11 NETWORK PROTOCOLS AND SERVICES Chapter 10

Chapter 10: Network Protocols and Services2 NETWORK PROTOCOLS AND SERVICES  Identify how computers on TCP/IP networks communicate  Explain how IP addresses and subnetting work  Explain how name resolution works, and identify the primary name resolution mechanisms that are used on Microsoft Windows networks  Identify how computers on TCP/IP networks communicate  Explain how IP addresses and subnetting work  Explain how name resolution works, and identify the primary name resolution mechanisms that are used on Microsoft Windows networks

Chapter 10: Network Protocols and Services3 NETWORK PROTOCOLS AND SERVICES (CONTINUED)  Troubleshoot networking problems caused by cable connections, network adapters, modems, TCP/IP configuration, or name resolution settings.  Configure and troubleshoot Internet Connection Firewall  Configure Remote Assistance and Remote Desktop  Troubleshoot networking problems caused by cable connections, network adapters, modems, TCP/IP configuration, or name resolution settings.  Configure and troubleshoot Internet Connection Firewall  Configure Remote Assistance and Remote Desktop

Chapter 10: Network Protocols and Services4 TCP/IP CONFIGURABLE OPTIONS  IP address (mandatory)  Subnet mask (mandatory)  Default gateway (optional)  DNS configuration (optional)  WINS configuration (optional)  IP address (mandatory)  Subnet mask (mandatory)  Default gateway (optional)  DNS configuration (optional)  WINS configuration (optional)

Chapter 10: Network Protocols and Services5 IP ADDRESS CLASSES  Class A addresses  Class B addresses  Class C addresses  Class D addresses  Class E addresses  Loopback addresses  Class A addresses  Class B addresses  Class C addresses  Class D addresses  Class E addresses  Loopback addresses

Chapter 10: Network Protocols and Services6 IP ADDRESS VALIDITY  The first byte of the IP address must fall within the following ranges:  1 through 126  128 through 191  192 through 223  IP addresses that begin with 0, 127, or 224 through 255 are invalid  The host ID cannot be all binary 0s or 1s  No number in an IP address can be greater than 255  The first byte of the IP address must fall within the following ranges:  1 through 126  128 through 191  192 through 223  IP addresses that begin with 0, 127, or 224 through 255 are invalid  The host ID cannot be all binary 0s or 1s  No number in an IP address can be greater than 255

Chapter 10: Network Protocols and Services7 CHOOSING AN IP ADDRESSING SCHEME  through  through  through  through  through  through

Chapter 10: Network Protocols and Services8 SUBNET MASKS  Class A:  Class B:  Class C:  Class A:  Class B:  Class C:

Chapter 10: Network Protocols and Services9 DEFAULT GATEWAY

Chapter 10: Network Protocols and Services10 DNS  Name resolution for TCP/IP clients  Service resolution  Resolve TCP/IP host names and FQDNs to IP addresses  Name resolution for TCP/IP clients  Service resolution  Resolve TCP/IP host names and FQDNs to IP addresses

Chapter 10: Network Protocols and Services11 TCP/IP HOSTS FILE

Chapter 10: Network Protocols and Services12 NetBIOS  NetBIOS Enhanced User Interface (NetBEUI) is a fast, efficient protocol, suitable for use on small networks.  Not used very much anymore  Will have to enable a WINS server or use the LMHOSTS file  NetBIOS Enhanced User Interface (NetBEUI) is a fast, efficient protocol, suitable for use on small networks.  Not used very much anymore  Will have to enable a WINS server or use the LMHOSTS file

Chapter 10: Network Protocols and Services13 WINS  In multiple-network environments, a WINS server can be used to maintain a database of NetBIOS name-to-IP address mappings, similar to a DNS server maintaining a database of host name-to-IP address mappings

Chapter 10: Network Protocols and Services14 LMHOSTS FILE  The Lmhosts file is a simple text file that contains IP addresses followed by the name of the host, similar to a TCP/IP hosts file. The Lmhosts file is stored in the System_root\System32\Drivers\Etc folder.

