an intruder can be monitored or blocked from access. One trigger for an
intruder detection system is multiple ping packets from a single resource in
a brief period of time.
a router to locate the logical network address and associate it with a perma-
nent virtual circuit (PVC). Commonly used in Frame Relay to determine the
far-end node's TCP/IP address by sending the Inverse ARP request to the
local DLCI.
nishes an array of features for addressing, type-of-service specification, frag-
mentation and reassembly, and security.
address consists of four octets (32 bits), represented as decimal numbers sep-
arated by periods (a format known as "dotted-decimal"). Every address is
made up of a network number, an optional subnetwork number, and a host
number. The network and subnetwork numbers together are used for
routing, while the host number addresses an individual host within the net-
work or subnetwork. The network and subnetwork information is extracted
from the IP address using the subnet mask. There are five classes of IP
addresses (AE), which allocate different numbers of bits to the network,
subnetwork, and host portions of the address. See also: CIDR, IP, and
subnet mask.
many destinations. Instead of transmitting only one packet to each indi-
vidual point of destination, one packet is sent to a multicast group specified
by only one IP endpoint address for the group.