Technical data

© 2012 Meru Networks, Inc. Glossary 331
gateway
In the wireless world, a gateway is an access point with additional software capabilities
such as providing NAT and DHCP. Gateways may also provide VPN support, roaming, fire-
walls, various levels of security, etc.
H
Handoff
The transfer of a link from one access point to another as a client moves through a
network. In legacy microcell networks, Wi-Fi clients are responsible for handoff, meaning
that the quality of the link and the overall network performance is dependent on each
client's implementation of 802.11 roaming algorithms. In Virtual Cell and Virtual Port
networks, the network itself governs handoffs as clients remain connected to a single
virtual AP.
hotspot
A place where you can access Wi-Fi service. This can be for free or for a fee. HotSpots can
be inside a coffeeshop, airport lounge, train station, convention center, hotel or any other
public meeting area. Corporations and campuses are also implementing HotSpots to
provide wireless Internet access to their visitors and guests. In some parts of the world,
HotSpots are known as CoolSpots.
hub
A multiport device used to connect PCs to a network via Ethernet cabling or via Wi-Fi.
Wired hubs can have numerous ports and can transmit data at speeds ranging from 10 Mbps
to multigigabyte speeds per second. A hub transmits packets it receives to all the
connected ports. A small wired hub may only connect 4 computers; a large hub can
connect 48 or more. Wireless hubs can connect hundreds.
Hz
The international unit for measuring frequency, equivalent to the older unit of cycles per
second. One megahertz (MHz) is one million hertz. One gigahertz (GHz) is one billion hertz.
The standard US electrical power frequency is 60 Hz, the AM broadcast radio frequency
band is 535-1605 kHz, the FM broadcast radio frequency band is 88-108 MHz, and Wireless
802.11b LANs operate at 2.4 GHz.
I
IP number
Also called an IP address. A 32-bit binary number that identifies senders and receivers of
traffic across the Internet. It is usually expressed in the form
nnn.nnn.nnn.nnn where nnn
is a number from 0 to 256.
identity-based
networking
A concept whereby WLAN policies are assigned and enforced based upon a wireless client's
identity, as opposed to its physical location. With identity networking, wireless devices
need only authenticate once with a WLAN system. Context information will follow the
devices as they roam, ensuring seamless mobility.
IEEE
Institute of Electrical and Electronics Engineers. (www.ieee.org) A membership organiza-
tion that includes engineers, scientists and students in electronics and allied fields. It has
more than 300,000 members and is involved with setting standards for computers and
communications.
IEEE 802.11
A set of specifications for LANs from The Institute of Electrical and Electronics Engineers
(IEEE). Most wired networks conform to 802.3, the specification for CSMA/CD based
Ethernet networks or 802.5, the specification for token ring networks. 802.11 defines the
standard for Wireless LANs encompassing three incompatible (non-interoperable) technol-