Air Live Router WT-2000ARM User Manual

							 
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Chapter VII: Glossary 
10Base-T 
It is an Ethernet standard for Local Area Network (LAN). 10Base-T uses a twisted pair cable with 
maximum length of 100 meters. 
 
AAL 
ATM Adaptation Layer that defines the rules governing segmentation and reassembly of data into cells. 
Different AAL types are suited to different traffic classes. 
 
ADSL 
Asymmetric Digital Subscriber Line, as its name showing, is an asymmetrical data transmission 
technology with high traffic rate downstream and low traffic rate upstream. ADSL technology satisfies 
the bandwidth requirement of applications, which demand “asymmetric” traffic, such as web surfing, 
file download and Video-on-demand (VOD). 
 
ATM  
Asynchronous Transfer Mode is a layer 2 protocol supporting high-speed asynchronous data with 
advanced traffic management and quality of service features. 
 
bps 
Bits per second, a standard measurement of digital transmission speeds. 
 
Bridge 
A device that connects two or more physical networks and forwards packets between them. Bridges 
can usually be made to filter packets, that is, to forward only certain traffic. Related devices are: 
repeaters which simply forward electrical signals from one cable to the other and full-fledged routers 
which make routing decisions based on several criteria. 
 
CPE 
Customer Premises Equipment, such as ADSL router, USB modem. 
 
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. 
 
  
						

							 
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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 Broadbandrouter.com 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 
Digital Line Subscriber (DSL) technology provides high-speed access over twisted copper pair for 
connection to the Internet, LAN interfaces, and to broadband services such as video-on-demand, 
distance learning, and video conferencing. 
 
Ethernet 
It is a standard for computer networks. Ethernet networks are connected by special cables and hubs 
or switches, and move data around at up to 10/100 million bits per second (Mbps).  
 
FTP 
File Transfer Protocol. The Internet protocol (and program) used to transfer files between hosts. 
 
Idle Timeout 
Idle Timeout is designed so that after there is no traffic to the Internet for a pre-configured amount of 
time, the connection will automatically be disconnected. 
 
ISP 
Internet Service Provider is a business that provides connectivity to the Internet for individuals and 
other businesses or organizations.  
 
ISP Gateway Address 
The ISP Gateway Address is an IP address for the Internet router located at the ISPs office.  
 
LAN 
Local Area Network is a group of computers and devices connected together in a relatively small area 
(such as a house or an office). Your home network is considered a LAN.   
						

							 
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MAC Address 
MAC stands for Media Access Control. A MAC address is the hardware address of a device 
connected to a network. The MAC address is a unique identifier for a device with an Ethernet interface. 
It is comprised of two parts: 3 bytes of data that corresponds to the Manufacturer ID (unique for each 
manufacturer), plus 3 bytes that are often used as the product’s serial number. 
 
MTU 
Maximum Transmission Unit 
 
NAT 
Network Address Translator is defined by RFC 1631. Enable a LAN network to use one set of IP 
address for internal traffic. A NAT box located where the LAN meets the Internet provides the 
necessary IP address translation. This helps provide a sort of firewall and allow for a wider address 
range to be used internally without danger of conflict. Using the router’s NAT capability, you can 
access the Internet from any computer on your home network without having to purchase more IP 
addresses from your ISP. 
 
Port 
Network Clients (LAN PC) uses port numbers to distinguish one network application/protocol over 
another. Below is a list of common applications and protocol/port numbers: 
 
Application Protocol Port Number
Telnet TCP 23 
FTP TCP 21 
SMTP TCP 25 
POP3 TCP 110 
H.323 TCP 1720 
SNMP UCP 161 
SNMP Trap  UDP  162 
HTTP TCP 80 
PPTP TCP 1723 
PC Anywhere TCP  5631 
PC Anywhere UDP  5632 
 
PPP 
PPP is the Point-to-Point-Protocol. The successor to SLIP, PPP provides router-to-router and host-to-
network connections over both synchronous and asynchronous circuits.  
						

							 
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PPPoA (RFC 2364) 
The Point-to-Point Protocol (PPP) provides a standard method for transporting multi-protocol data 
grams over point-to-point links. This document describes the use of ATM Adaptation Layer 5 (AAL5) 
for framing PPP encapsulated packets. 
 
PPPoE (RFC 2516) 
This document describes how to build PPP sessions and encapsulate PPP packets over Ethernet. 
PPP over Ethernet (PPPoE) provides the ability to connect a network of hosts over a simple bridging 
access device to a remote Access Concentrator. 
 
Protocol 
A protocol is a set of rules for interaction agreed upon between multiple parties so that when they 
interface with each other based on such a protocol, the interpretation of their behavior is well defined 
and can be made objectively, without confusion or misunderstanding.  
 
PVC 
Permanent Virtual Circuit, connection-oriented permanent leased line circuit between end-stations on 
a network over a separate ATM circuit. 
 
RFC 
Request for Comments. The document series, begun in 1969, which describes the Internet suite of 
protocols and related experiments. Not all RFCs describe Internet standards, but all Internet standards 
are written up as RFCs. 
 
RFC 1483 
Multi-protocol encapsulation over AAL-5. Two encapsulation methods for carrying network 
interconnect traffic over ATM AAL-5. The first method allows multiplexing of multiple protocols over a 
single ATM virtual circuit. The protocol of a carried PDU is identified by prefixing the PDU by an IEEE 
802.2 Logical Link Control (LLC) header. This method is in the following called LLC Encapsulation. 
The second method does higher-layer protocol multiplexing implicitly by ATM Virtual Circuits (VCs). It 
is in the following called VC Based Multiplexing. 
 
Router 
A system responsible for making decisions about which of several paths network (or Internet) traffic 
will follow. To do this, it uses a routing protocol to gain information about the network and algorithms to 
choose the best route based on several criteria known as routing metrics. 
  
						

							 
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Subnet Mask 
A subnet mask, which may be a part of the TCP/IP information provided by your ISP, is a set of four 
numbers (e.g. 255.255.255.0) configured like an IP address. It is used to create IP address numbers 
used only within a particular network (as opposed to valid IP address numbers recognized by the 
Internet, which must be assigned by InterNIC).  
 
TCP/IP, UDP 
Transmission Control Protocol/Internet Protocol (TCP/IP) and Unreliable Datagram Protocol (UDP). 
TCP/IP is the standard protocol for data transmission over the Internet. Both TCP and UDP are 
transport layer protocol. TCP performs proper error detection and error recovery, and thus is reliable. 
UDP on the other hand is not reliable. They both run on top of the IP (Internet Protocol), a network 
layer protocol. 
 
TELNET 
It is the virtual terminal protocol in the Internet suite of protocols. Allows users of one host to log into a 
remote host and act as normal terminal users of that host. 
 
VCI 
Virtual Circuit Identifier is part of the ATM cell header. A VCI is a tag indicating the channel over which 
a cell will travel. The VCI of a cell can be changed as it moves between switches via Signaling. 
 
VPI 
Virtual Path Identifier is part of the ATM cell header. A VPI is a pipe for a number of Virtual Circuits. 
 
WAN 
Wide Area Network is a network that connects computers located in geographically separate areas 
(e.g. different buildings, cities, countries). The Internet is a wide area network. 
 
Web-based management Graphical User Interface (GUI) 
Many devices support a graphical user interface that is based on the web browser. This means the 
user can use the familiar Netscape or Microsoft Internet Explorer to Control/configure or monitor the 
device being managed.