NetComm NB9 User Manual page 96

Filtering
fi ltering rule
Firewall
FTP
GGP
Gbps
GRE
hop
hop count
host
HTTP
ICMP
IGMP
96
To screen out selected types of data, based on fi ltering
rules. Filtering can be applied in one direction (upstream
or down stream), or in both directions.
A rule that specifi es what kinds of data a routing device
will accept and/or reject. Filtering rules are defi ned to
operate on an interface (or multiple interfaces) and in a
particular direction (upstream, downstream, or both).
Any method of protecting a computer or LAN connected
to the Internet from intrusion or attack from the outside.
Some fi rewall protection can be provided by packet fi lter-
ing and Network Address Translation services.
File Transfer Protocol - A program used to transfer fi les
between computers connected to the Internet. Common
uses include uploading new or updated fi les to a web
server, and downloading fi les from a web server.
Gateway to Gateway Protocol. An Internet protocol that
specifi es how gateway routers communicate with each
other.
Abbreviation for Gigabits (GIG-uh-bits) per second, or
one billion bits per second. Internet data rates are often
expressed in Gbps.
Generic Routing Encapsulation. TCP/IP protocol suite,
transport layer encapsulation protocol.
When you send data through the Internet, it is sent fi rst
from your computer to a router, and then from one router
to another until it fi nally reaches a router that is directly
connected to the recipient. Each individual "leg" of the
data's journey is called a hop.
The number of hops that data has taken on its route to its
destination. Alternatively, the maximum number of hops
that a packet is allowed to take before being discarded ,
See also TTL.
A device (usually a computer) connected to a network.
Hyper-Text Transfer Protocol HTTP is the main protocol
used to transfer data from web sites so that it can be
displayed by web browsers. See also web browser
Internet Control Message Protocol An Internet protocol
used to report errors and other network-related informa-
tion. The ping command makes use of ICMP.
Internet Group Management Protocol An Internet protocol
that enables a computer to share information about its
membership in multicast groups with adjacent routers.
A multicast group of computers is one whose members
have designated as interested in receiving specifi c con-
tent from the others. Multicasting to an IGMP group can
be used to simultaneously update the address books of
a group of mobile computer users or to send company
newsletters to a distribution list.
NB9/NB9W ADSL2+ VoIP Router
YML790 Rev1