USING THE BINARY METHOD

19. Chapter 2: ASSIGNING IP ADDRESSES CONVERTING BINARIES AND DECIMALS

20. Chapter 2: ASSIGNING IP ADDRESSES CALCULATING A SUBNET MASK • The subnet mask value is determined by the subnetting process. • Subnet mask value can be expressed in dotted decimal or slash notation.

21. Chapter 2: ASSIGNING IP ADDRESSES CALCULATING IP ADDRESSES USING THE SUBTRACTION METHOD • Take the decimal value of the quad in the subnet mask that contains both subnet and host identifier bits and subtract it from 256. • Repeatedly increment that result by the remainder from the step above. The result of each addition forms a subnet address.

22. Chapter 2: ASSIGNING IP ADDRESSES DEPLOYING IP ADDRESSES • Manual configuration • Installation answer file • DHCP

23. Chapter 2: ASSIGNING IP ADDRESSES CONFIGURING IP ADDRESSES MANUALLY

24. Chapter 2: ASSIGNING IP ADDRESSES USING ANSWER FILES • Each system requires a separate answer file. • One-off can be used only during installation of the operating system. • Relatively complex file structure requires testing and verification.

25. Chapter 2: ASSIGNING IP ADDRESSES DEPLOYING IP ADDRESSES USING DHCP • Automates IP address deployment • Allows for simple reconfiguration of IP addressing schemes • Eliminates human error in address assignment • Generates very little network traffic and requires minimal administration after initial setup and configuration

26. Chapter 2: ASSIGNING IP ADDRESSES UNDERSTANDING DHCP ALLOCATION METHODS • Dynamic • Automatic • Manual

27. Chapter 2: ASSIGNING IP ADDRESSES INSTALLING AND CONFIGURING A DHCP SERVER

28. Chapter 2: ASSIGNING IP ADDRESSES DEPLOYING DHCP CLIENTS

29. Chapter 2: ASSIGNING IP ADDRESSES UNDERSTANDING DHCP CLIENT/SERVER COMMUNICATIONS

30. Chapter 2: ASSIGNING IP ADDRESSES PLANNING A DHCP DEPLOYMENT • DHCP packets are broadcasts and are not forwarded by routers. • DHCP Relay agents forward DHCP requests. • Relay agents allow a single DHCP server to service the entire internetwork.

31. Chapter 2: ASSIGNING IP ADDRESSES DEPLOYING MULTIPLE DHCP SERVERS • Provides fault tolerance. • Must not have duplicate scopes. • Microsoft recommends the 80:20 rule.

32. Chapter 2: ASSIGNING IP ADDRESSES CHAPTER SUMMARY • Every computer on a TCP/IP network must have a unique IP address. • You can create subnets using any network address by using some of the host identifier bits to create a subnet identifier. • You can configure the TCP/IP clients on your network manually, or you can use DHCP servers to automatically allocate IP addresses and other configuration parameters to your computers as needed.