Test-Um NT750 - Manual (Page 22)

LanScaper
TM
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
Target
TCP/IP
WAN
= Gateway - If a device is attempting to communicate with an IP address, and it finds 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.
- 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.
= Transmission Control Protocol/Internet Protocol
= 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 define the hardware path used to communicate with any IP-addressed device not on
the local LAN.