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Gateway 7001 Series User Manual

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An infrastructure mode framework can be provided by a single access point (

BSS

) or a

number of access points (

ESS

).

Intrusion Detection

The Intrusion Detection System (IDS) inspects all inbound network activity and reports
suspicious patterns that may indicate a network or system attack from someone attempting
to break into the system. It reports access attempts using unsupported or known insecure
protocols.

IP

The Internet Protocol (IP) specifies the format of packets, also called datagrams, and the
addressing scheme. IP is a connectionless, best-effort packet switching protocol. It provides
packet routing, fragmentation and re-assembly. It is combined with higher-level protocols,
such as

TCP

or

UDP

, to establish the virtual connection between destination and source.

The current version of IP is IPv4. A new version, called IPv6 or IPng, is under development.
IPv6 is an attempt to solve the shortage of IP addresses.

IP Address

Systems are defined by their IP address, a four-byte (octet) number uniquely defining each
host on the Internet. It is usually shown in form 192.168.2.254. This is called
dotted-decimal notation.

An IP address is partitioned into two portions: the network prefix and a host number on
that network. A

Subnet Mask

is used to define the portions. There are two special host

numbers:

The Network Address consists of a host number that is all zeroes (for example,
192.168.2.0).

The Broadcast Address consists of a host number that is all ones (for example,
192.168.2.255).

There are a finite number of IP addresses that can exist. Therefore, a local area network
typically uses one of the

IANA

-designated address ranges for use in private networks. These

address ranges are:

10.0.0.0 to 10.255.255.255

172.16.0.0 to 172.31.255.255

192.168.0.0 to 192.168.255.255

A

Dynamic IP Address

is an IP address that is automatically assigned to a host by a

DHCP

server or similar mechanism. It is called dynamic because you may be assigned a different
IP address each time you establish a connection.

A

Static IP Address

is an IP address that is hard-wired for a specific host. A static address

is usually required for any host that is running a server, for example, a Web server.