- LG Software Innovations Coffeemaker User Manual

Description Page 55 of
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ITG Trunk 2.0 ISDN Signaling Link (ISL) Description, Installation and Operation
Bandwidth
Bandwidth is a measure of information carrying capacity available for a
transmission medium. The greater the bandwidth the more information that
can be sent in a given amount of time. Bandwidth is expressed in bits per
second (bps).
Network performance utilities
Two common network performance utilities, PING and Traceroute, are
described below. Other utilities can be used to gather information about ITG
network performance.
Note: These descriptions are for reference purposes only. Traceroute is
not part of the ITG product.
Because network conditions can vary over time, collect performance data
over a period of at least four hours. Use performance utilities to measure
network performance from each ITG node to every other ITG node in your
network.
Packet InterNet Groper (PING)
Packet InterNet Groper (PING) sends an Internet Control Message Protocol
(ICMP) echo request message to a host, expecting an ICMP echo reply. This
allows the measurement of the round-trip time to a selected host. By sending
repeated ICMP echo request messages, the percentage of packet loss for a
route can be measured.
Traceroute
Traceroute uses the IP Time-to-Live (TTL) field to forward router hops to a
specific IP address. A router must not forward an IP packet with a TTL field
of 0 or 1. It must, instead, discard the packet and return an ICMP “time
exceeded” message to the originating IP address. Traceroute uses this
mechanism by sending an IP datagram with a TTL of 1 to the specified
destination host. The first router to handle the datagram returns a “time
exceeded” message. This identifies the first router on the route. Traceroute
sends out a datagram with a TTL of 2. This causes the second router on the
route to return a “time exceeded” message, and so on, until all hops have been
identified. The traceroute IP datagram has a Port number unlikely to be in use
at the destination (usually >30,000). This causes the destination to return a