User Manual

6 Introduction to the Extricom Wireless LAN System
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 Centralized configuration
New switches are added to the network via a single Web interface either manually by the user,
or automatically using an Extricom protocol.
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 System redundancy
Extricom enables full redundancy by connecting two switches in a cascade or hot-standby
topology. The switchover parameters are user-configurable
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 SNMP
The Extricom system supports SNMP V2 based on standard and private MIBs, enabling the
user to configure the switch using SNMP Set operations, read switch status using SNMP Get
operation and determine the status of the system, including the status of APs and Redundancy,
using SNMP Traps. SNMP is provided for customers wishing to use their existing network
management system to administer multiple Extricom switches. Alternatively, the Extricom
EXNM-2000 network management software platform is available as a dedicated centralized
Extricom WLAN management system.
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 Multiple RADIUS & RADIUS Redundancy
The Extricom system supports multiple RADIUS servers per ESSID, enabling the user to set
redundancy between these RADIUS servers.
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 Network Time Protocol (NTP)
The Extricom system supports synchronization of the system clock over the network, thereby
ensuring accurate local time keeping with reference to radio and atomic clocks located on the
Intranet and/or Internet.
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 Fast Handoff (Opportunistic Key Caching) - WLAN clients roaming between APs of the
same channel blanket within a single switch’s coverage area will experience zero-latency
mobility. Clients roaming between different Extricom WLAN switches use the standard 802.11
handoff mechanism, which is further facilitated by the opportunistic key caching mechanism in
the 802.11i standard. In addition to this, the Extricom system speeds up 802.11i handoff
between Extricom switches by use of Extricom’s inter-switch protocol. This permits the client
to avoid repetitive 802.1x authentications, thereby enabling faster transition between Access
Points connected to different switches with minimal session interruption
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 Captive Portal – The Captive Portal technique compels any HTTP client to view a special web
page (usually for authentication purposes) before accessing the rest of the network. Captive
Portal turns a Web browser into a secure authentication device. This is done by intercepting an
internet access request and redirecting it to an Extricom local logging web page which may
require authentication, or simply display an acceptable use policy and require the user to agree.
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 MAC authentication – MAC authentication technique enables the Extricom switch to
authenticate WLAN devices via RADIUS server even if they have no native support for 802.1x.
This mechanism is normally used in “dumb” device WLAN topology (such as barcode readers)
where WLAN client authentication is to be managed via a central RADIUS server.