CH A P T E R
IP Multicast in a Wireless LAN
This chapter describes the configurations needed to control IP Multicast traffic over a Wireless LAN (WLAN) and includes the following sections:
Multicast WLAN Deployment Recommendations IP Multicast WLAN Configuration Other Considerations Summary
For information about wireless theory, deployment, and configuration, please see the Cisco AVVID Wireless LAN Design SRND.
This chapter uses MoH and IP/TV in the examples. It does not, however, provide detailed configurations and designs for MoH and IP/TV. A basic MoH and IP/TV implementation is covered in Chapter 7, “Multicast Music-on-Hold and IP/TV Configurations.”
Also, other types of IP multicast implementations, such as IP multicast for financial deployments, are not covered.
Multicast WLAN Deployment Recommendations
By default, IP multicast traffic is permitted to stream across a WLAN. However, because WLANs use shared bandwidth, certain measures should be taken to prevent saturation of the available bandwidth. If IP multicast traffic is not required on the wireless network, it is recommended that a boundary be configured to block the multicast traffic. The best place to control IP Multicast traffic is on the routers and switches that connect to the wireless Access Points (AP) and bridges. If a Layer 3 device is not available for use in deploying the configurations described in this chapter, then see the Cisco AVVID Network Infrastructure Wireless LAN Design SRND for recommendations for using AP and bridge MAC and IP filters to block traffic.
Filters on the AP and bridge do not provide the flexibility needed for true multicast control.
Cisco AVVID Network Infrastructure IP Multicast Design