Netgear FVM318 – Cable and DSL ProSafe Wireless VPN Security Firewall 참조 매뉴얼

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Reference Manual for the Model FVM318 Cable/DSL ProSafe Wireless VPN Security Firewall
B-2
Network, Routing, Firewall, and Wireless Basics
 
What is a Router?
A router is a device that forwards traffic between networks based on network layer information in 
the data and on routing tables maintained by the router. In these routing tables, a router builds up a 
logical picture of the overall network by gathering and exchanging information with other routers 
in the network. Using this information, the router chooses the best path for forwarding network 
traffic.
Routers vary in performance and scale, number of routing protocols supported, and types of 
physical WAN connection they support. The FVM318 Cable/DSL ProSafe Wireless VPN Security 
Firewall is a small office router that routes the IP protocol over a single-user broadband 
connection.
Routing Information Protocol
One of the protocols used by a router to build and maintain a picture of the network is the Routing 
Information Protocol (RIP). Using RIP, routers periodically update one another and check for 
changes to add to the routing table.
The FVM318 firewall supports both the older RIP-1 and the newer RIP-2 protocols. Among other 
improvements, RIP-2 supports subnet and multicast protocols. RIP is not required for most home 
applications. 
IP Addresses and the Internet
Because TCP/IP networks are interconnected across the world, every machine on the Internet must 
have a unique address to make sure that transmitted data reaches the correct destination. Blocks of 
addresses are assigned to organizations by the Internet Assigned Numbers Authority (IANA). 
Individual users and small organizations may obtain their addresses either from the IANA or from 
an Internet service provider (ISP). You can contact IANA at www.iana.org.
The Internet Protocol (IP) uses a 32-bit address structure. The address is usually written in dot 
notation (also called dotted-decimal notation), in which each group of eight bits is written in 
decimal form, separated by decimal points.
For example, the following binary address: 
11000011  00100010  00001100  00000111 
is normally written as: