1. 70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network, Enhanced Chapter 4: Planning and Configuring Routing and Switching

2. Objectives Build IP networks Configure Windows Server 2003 as a router
Create and configure demand-dial connections
Understand the purpose of virtual LANs
Implement Network Address Translation
Work with Internet Connection Sharing
Configure Internet Connection Firewall
Plan Internet connectivity
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

3. Building a Subnetted IP Network
Subnetting: breaking a single large IP network into smaller networks
Main benefit of subnetting is network traffic control
Supernetting is the opposite process of subnetting
Supernetting combines multiple small networks into one large network
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

4. Binary Numbering and TCP/IP
IP addresses are expressed in dotted decimal notation
A computer looks at an IP address as a single group of 32 binary digits
The subnet mask determines which bits are part of the network ID and which bits are part of the host ID
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

5. Decimal Numbering
The decimal system uses the values from 0 to 9 for each digit
The value of the first column in the decimal numbering system is ten to the zero power (100=1); the value of the second column is ten to the first power (101=10) etc.
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

6. Binary Numbering Subnetting is based on binary
Binary is a base-two numbering system, which means that there are only two potential values for each digit, 0 and 1
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

7. Conversion Between Binary and Decimal
To convert a binary octet to a decimal value, multiply the digit in each column by the value of each column and then determine the sum of those products
Binary digits are always either 1 or 0, so multiply the value of each column by 1 or 0
Most people use Windows Calculator to perform the conversion
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

8. Activity 4-1: Converting Binary Numbers to Decimal Using Windows Calculator
The purpose of this activity is to convert numbers between binary and decimal numbering systems
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

9. Binary Subnet Masks
The binary process used by your computer to find the network ID is called ANDing
If both binary digits being compared have a value of 1, then the result is 1
If one digit is 0 and the other is 1, or if both digits are zero, then the result is 0
When an IP address is ANDed with a subnet mask, the result is the network ID
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

10. Activity 4-2: ANDing
The purpose of this activity is to find the network ID of several IP addresses based on the given subnet mask
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

11. The Benefits of Subnets
Subnetting provides the following benefits:
Improves performance
Reduces collisions
Limits broadcasts
Controls traffic
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

12. Reducing Collisions
Subnetting reduces the number of hosts on each network, reduces the amount of traffic on the network and improves throughput
In a routed network, each network is a separate collision domain
Collisions that occur on one network do not affect another network
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

13. Limiting Broadcasts
Subnetting a network creates multiple networks with fewer hosts on each network
The presence of fewer hosts on each network results in fewer broadcast messages, which reduces the processing load on each host
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

14. Controlling Traffic
Routers provides greater control over network traffic
Routers can implement rules about which packets they forward
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

15. Subnetting a Network
To subnet a network, you take some bits from the host ID and give them to the network ID
The number of subnets can be calculated using the formula 2n-2
In this formula, n is the number of bits taken from the host ID and used for subnetting
The minus 2 is only used for traditional subnetting in which the subnets of all 1s and all 0s are removed
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

16. Activity 4-3: Complex Subnetting
The purpose of this activity is to subnet a single large network into 10 smaller networks
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

17. Subnet Hosts
The formula 2n-2, is also used to calculate the number of usable hosts on a subnet
The formula finds the total number of combinations that can be created from n bits
However, when used to calculate the number of usable hosts on a subnet, n is the number of bits in the host ID, and two combinations are removed for the broadcast on the subnet and the subnet itself
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

18. Activity 4-4: Finding Valid Hosts
The purpose of this activity is to calculate the number of valid hosts on a subnet
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

19. Supernetting
Supernetting is used to create one large network from several smaller ones
Supernetting takes bits from the network ID and gives them to the host ID
All of the networks being combined for supernetting must be contiguous
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

20. Router Installation and Configuration
Main benefit of implementing Windows Server 2003 as a router within a small or midsized organization is cost
Routing is part of Routing and Remote Access Service (RRAS) and can be configured using the same wizard that is used to configure dial-up and VPN servers
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

21. Router Installation and Configuration (continued)
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

22. Activity 4-5: Configuring RRAS as a Router
The purpose of this activity is to configure Windows Server 2003 as a router
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

23. Routing Tables
The routing table is a list of the networks that are known to the router
Each entry in an IP routing table contains:
the IP address of the network
the subnet mask of the network
the gateway that is used to reach the network
the router interface that is used to reach the gateway
the metric that measures how far away the network is
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

24. Routing Tables (continued)
Static routing is the process by which routing tables are maintained manually by an administrator
Dynamic routing is the process by which routing tables are automatically generated by routers based on communication with other routers
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

25. Routing Protocols
Routing protocols are responsible for calculating the best path from one network to another and advertising routes for dynamic routing
The two routing protocols used in Windows Server 2003 for IP routing are:
Routing Information Protocol (RIP)
Open Shortest Path First (OSPF)
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

26. RIP
In Routing Information Protocol (RIP), the distance between networks is measured by the number of routers through which the data must pass, or hops
RIP is the simpler and more popular of the two protocols
The best path from one network to another is the path with the least number of hops
This is known as distance-vector routing
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

27. Activity 4-6: Installing and Using RIP
The purpose of this activity is to configure your server as an RIP router
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

