Chapter 11: Networking with TCP/IP and the Internet

Objectives

Discuss methods of network design unique to TCP/IP networks, including subnetting, CIDR, and NAT

Describe protocols used between mail clients and mail servers

Objectives (continued)

Explain the fundamental principles of using a TCP/IP network for packetized voice transmissions

Employ multiple TCP/IP utilities for network discovery and troubleshooting

Designing TCP/IP-Based Networks

• Subnetting• Enhance security

• Improve performance

• Simplify troubleshooting

Designing TCP/IP-Based Networks (continued)

• Subnetting• Classful Addressing

Designing TCP/IP-Based Networks (continued)

Designing TCP/IP-Based Networks (continued)

• Subnetting• Subnet Masks

Designing TCP/IP-Based Networks (continued)

Designing TCP/IP-Based Networks (continued)

Designing TCP/IP-Based Networks (continued)

Designing TCP/IP-Based Networks (continued)

• Subnetting• Reserved Addresses

Designing TCP/IP-Based Networks (continued)

• Subnetting• Subnetting Techniques

Designing TCP/IP-Based Networks (continued)

Designing TCP/IP-Based Networks (continued)

Designing TCP/IP-Based Networks (continued)

• Subnetting• Calculating Subnets

Designing TCP/IP-Based Networks (continued)

Designing TCP/IP-Based Networks (continued)

• Subnetting • Classless Inter-Domain Routing (CIDR)

• Classless routing or supernetting

Designing TCP/IP-Based Networks (continued)

Designing TCP/IP-Based Networks (continued)

Designing TCP/IP-Based Networks (continued)

Designing TCP/IP-Based Networks (continued)

• Subnetting • Internet Gateways

Designing TCP/IP-Based Networks (continued)

This host will not get outside its network, Why? Assume a /24 mask.

Designing TCP/IP-Based Networks (continued)

• Subnetting • Network Address Translation (NAT)

Designing TCP/IP-Based Networks (continued)

Designing TCP/IP-Based Networks (continued)

• Subnetting• Intranets and Extranets

• Hypertext Markup Language (HTML)

• Intranet

• Within an enterprise

• Extranet

• Uses Internet-like services and protocols

Designing TCP/IP-Based Networks (continued)

• Simple Mail Transfer Protocol (SMTP)• Protocol responsible for moving messages from

one mail server to another over TCP/IP-based networks

TCP/IP Mail Services

• MIME (Multipurpose Internet Mail Extensions)• Allows for messages that contain no more than

1000 ASCII characters

TCP/IP Mail Services (continued)

• Post Office Protocol (POP)• Application layer protocol used to retrieve

messages from a mail server

TCP/IP Mail Services (continued)

• Internet Mail Access Protocol (IMAP)• Retrieve all or only a portion of any mail message

• Review their messages and delete them while the messages remain on the server

• Create sophisticated methods of organizing messages on the server

• Share a mailbox in a central location

Additional TCP/IP Utilities

• Netstat• -a—Provides a list of all available TCP and UDP

connections

• -e—Displays details about all the packets

• -n—Lists currently connected hosts according to their port and IP address

Additional TCP/IP Utilities (continued)

• Netstat (cont.)• -p—Allows you to specify what type of protocol

statistics to list

• Must be followed by a protocol specification (TCP or UDP)

• -r—Provides a list of routing table information

• -s—Provides statistics about each packet transmitted by a host, separated according to protocol type (IP,TCP, UDP, or ICMP)

Additional TCP/IP Utilities (continued)

Additional TCP/IP Utilities (continued)

• Nbtstat• -a—Displays a machine’s name table given its

NetBIOS name

• -A—Displays a machine’s name table given its IP address

• -r—Lists statistics about names that have been resolved

• -s—Displays a list of all the current NetBIOS sessions

Additional TCP/IP Utilities (continued)

• Nslookup• Allows you to query the DNS database

Additional TCP/IP Utilities (continued)

Additional TCP/IP Utilities (continued)

• Whois• Allows you to query this DNS registration

database and obtain information about a domain

Additional TCP/IP Utilities (continued)

• Traceroute (Tracert)• -d—Instructs the traceroute command not to

resolve IP addresses to host names

• -h—Specifies the maximum number of hops

• -w—Identifies a timeout

Additional TCP/IP Utilities (continued)

Additional TCP/IP Utilities (continued)

• Ipconfig• /?—Displays a list of switches

• /all—Displays complete TCP/IP configuration

• /release—Releases DHCP

• /renew—Renews DHCP

• /displaydns---Displays DNS Cache

• /flushdns---Clears DNS Cache (not host file)

Additional TCP/IP Utilities (continued)

Additional TCP/IP Utilities (continued)

• Winipcfg• Windows 9x and Me operating systems

Additional TCP/IP Utilities (continued)

Additional TCP/IP Utilities (continued)

• Ifconfig• -a

• down

• up

Additional TCP/IP Utilities (continued)

Voice Over IP (VOIP)

• Voice over IP (VoIP), also known as IP telephony• Lower costs for voice calls

• toll bypass

• Supply new or enhanced features and applications

• Centralize voice and data network management

Voice Over IP (VOIP) (continued)

Voice Over IP (VOIP) (continued)

Voice Over IP (VOIP) (continued)

Chapter Summary

• Discuss methods of network design unique to TCP/IP networks, including subnetting, CIDR, and NAT

• Describe protocols used between mail clients and mail servers

Chapter Summary (continued)

• Explain the fundamental principles of using a TCP/IP network for packetized voice transmissions

• Employ multiple TCP/IP utilities for network discovery and troubleshooting