DescriptionWhat is Virtual Cell Overflow and how to configure the same ?
ScopeKB ARTICLE TYPE:
Configuration
RELATED PRODUCTS:
NA
RELATED SOFTWARE VERSIONS: All
versions
KEYWORDS: vcell/ess
overflow
SolutionThis feature, called Vcell Overflow, works by pairing a
Virtual Cell ESS with a non-Virtual Cell ESS. The overflow ESS
automatically inherits the parameters of the Virtual Cell ESS
(except the setting for Virtual Cell). The non-Virtual
Cell ESS is not used unless the Virtual Cell ESS is maxed-out;
when this happens, the Virtual Cell ESS overflows into the other ESS as
needed. The two ESS Profiles share same SSID so that clients
seamlessly move back and forth. The overflow decision is based
on the percentage of airtime spent on beacons crossing a threshold; when
the percentage reaches 50%, clients start to
overflow
When to Use Virtual Cell
Overflow?
This feature is designed for a high density
deployment and provides a solution for bottlenecks caused by
transmitting beacons. Virtual Cell Overflow is useful in these
situations:
• Beacon overhead has become very high due to the
legacy b devices.
• A very dense network is consuming a lot of
airtime with beacons.
Be aware that Virtual Cell
Overflow has these tradeoffs:
• Trade-off between
mobility and performance
• Trade-off between density and
performance
• Not a solution to get good performance for
overflow clients
Configure Virtual Cell
Overflow with the Web
UI
To set
up Virtual Cell Overflow from the Web UI, follow these
steps:
1. Create
a Virtual Cell ESS.
Be sure that the setting for Virtual Cell is set to On.
2. Create
a non-Virtual Cell ESS.
Be sure that the setting for Virtual Cell is set to Off.
Make this an Overflow
ESS with the setting Overflow
for; select the ESS you created in Step 1.
This
overflow ESS
automatically inherits the remaining parameters of the Virtual
Cell
ESS.
Configure Virtual Cell Overflow with the
CLI
In the
CLI, a new command, overflowfrom-essprofile,
has been added for this
purpose. See the example
below.
default(0)# show
essid
ESS
Profile Name SSID Security
Profile
Broadcast
Tunnel Interface Type
vcelloverflow vcelloverflow
default
on
none
ESS Profile(1
entry)
default(0)# configure
terminal
default(0)(config)# essid
vcelloverflowoss
default(0)(config-essid)# overflowfrom- essprofile
vcelloverflow
default(0)(config-essid)# end