Chapter 10: Network Protocols and Services15 CONFIGURING LAN AND HIGH-SPEED INTERNET CONNECTIONS

Chapter 10: Network Protocols and Services16 ADDING A NETWORK COMPONENT

Chapter 10: Network Protocols and Services17 RENAMING, DISABLING, AND DELETING A LOCAL AREA CONNECTION

Chapter 10: Network Protocols and Services18 CONFIGURING TCP/IP

Chapter 10: Network Protocols and Services19 ALTERNATE TCP/IP CONFIGURATION BY USER- CONFIGURED SETTINGS

Chapter 10: Network Protocols and Services20 MANUAL CONFIGURATION OF TCP/IP PROPERTIES  Automatic configuration of TCP/IP properties is convenient, but there will be situations where you will want the control that is afforded by manual configuration

Chapter 10: Network Protocols and Services21 GENERAL NETWORK TROUBLESHOOTING  What isn’t working?  What is working?  Did whatever isn’t working ever work?  Does it work intermittently or not at all?  Has anything changed since the last time it worked?  Is there a relationship between things that are working and things that are not?  What isn’t working?  What is working?  Did whatever isn’t working ever work?  Does it work intermittently or not at all?  Has anything changed since the last time it worked?  Is there a relationship between things that are working and things that are not?

Chapter 10: Network Protocols and Services22 TROUBLESHOOTING TCP/IP  Are the computers involved physically connected to the network?  Does Event Viewer report any warnings or errors?  Are TCP/IP parameters configured correctly?  Is the computer receiving an address from the DHCP server?  Are the computers involved physically connected to the network?  Does Event Viewer report any warnings or errors?  Are TCP/IP parameters configured correctly?  Is the computer receiving an address from the DHCP server?

Chapter 10: Network Protocols and Services23 TROUBLESHOOTING TCP/IP (CONTINUED)  Can the computer establish basic connectivity using the Ping command?  Is there a DNS or NetBIOS name-resolution problem?  Are the default gateway and additional routes configured in the local routing table?  Can the computer establish basic connectivity using the Ping command?  Is there a DNS or NetBIOS name-resolution problem?  Are the default gateway and additional routes configured in the local routing table?

Chapter 10: Network Protocols and Services24 TROUBLESHOOTING PHYSICAL CONNECTIVITY  Check the properties of the network adapter  Make sure that the network cable is connected to the network card  Check the properties of the network adapter  Make sure that the network cable is connected to the network card

Chapter 10: Network Protocols and Services25 VERIFYING TCP/IP CONFIGURATION  TCP/IP settings to check include:  Incorrect IP address  Duplicate IP address  Incorrect subnet mask  Incorrect or missing default gateway  Incorrect or missing DNS server  Incorrect or missing WINS server  TCP/IP settings to check include:  Incorrect IP address  Duplicate IP address  Incorrect subnet mask  Incorrect or missing default gateway  Incorrect or missing DNS server  Incorrect or missing WINS server

Chapter 10: Network Protocols and Services26 PING

Chapter 10: Network Protocols and Services27 IPCONFIG

Chapter 10: Network Protocols and Services28 TROUBLESHOOTING DHCP CLIENTS  Use Ipconfig /renew to force the client to refresh the DHCP configuration  Ensure that the DHCP server is functioning and is not out of IP addresses  If the DHCP server is remote, verify that the DHCP Relay Agent is functioning  Use Ipconfig /renew to force the client to refresh the DHCP configuration  Ensure that the DHCP server is functioning and is not out of IP addresses  If the DHCP server is remote, verify that the DHCP Relay Agent is functioning

Chapter 10: Network Protocols and Services29 TROUBLESHOOTING BASIC CONNECTIVITY  If the client appears to have an appropriate TCP/IP configuration, you can perform basic connectivity testing using the Ping command

Chapter 10: Network Protocols and Services30 TRACERT COMMAND  The Tracert command-line utility can help you figure out exactly where along the route the breakdown happened

Chapter 10: Network Protocols and Services31 PATHPING COMMAND  The Pathping command is a combination of both Ping and Tracert, displaying information about packet loss at every router between the host computer and the remote one

