User Guide

Page 178 SonicWALL Internet Security Appliance User’s Guide
Appendix B - Introduction to Networking
Overview
This appendix provides a non-technical overview of the network protocols supported by the
SonicWALL and includes a discussion of Internet Protocol (IP) addressing.
It can be helpful to review a book on TCP/IP for an overview of protocols such as TCP
(Transmission Control Protocol), UDP (User Datagram Protocol), and ICMP (Internet
Control Message Protocol). The following book is recommended for beginner and
intermediate network administrators:
Teach Yourself TCP/IP in 14 Days Second Edition
Timothy Parker, Ph.D
SAMS Publishing
ISBN # 0-672-30885-1
Network Hardware Components
• Computers - IBM- compatible, MAC, notebooks, and PDAs
• Resources - printers, fax machines, tape backup units, and file storage devices
• Cables - crossover, ethernet
• Connectors - bridges, routers
• Network Interface Card (NIC) - a card installed inside a computer that physically
connects a computer to a network and controls the flow of data from the network to
the computer. The NIC has a port where the network cable is connected.
Network Types
• LAN stands for Local Area Network. Local area refers to a network in one location,
Local Area Networks connect computers and devices close to each other such as on
one floor of a building, one building, or a campus. LANs can connect as few as two
computers or as many as 100 computers.
• WAN (Wide Area Network) connects LANs together. The networks that make up a
WAN can be located throughout a country or even around the world. If a single
company owns a WAN, it is often referred to as an enterprise network. The Internet is
currently the largest WAN.
Firewalls
A firewall is a software or hardware system that prevents unauthorized outside access,
theft, deletion, or modification of information stored on a local network. Typically,
unauthorized access would be via an organization’s Internet connection.
integrated_manual.book Page 178 Friday, October 12, 2001 2:56 PM