Technical data

332 Meru System Director Configuration Guide © 2012 Meru Networks, Inc.
ogies: Frequency Hopping Spread Spectrum (FHSS), Direct Sequence Spread Spectrum
(DSSS) and Infrared. WECA's focus is on 802.11b, an 11 Mbps high-rate DSSS standard for
wireless networks.
infrastructure
mode
A client setting providing connectivity to an AP. As compared to Ad-Hoc mode, whereby
PCs communicate directly with each other, clients set in Infrastructure Mode all pass data
through a central AP. The AP not only mediates wireless network traffic in the immediate
neighborhood, but also provides communication with the wired network. See Ad-Hoc and
AP.
IP
Internet Protocol. A set of rules used to send and receive messages at the Internet address
level.
IP telephony
Technology that supports voice, data and video transmission via IP-based LANs, WANs, and
the Internet. This includes VoIP (Voice over IP).
IP address
A 32-bit number that identifies each sender or receiver of information that is sent across
the Internet. An IP address has two parts: an identifier of a particular network on the
Internet and an identifier of the particular device (which can be a server or a workstation)
within that network.
IPSec
IPSec is a security protocol from the Internet Engineering Task Force (IETF) that provides
authentication and encryption. IPsec, which works at Layer 3, is widely used to secure
VPNs and wireless users. Some vendors, like Airespace, have implemented special WLAN
features that allow IPsec sessions to roam with clients for secure mobility.
ISDN
A type of broadband Internet connection that provides digital service from the customer's
premises to the dial-up telephone network. ISDN uses standard POTS copper wiring to
deliver voice, data or video.
ISO network
model
A network model developed by the International Standards Organization (ISO) that consists
of seven different levels, or layers. By standardizing these layers, and the interfaces in
between, different portions of a given protocol can be modified or changed as technologies
advance or systems requirements are altered. The seven layers are:
 Physical
 Data Link
 Network
 Tra ns po rt
 Session
 Presentation
 Application
The IEEE 802.11 Standard encompasses the physical layer (PHY) and the lower portion of
the data link layer. The lower portion of the data link layer is often referred to as the
Medium Access Controller (MAC) sublayer.