User`s guide
33
ISP = Internet Service Provider - Commercial supplier of access
mechanisms for public access to the internet.
LAN = Local Area Network - Connection mechanism for a business, home,
school or any group of devices to communicate with each other. In the
LanScaper™ case, it is a group of computers, printers, routers and possibly
other devices connected by Ethernet. Distinct from the WAN due to the IP
addressing in a “Subnet”.
Network Mask = Subnet Mask - IP addressing scheme that divides the
entire IP address network into smaller sections (Subnets). In the case
of the LanScaper™, the Network mask is used to identify an IP address
as being located either on the LAN (local subnet) or on the Internet, and
therefore accessed over the WAN.
PING = Packet INternet Groper - A simple communication protocol (ICMP
Echo) used to request an echo back from an addressed device (target).
The LanScaper™ uses this to verify IP connectivity between itself and
another device.
Router = Gateway - If a device is attempting to communicate with an IP
address, and it nds that the target is not on its local network (by comparing
the target address with it’s own address and the Netmask) the device must
forward it’s request to a router. The router forwards the communication to
the target device across the WAN. This typically puts the communications
on the internet, but may also be another LAN subnet, or a private network
of some other type. A router has an IP address and MAC address (on
Ethernet) of its own for direct communications, which differentiates it from a
HUB or switch. A hardware box sold as a router will usually include a HUB
or switch chip inside, providing a convenient connection point for multiple
Ethernet devices.
Target - In the PING protocol, an IP address must be selected to receive
an echo request. This address is the “target” address for that PING. In the
LanScaper™, a target must be selected manually in Setup. This target can
be on the LAN, or anywhere else accessible through a router connected
to the LAN. If the target is not on the LAN, the router IP address must be
known so the PING can be sent to the router which forwards it on toward
the ultimate location.
TCP/IP = Transmission Control Protocol/Internet Protocol
WAN = Wide Area Network - The “remote” interface on a router. The WAN
may be accessed via a DSL line, broadband cable connection, ISDN, T1
line or even a dial-up modem line. This term is used to loosely dene the
hardware path used to communicate with any IP-addressed device not on
the local LAN.