28. OSPF
Open Shortest Path First (OSPF) is a routing algorithm that determines the best path from one network to another based on a configurable value called cost
OSPF is more flexible than RIP and better suited to complex routing environments
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

29. Configuring RIP In RIP you can configure:
The type of events to be logged
From which IP addresses this router accepts updates
Settings for each interface
How often routing table announcements are sent
How long entries in the routing table last before they expire
Many other options
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

30. Demand-Dial Connections
A demand-dial connection establishes a connection between two routers only when there is data to send
When a router with a demand-dial interface receives packets destined for a remote network, a connection is created so the packets can be sent
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

31. Creating Demand-Dial Connections
For a demand-dial connection to function properly you must:
Enable the server to perform demand-dial routing
Configure a port to allow demand-dial routing
Create a demand-dial interface
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

32. Demand-Dial Interface Wizard
New demand-dial connections are created using the Demand-Dial Interface Wizard
To start this wizard in the Routing and Remote Access snap-in, right-click Network Interfaces, and click New Demand-dial Interface
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

33. Activity 4-7: Creating a Demand-Dial Connection
The purpose of this activity is to create a demand-dial VPN connection
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

34. Demand-dial Interface Properties
Properties of the demand-dial interface can be used to configure security settings and the idle timeout
The idle timeout is on the Options tab
If the Connection type chosen is the Persistent connection option, then the servers are connected whenever RRAS is functional
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

35. Dial-out Hours/Demand-Dial Filters
A demand-dial connection can be configured with a set of dial-out hours that control when it can be active
Controls unwanted dial-up connections that might result in large long-distance charges
Demand-dial filters control which types of network traffic trigger a demand-dial connection
Reduces the number of connections activated and the amount of long-distance charges
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

36. Activity 4-8: Configuring Demand-Dial Filters
The purpose of this activity is to configure demand-dial filters to control the activation of demand-dial connections
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

37. Virtual LANs
A VLAN is a broadcast domain created by a switch based on:
Subnets
Protocols
MAC addresses
switch ports
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

38. Network Address Translation
NAT is a protocol used by routers to allow multiple clients to share a single Internet-addressable IP address
IP headers are modified to make the packet look as though it came from the NAT router
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

39. How NAT Works
NAT modifies the IP headers of packets that are forwarded through a router
When a packet is forwarded through the router, NAT removes the original source IP address and source port number
The source IP address changes to the IP address of the router
The source port number is changed to a randomly generated port number
To keep track of the translations that are being performed, NAT builds a table
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

40. How NAT Works (continued)
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

41. How NAT Works
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

42. Installing NAT
NAT is automatically installed when RRAS is configured to be a router, but interfaces must be added
The NAT/Basic Firewall tab allows you to configure whether this interface is a private interface, public interface, or basic firewall
For proper NAT functionality, one interface must be configured as public and one as private
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

43. Activity 4-9: Installing and Testing NAT
The purpose of this activity is to Install NAT and confirm it is functioning using a Web page on your instructor’s computer
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

44. Configuring NAT
The NAT protocol is configured by right-clicking NAT/Basic Firewall, and clicking Properties
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

45. Internet Connection Sharing
Internet Connection Sharing (ICS) is a Windows Server 2003 service that provides an automated way for a small office using Windows Server 2003 as a router to connect to the Internet
ICS automatically performs NAT and configures network connections
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

46. Internet Connection Firewall
Internet Connection Firewall (ICF) is a stateful packet filter (a filter that automatically creates reverse rules for response traffic) that can be used to protect any server running Windows Server 2003
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

47. Enabling ICF ICF is configured per connection
ICF is enabled in the properties of a connection
If ICF is enabled on a server that is not a router, only that server is protected
If ICF is enabled on a router, then all computers on the internal network are protected
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

48. Configuring ICF
To allow requests from the network to access services on the server running ICF, you need to configure services
The Security Logging tab, is used to configure:
the type of information that is logged
the location of the log
the maximum size of the log
ICF is capable of logging both dropped packets and successful connections
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

49. Activity 4-10: Installing ICF
The purpose of this activity is to install and configure ICF on your server
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

50. Planning Internet Connectivity
When planning Internet Connectivity a decision must be made on whether to use internal private addresses or Internet accessible IP addresses
Using Internet accessible IP addresses is more expensive
Using internal private IP addresses is more secure
Most organizations use internal private IP addresses
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

51. Summary
Subnetting is used to divide a single large network into multiple smaller networks
Supernetting is used to combine multiple smaller networks into one large network
The formula 2n-2 is used to calculate the number of subnets that can be created from n bits
RIP is a distance-vector routing algorithm that calculates paths based on hops
OSPF is a link-state routing algorithm that calculates paths based on a configurable metric called cost
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network

52. Summary (continued)
Demand-dial connections are activated only when network traffic requires them
NAT allows many computers to access the Internet using a single Internet-addressable IP address
ICS is an automated way to configure a router for NAT
ICF is a stateful packet filter
When planning Internet Connectivity a decision must be made on whether to use internal private addresses or Internet accessible IP addresses
70-293: MCSE Guide to Planning a Microsoft Windows Server 2003 Network