Standby Management; Wlan To Vlan Mapping - Symbol WS5000 Series System Reference Manual

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WS5000 Series Switch System Reference Guide
battery power by sensing only for their specific BSS rather than all traffic. An access port with multiple BSSs
provides the same functionality as four single-BSS Access Points and requires less time for installation and
configuration.
Network administrators add WLANs to BSSs. The BSSIDs are mapped to ESSIDs by default. However, the
network administrator can optionally change default settings. The network administrator can map each BSSID
to multiple ESSIDs, so the radios on the access ports support multiple WLANs.
As RF traffic changes over time or the MU roams, the MU searches for access ports that have a matching
ESSID. The MU associates with an access port with the same ESSID to synchronize communication. As the
MU roams from coverage area to coverage area, it switches between access ports.
The MU switches between access ports when the MU analyzes the reception quality at a location and decides
to communicate with another access port based on the best signal strength and lowest MU load distribution.
The AP 100, AP 200, AP 300, AP 4121 and AP 4131 access ports support multiple ESSIDs.

1.3.6 Standby Management

"Failover" or Standby Management enables the network administrator to significantly reduce the chance of a
disruption in service to the switch and associated MUs by placing one or more additional WS5000 Series
Switches as backup to a Primary wireless switch if it fails.
After configuring a Primary and Standby switch, the Primary switch issues a Discovery packet on each
configured interface. Assuming there is a properly configured Standby switch, the Standby receives the
Discover packet and starts sending heartbeats to the Primary. This establishes connectivity between the
Primary and the Standby. The Primary switch executes various internal monitors, in addition to any necessary
to communicate with the Standby switch.
If heartbeats fail after being properly established, a failover event is incurred by the Standby wireless switch,
and thus assumes the duties of the Primary switch including adopting all access ports. The Standby switch
sends an administrative alert—SNMP trap, etc.—to the administrator that a failover event has taken place.
Warning! You cannot configure a WS5000 model switch as a standby for a
WS5100 model switch.

1.3.7 WLAN to VLAN Mapping

Virtual LANs (VLANs) segment large subnets of a network, which enables network administrators to control
broadcasts and heighten network security. The WS5000 Series switch connects to the wired network through
one of two Ethernet ports (typically through NIC 2). Each access port associated with the switch can be
connected to either a trunked or non-trunked Ethernet port of the switch. Administrators configure an Ethernet
policy so it maps each WLAN to a non-trunked Ethernet port or to one of the VLANs visible to the trunked
Ethernet port. Further, administrators enable WLANs to communicate with a VLAN by configuring each WLAN
so that the rest of the network connects through a common router or Layer 2 switch.
Access ports in a VLAN are able to broadcast and multicast only within that VLAN. Using VLANs, wireless
switch administrators limit the general traffic in the wireless network, including broadcast packets because
large numbers of broadcast packets can affect network performance. By segmenting a network into VLANs,
wireless switch administrators limit the spread of broadcast packets.