Filter
Top Products
GL-15
Cisco Router and Security Device Manager 2.5 User’s Guide
OL-4015-12
Glossary
GRE
generic routing encapsulation. Tunneling protocol developed by Cisco that can
encapsulate a wide variety of protocol packet types inside IP tunnels, creating a
virtual point-to-point link to Cisco routers at remote points over an IP
internetwork. By connecting multiprotocol subnetworks in a single-protocol
backbone environment, IP tunneling using GRE allows network expansion
across a single-protocol backbone environment.
GRE over IPSec
This technology uses IPSec to encrypt GRE packets.
G.SHDSL
Also known as G.991.2, G.SHDSL is an international standard for symmetric
DSL developed by the International Telecommunications Union. G.SHDSL
provides for sending and receiving high-speed symmetrical data streams over a
single pair of copper wires at rates between 192 kbps and 2.31 Mbps.
H
H.323
An ITU-T standard that enables video conferencing over local-area networks
(LANs) and other packet-switched networks, as well as video over the Internet.
hash
One-way process that converts input of any size into checksum output of a fixed
size, called a message digest, or just a digest. This process is not reversible, and
it is not feasible to create or modify data to result in a specific digest.
hash algorithm
A hash algorithm is used to generate a hash value, also known as a message
digest, ensures that message contents are not changed during transmission. The
two most widely used types of hash algorithms are Secure Hash Algorithm
(SHA) and MD5)
HDLC
High-Level Data Link Control. Bit-oriented synchronous data link layer
protocol developed by the International Standards Organization (ISO). HDLC
specifies a data encapsulation method on synchronous serial links using frame
characters and checksums.
headend
The upstream, transmit end of a tunnel.