Glossary - Planet XRT-401C User Manual

XRT C Series User Manual
If this does solve the problem you can use the DMZ function. This should
work with almost every application, but:
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Glossary

Bridge: A bridge is an intelligent, internetworking device that forwards or filters packets
between different networks based on data link layer (MAC) address information.
Default Gateway (Router): Every non-router IP device needs to configure a default gateway's
IP address. When the device sends out an IP packet, if the destination is not on the same
network, the device has to send the packet to its default gateway, which will then send it out
towards the destination.
DHCP: Dynamic Host Configuration Protocol. This protocol automatically gives every
computer on your home network an IP address.
DNS Server IP Address: DNS stands for Domain Name System, which allows Internet
servers to have a domain name (such as www.Broadbandrouter.com) and one or more IP
addresses (such as 192.34.45.8). A DNS server keeps a database of Internet servers and their
respective domain names and IP addresses, so that when a domain name is requested (as in
typing "www.planet.com.tw" into your Internet browser), the user is sent to the proper IP
address. The DNS server IP address used by the computers on your home network is the
location of the DNS server your ISP has assigned to you.
DSL Modem: DSL stands for Digital Subscriber Line. A DSL modem uses your existing
phone lines to transmit data at high speeds.
Ethernet: A standard for computer networks. Ethernet networks are connected by special
cables and hubs, and move data around at up to 10/100 million bits per second (Mbps).
IP Address and Network (Subnet) Mask: IP stands for Internet Protocol. An IP address
consists of a series of four numbers separated by periods, that identifies a single, unique
Internet computer host in an IP network. Example: 192.168.0.1. It consists of 2 portions: the IP
network address, and the host identifier.
The IP address is a 32-bit binary pattern, which can be represented as four cascaded decimal
numbers separated by ".": aaa.aaa.aaa.aaa, where each "aaa" can be anything from 000 to 255,
or as four cascaded binary numbers separated by ".": bbbbbbbb.bbbbbbbb.bbbbbbbb.bbbbbbbb,
where each "b" can either be 0 or 1.
A network mask is also a 32-bit binary pattern, and consists of consecutive leading
1's followed by consecutive trailing 0's, such as
11111111.11111111.11111111.00000000. Therefore sometimes a network mask can also be
described simply as "x" number of leading 1's.
When both are represented side by side in their binary forms, all bits in the IP address that
correspond to 1's in the network mask become part of the IP network address, and the
remaining bits correspond to the host ID.
For example, if the IP address for a device is, in its binary form,
11011001.10110000.10010000.00000111, and if its network mask is,
11111111.11111111.11110000.00000000
It means the device's network address is
11011001.10110000.10010000.00000000, and its host ID is,
It is a security risk, since the firewall is disabled.
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