Nokia IP60 - Security Appliance, User Manual

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Glossary of Terms
Glossary of Terms 485
Mbps
Megabits per second. Measurement unit for the
rate of data transmission.
MTU
The Maximum Transmission Unit (MTU) is a
parameter that determines the largest datagram
than can be transmitted by an IP interface
(without it needing to be broken down into
smaller units). The MTU should be larger than
the largest datagram you wish to transmit un-
fragmented. Note: This only prevents
fragmentation locally. Some other link in the
path may have a smaller MTU - the datagram
will be fragmented at that point. Typical values
are 1500 bytes for an Ethernet interface or 1452
for a PPP interface.
N
NAT
Network Address Translation (NAT) is the
translation or mapping of an IP address to a
different IP address. NAT can be used to map
several internal IP addresses to a single IP
address, thereby sharing a single IP address
assigned by the ISP among several PCs.
Check Point FireWall-1's Stateful Inspection
Network Address Translation (NAT)
implementation supports hundreds of pre-
defined applications, services, and protocols,
more than any other firewall vendor.
NetBIOS
NetBIOS is the networking protocol used by
DOS and Windows machines.
P
Packet
A packet is the basic unit of data that flows from
one source on the Internet to another destination
on the Internet. When any file (e-mail message,
HTML file, GIF file etc.) is sent from one place
to another on the Internet, the file is divided into
"chunks" of an efficient size for routing. Each of
these packets is separately numbered and
includes the Internet address of the destination.
The individual packets for a given file may
travel different routes through the Internet.
When they have all arrived, they are
reassembled into the original file at the receiving
end.
PPPoE
PPPoE (Point-to-Point Protocol over Ethernet)
enables connecting multiple computer users on
an Ethernet local area network to a remote site
or ISP, through common customer premises
equipment (e.g. modem).
PPTP
The Point-to-Point Tunneling Protocol (PPTP)
allows extending a local network by establishing
private ―tunnels‖ over the Internet. This protocol
it is also used by some DSL providers as an
alternative for PPPoE.
R
RJ-45
The RJ-45 is a connector for digital transmission
over ordinary phone wire.
Router
A router is a device that determines the next
network point to which a packet should be
forwarded toward its destination. The router is
connected to at least two networks.
S
Server
A server is a program (or host) that awaits and
requests from client programs across the
network. For example, a Web server is the
computer program, running on a specific host,
that serves requested HTML pages or files. Your
browser is the client program, in this case.
Stateful Inspection
Stateful Inspection was invented by Check Point
to provide the highest level of security by
examining every layer within a packet, unlike
other systems of inspection. Stateful Inspection
extracts information required for security
decisions from all application layers and retains
this information in dynamic state tables for
evaluating subsequent connection attempts. In
other words, it learns!