User's Manual

66xx/67xx Router Users Guide 180
suite of protocols.
Telnet An interactive, character-based program used to access a remote
computer. While HTTP (the web protocol) and FTP only allow you to
download files from a remote computer, Telnet allows you to log into and
use a computer from a remote location.
TFTP Trivial File Transfer Protocol
A protocol for file transfers, TFTP is easier to use than File Transfer
Protocol (FTP) but not as capable or secure.
TKIP Temporal Key Integrity Protocol (TKIP) provides WPA with a data
encryption function. It ensures that a unique master key is generated for
each packet, supports message integrity and sequencing rules and
supports re-keying mechanisms.
Triggers Triggers are used to deal with application protocols that create separate
sessions. Some applications, such as NetMeeting, open secondary
connections during normal operations, for example, a connection to a
server is established using one port, but data transfers are performed on
a separate connection. A trigger tells the device to expect these
secondary sessions and how to handle them.
Once you set a trigger, the embedded IP address of each incoming
packet is replaced by the correct host address so that NAT can translate
packets to the correct destination. You can specify whether you want to
carry out address replacement, and if so, whether to replace addresses
on TCP packets only, UDP packets only, or both.
Twisted pair The ordinary copper telephone wiring used by telephone companies. It
contains one or more wire pairs twisted together to reduce inductance and
noise. Each telephone line uses one pair. In homes, it is most often
installed with two pairs. For Ethernet LANs, a higher grade called
Category 3 (CAT 3) is used for 10BASE-T networks, and an even higher
grade called Category 5 (CAT 5) is used for 100BASE-T networks. See
10BASE-T, 100BASE-T, Ethernet.
Unnumbered interfaces An unnumbered interface is an IP interface that does not have a local
subnet associated with it. Instead, it uses a router-id that serves as the
source and destination address of packets sent to and from the router.
Unlike the IP address of a normal interface, the router-id of an
unnumbered interface is allowed to be the same as the IP address of
another interface. For example, the WAN unnumbered interface of your
device uses the same IP address of the LAN interface (192.168.1.1).
The unnumbered interface is temporary – PPP or DHCP will assign a
‘real’ IP address automatically.
Upstream The direction of data transmission from the user to the Internet.
VC Virtual Circuit
A connection from your DSL router to your ISP.
VCI Virtual Circuit Identifier
Together with the Virtual Path Identifier (VPI), the VCI uniquely identifies a
VC. Your ISP will tell you the VCI for each VC they provide. See VC.
VDSL Very High Speed Digital Subscriber Line
It provides faster transmission rate and is capable of supporting high
bandwidth applications like IPTV and bandwidth consumed applications.