Cisco Cisco Cius 4G 디자인 가이드
Cisco Cius Wireless Deployment Guide
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It is recommended to perform a spectrum analysis to ensure that the desired bands can be enabled in order to perform interband
roaming.
roaming.
Multicast
When enabling multicast in the wireless LAN, performance and capacity must be considered.
If there is an associated client that is in power save mode, then all multicast packets will be queued until the DTIM period.
If proxy ARP from CCX is enabled and Cisco Cius is not participating in a multicast session currently, then the access point is
responsible to answer any ARP requests on behalf of the client and Cisco Cius can remain in sleep mode longer thus optimizing
battery life.
If there are many packets queued up, then they client may have to stay awake longer thus potentially reducing battery life.
With multicast, there is no guarantee that the packet will be received the by the client.
The multicast traffic will be sent at the highest mandatory / basic data rate enabled on the access point, so will want to ensure
that only the lowest enabled rate is configured as the only mandatory / basic rate.
The client will send the IGMP join request to receive that multicast stream. The client will send the IGMP leave when the
session is to be ended.
Cisco Cius supports the IGMP query feature, which can be used to reduce the amount of multicast traffic on the wireless LAN
when not necessary.
Ensure that IGMP snooping is also enabled on all switches.
It is recommended to enable Multicast Direct in the Cisco Unified Wireless LAN Controller.
Note: If using Coexistence where 802.11b/g/n and Bluetooth are being used simultaneously, then multicast voice is not
supported.
If there is an associated client that is in power save mode, then all multicast packets will be queued until the DTIM period.
If proxy ARP from CCX is enabled and Cisco Cius is not participating in a multicast session currently, then the access point is
responsible to answer any ARP requests on behalf of the client and Cisco Cius can remain in sleep mode longer thus optimizing
battery life.
If there are many packets queued up, then they client may have to stay awake longer thus potentially reducing battery life.
With multicast, there is no guarantee that the packet will be received the by the client.
The multicast traffic will be sent at the highest mandatory / basic data rate enabled on the access point, so will want to ensure
that only the lowest enabled rate is configured as the only mandatory / basic rate.
The client will send the IGMP join request to receive that multicast stream. The client will send the IGMP leave when the
session is to be ended.
Cisco Cius supports the IGMP query feature, which can be used to reduce the amount of multicast traffic on the wireless LAN
when not necessary.
Ensure that IGMP snooping is also enabled on all switches.
It is recommended to enable Multicast Direct in the Cisco Unified Wireless LAN Controller.
Note: If using Coexistence where 802.11b/g/n and Bluetooth are being used simultaneously, then multicast voice is not
supported.
Designing the Wireless LAN
The following network design guidelines must be followed in order to accommodate for adequate coverage, call capacity and
seamless roaming for Cisco Cius.
seamless roaming for Cisco Cius.
Planning Channel Usage
Use the following guidelines to plan channel usage for these wireless environments.
5 GHz (802.11a/n)
Cisco Cius supports Dynamic Frequency Selection (DFS) and Transmit Power Control (TPC) from 802.11h, which are required
when using channels operating at 5.260 - 5.700 GHz (15 of the 24 possible channels).
DFS dynamically instructs a transmitter to switch to another channel whenever radar signal is detected. If the access point
detects radar, the radio on the access point goes on hold for at least 60 seconds while the access point passively scans for
another usable channel.
TPC allows the client and access point to exchange information, so that the client can dynamically adjust the transmit power.
The client uses only enough energy to maintain association to the access point at a given data rate. As a result, the client
contributes less to adjacent cell interference, which allows for more densely deployed, high-performance wireless LANs.
when using channels operating at 5.260 - 5.700 GHz (15 of the 24 possible channels).
DFS dynamically instructs a transmitter to switch to another channel whenever radar signal is detected. If the access point
detects radar, the radio on the access point goes on hold for at least 60 seconds while the access point passively scans for
another usable channel.
TPC allows the client and access point to exchange information, so that the client can dynamically adjust the transmit power.
The client uses only enough energy to maintain association to the access point at a given data rate. As a result, the client
contributes less to adjacent cell interference, which allows for more densely deployed, high-performance wireless LANs.