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Gateway 7001 Series User Manual

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IPSec

IP Security (IPSec) is a set of protocols to support the secure exchange of packets at the

IP

layer. It uses shared public keys. There are two encryption modes: Transport and Tunnel.

Transport mode encrypts only the data portion (payload) of each packet, but leaves the
headers untouched.

The more secure Tunnel mode encrypts both the header and the payload.

ISP

An Internet Service Provider (ISP) is a company that provides access to the Internet to
individuals and companies. It may provide related services such as virtual hosting, network
consulting, Web design, etc.

Jitter

Jitter is the difference between the latency (or delay) in packet transmission from one node
to another across a network. If packets are not transmitted at a consistent rate (including

Latency

),

QoS

for some types of data can be affected. For example, inconsistent

transmission rates can cause distortion in VoIP and streaming media.

QoS

is designed to

reduce jitter along with other factors that can impact network performance.

Latency

Latency, also known as delay, is the amount of time it takes to transmit a

Packet

from sender

to receiver.

Latency can occur when data is transmitted from the access point to a client and vice versa.
It can also occur when data is transmitted from access point to the Internet and vice versa.
Latency is caused by fixed network factors such as the time it takes to encode and decode
a packet, and also by variable network factors such as a busy or overloaded network.

QoS

features are designed to minimize latency for high priority network traffic.

LAN

A Local Area Network (LAN) is a communications network covering a limited area, for
example, the computers in your home that you want to network together or a couple of
floors in a building. A LAN connects multiple computers and other network devices such
as storage and printers.

Ethernet

is the most common technology implementing a LAN.

Wireless Ethernet (

802.11

) is another very popular LAN technology (also see

WLAN

).

LDAP

The Lightweight Directory Access Protocol (LDAP) is a protocol for accessing on-line directory
services. It is used to provide an authentication mechanism. It is based on the X.500
standard, but less complex.