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The conversion of information into a scrambled form that
effectively disguises it to prevent unauthorized access. Every encryption
scheme uses some well-defined algorithm, which is reversed at the receiving
end by an opposite algorithm in a process known as decryption.
end-to-end VLANs
VLANs that span the switch-fabric from end to end;
all switches in end-to-end VLANs understand about all configured VLANs.
End-to-end VLANs are configured to allow membership based on function,
project, department, and so on.
Enhanced IGRP
Enhanced Interior Gateway Routing Protocol: An
advanced routing protocol created by Cisco, combining the advantages of
link-state and distance-vector protocols. Enhanced IGRP has superior con-
vergence attributes, including high operating efficiency. See also: IGP,
and RIP.
enterprise network
A privately owned and operated network that joins
most major locations in a large company or organization.
enterprise services
Defined as services provided to all users on the inter-
network. Layer 3 switches or routers are required in this scenario because the
services must be close to the core and would probably be based in their own
subnet. Examples of these services include Internet access, e-mail, and pos-
sibly videoconferencing. If the servers that host these enterprise services were
placed close to the backbone, all users would have the same distance to them,
but this also means that all users' data would have to cross the backbone to
get to these services.
Erasable Programmable Read-Only Memory: Programmed after
their manufacture, these nonvolatile memory chips can be erased if necessary
using high-power light and reprogrammed. See also: EEPROM and PROM.
error correction
Error correction uses a checksum to detect bit errors in
the data stream.
Extended Superframe: Made up of 24 frames with 192 bits each, with
the 193rd bit providing other functions including timing. This is an
enhanced version of SF. See also: SF.
Copyright ©2001 SYBEX , Inc., Alameda, CA