
18
Introduction
Figure 1-2
802.11a versus 802.11b Coverage Area
Limitations on Roaming
Roaming is the ability of a wireless client to move from one Access Point to another while maintaining an uninterrupted
connection to the network. Most traditional Access Points support this feature. While the AP-2500 supports seamless
roaming from a radio perspective, in practice it does not support seamless roaming for subscribers from AP-2500 to
AP-2500 in a hotspot environment. Each AP-2500 maintains its own list of current subscribers that can access the
Internet; this list is not shared between AP-2500s.
Limited roaming can be achieved under the following circumstances:
1.
A subscriber can seamlessly roam between two radios installed in the AP-2500. For example, a subscriber
with an 802.11b client can roam between the Access Point’s two 802.11b cells when two 802.11b cards are
installed. (This assumes that the two cells have the same Network Name and Encryption settings.)
2.
If you use a RADIUS server to authenticate subscribers, a subscriber can move between multiple AP-2500s
but the user will need to re-login each time he connects to a different Access Point. This solution does not
provide seamless roaming.
NOTE:
If you have enabled the
Information and Control Console (ICC)
, a RADIUS user who clicks the
Logout
button
will not be logged out following a roam from one AP-2500 to another. The user will need to browse new pages
to bring up the login screen for the new AP and re-login when prompted.
List of Networking Features
The IEEE standards that governs wireless communications are different for the 2.4 GHz band and the 5 GHz band.
The table below compares the software features supported for each type of card in the AP-2500 device:
Feature
2.4 GHz
(802.11b)
5 GHz
(802.11a)
Comments
Number of stations per BSS
up to 250
up to 50
This specifies the limits of each radio. Note that the
AP-2500’s Public Space features can support a
maximum of 100 subscribers.
HTTP Server
yes
yes
Telnet / CLI
yes
yes
SNMP Agent
yes
yes
VLAN Support (2 User VLANs)
yes
yes
Emergency Reset to Default Configuration
yes
yes