Roaming And Handover - Avaya Communication Server 1000 Installation And Commissioning Manual

Roaming and handover

Roaming is the ability of the wireless handset to go anywhere in the WLAN Extended Service
Set RF signal coverage area, and to make and receive calls. Handover is the ability of the
wireless handset to maintain an active call without interruption while moving within a WLAN
Extended Service Set (ESS) RF signal coverage area of a WLAN. This means that the wireless
handset hands over the WLAN RF signal from AP to AP without interrupting the data stream.
Access points on the same subnet
The handset can perform handover and roaming across SVP-compliant APs that reside on the
same subnet as the wireless handset and WLAN IP Telephony Manager 2245 group.
Mobility across different subnets when using DHCP
If a WSS is not in use and the wireless handset IP address is acquired through DHCP, the
wireless handset must be powered down and powered up when entering a new subnet. This
enables functionality of the wireless handset when entering the WLAN RF signal coverage
area of a different WLAN IP Telephony Manager 2245 group on a different subnet. After the
wireless handset establishes communication within the Extended Service Set Identifier
(ESSID) of the new WLAN, obtains another IP address from the DHCP server, and checks in
with the group master, normal functionality returns. If the wireless handset is configured to use
ESSID of the new WLAN, it automatically discovers the ESSID of the APs operating in
broadcast mode.
Table 10: Roaming and handover capabilities summary
capabilities.
Table 10: Roaming and handover capabilities summary
IP address
Static
Static
DHCP
DHCP
Avaya WLAN IP Telephony Installation and Commissioning
WSS in use Roaming capability Handover capability
No No
Yes Yes
No Yes, if the wireless
handset is power-
cycled between
subnets.
Yes Yes
WLAN IP Telephony Manager 2245 planning
on page 73 summarizes the
No
Yes
No
Yes
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