Chapter 10: Network Protocols and Services32 TCP/IP HOST NAME RESOLUTION METHODS  Local host name  DNS cache  Hosts file  DNS server  Local host name  DNS cache  Hosts file  DNS server

Chapter 10: Network Protocols and Services33 NETBIOS NAME RESOLUTION METHODS  NetBIOS name cache  WINS server  Broadcast  Lmhosts file  NetBIOS name cache  WINS server  Broadcast  Lmhosts file

Chapter 10: Network Protocols and Services34 UNDERSTANDING INTERNET CONNECTION FIREWALL  Limits the data that comes into a computer or a network  Does not limit what happens on a stand- alone computer or inside the network, or the data that passes between computers on a local network  Works independently of any networking hardware  Can keep a security log of discarded packets  Limits the data that comes into a computer or a network  Does not limit what happens on a stand- alone computer or inside the network, or the data that passes between computers on a local network  Works independently of any networking hardware  Can keep a security log of discarded packets

Chapter 10: Network Protocols and Services35 ENABLING INTERNET CONNECTION FIREWALL

Chapter 10: Network Protocols and Services36 ICF LOGGING  Two available ICF logging options:  Log Dropped Packets  Log Successful Connections  Two available ICF logging options:  Log Dropped Packets  Log Successful Connections

Chapter 10: Network Protocols and Services37 INTERNET CONTROL MESSAGE PROTOCOL (ICMP)

Chapter 10: Network Protocols and Services38 ALLOWING SERVICES IN ICF

Chapter 10: Network Protocols and Services39 ESTABLISHING A REMOTE ASSISTANCE SESSION Start Menu – Help and Support

Chapter 10: Network Protocols and Services40 REMOTE ASSISTANCE CONSOLE

Chapter 10: Network Protocols and Services41 TAKING SHARED CONTROL OF THE USER’S COMPUTER  Can fully manipulate the computer  Can load and unload drivers  Can launch applications  Can View event logs  Cannot copy files from the user’s hard drive  Can fully manipulate the computer  Can load and unload drivers  Can launch applications  Can View event logs  Cannot copy files from the user’s hard drive

Chapter 10: Network Protocols and Services42 REMOTE DESKTOP  Remote Desktop is designed to allow a user to have full control over her or his Windows XP Professional Edition desktop from another computer on the network

Chapter 10: Network Protocols and Services43 CONFIGURING REMOTE DESKTOP Must have the check box selected. Port 3389 must be opened on the firewall.

Chapter 10: Network Protocols and Services44 MANAGING REMOTE DESKTOP SESSIONS

Chapter 10: Network Protocols and Services45 CHAPTER SUMMARY  When configuring TCP/IP, you must configure an IP address and a subnet mask. Optionally, you can configure a default gateway and name server addresses.  A computer can obtain IP addressing information automatically or you can configure a static IP address.  Name resolution is the process of resolving a user-friendly name to an IP address. Name resolution mechanisms include DNS and WINS.  When configuring TCP/IP, you must configure an IP address and a subnet mask. Optionally, you can configure a default gateway and name server addresses.  A computer can obtain IP addressing information automatically or you can configure a static IP address.  Name resolution is the process of resolving a user-friendly name to an IP address. Name resolution mechanisms include DNS and WINS.

Chapter 10: Network Protocols and Services46 CHAPTER SUMMARY (CONTINUED)  When troubleshooting a networking problem, you should check for problems with cable connections, network adapters, modems, TCP/IP configuration, or name resolution settings.  Internet Connection Firewall provides a level of security against unwanted network traffic coming from outside your private network.  When troubleshooting a networking problem, you should check for problems with cable connections, network adapters, modems, TCP/IP configuration, or name resolution settings.  Internet Connection Firewall provides a level of security against unwanted network traffic coming from outside your private network.

Chapter 10: Network Protocols and Services47 CHAPTER SUMMARY (CONTINUED)  Remote Assistance provides a way for a user to request help from an expert and even let that expert control the user’s desktop. Remote Desktop provides a way for a user to control his or her desktop while away from the main computer.