SnapGear 1.7.8 manual Lan

Term	Meaning
	millions of people worldwide. The Internet is technically distinguished
	because it uses the TCP/IP set of protocols.
Intranet	A private TCP/IP network within an enterprise.
IPSec	Internet Protocol Security. IPSec provides interoperable, high quality,
	cryptographically-based security at the IP layer and offers protection
	for network communications.
LAN	Local Area Network.
LED	Light-Emitting Diode.
MAC address	The hardware address of an Ethernet interface. It is a 48-bit number
	usually written as a series of 6 hexadecimal octets, e.g.
	00:d0:cf:00:5b:da. A SnapGear appliance has a MAC address for
	each Ethernet interface. These are listed on a label on the
	underneath of the device.
Masquerade	The process when a gateway on a local network modifies outgoing
	packets by replacing the source address of the packets with its own
	IP address. All IP traffic originating from the local network appears to
	come from the gateway itself and not the machines on the local
	network.
NAT	Network Address Translation. The translation of an IP address used
	on one network to an IP address on another network. Masquerading
	is one particular form of NAT.
Net mask	The way that computers know which part of a TCP/IP address refers
	to the network, and which part refers to the host range.
NTP	Network Time Protocol (NTP) used to synchronize clock times in a
	network of computers.
PAT	Port Address Translation. The translation of a port number used on
	one network to a port number on another network.
PPP	Point-to-Point Protocol. A networking protocol for establishing simple
	links between two peers.
PPPoE	Point to Point Protocol over Ethernet. A protocol for connecting users
	on an Ethernet to the Internet using a common broadband medium
	(e.g. single DSL line, wireless device, cable modem, etc).
PPTP	Point to Point Tunneling Protocol. A protocol developed by
	Microsoft™ that is popular for VPN applications. Although not
	considered as secure as IPSec, PPP is considered “good enough”
	technology. Microsoft has addressed many flaws in the original
	implementation.
Road warrior	A remote machine with no fixed IP address.
Router	A network device that moves packets of data. A router differs from
	hubs and switches because it is “intelligent” and can route packets to
	their final destination.
Subnet mask	See “Net mask”.
Switch	A network device that is similar to a hub, but much smarter. Although

3

Introduction