Multicast Filtering

Background

Whilst Songcasting in large-scale mode, Linn DS players generate significant amounts of Multicast traffic on the network. Many consumer grade network switches, including many all-in-one router/switch/WAP units will broadcast this Multicast traffic to ALL devices on the network, rather than just those which have requested it.

Problem

This Multicast traffic may cause the WAP to be overloaded

• wireless network malfunctions and becomes unreliable
• unable to connect to the wireless network.

Solution

• All DS players which are participating large-scale Songcast must use wired network paths between themselves.
• The network traffic must be filtered to ensure that Multicast traffic is not sent over the wireless network.
  • This uses a process known as IGMP snooping

IGMP Snooping

This is a feature of network equipment, and may require an upgrade to the network infrastructure to operate successfully and prevent wireless network issues

WAP (or all-in-one box)

• Enable IGMP snooping in the options

Managed Switch

• Enable IGMP snooping in the options
• Ensure network path between DS players and WAP go through the switch

Tested Devices

The following devices have been tested and shown to work. Note that the hardware and firmware of these devices is under the control of their respective manufacturers and may change from what was tested

• WAP
  • Dlink DWL3200AP (Firmare 2.55 or later)
  • Ubiquitu UniFi (Firmware 2.2.5.1080)
• All-in-one
  • Buffalo WHR-G300N AirStation (Firmware V1.82/1.85)
  • ZyXEL NBG-417N
  • ZyXEL NBG-4615 (Fimware 1.00(BWQ.2)C0 )
  • Billion BiPAC 6200 NXL
  • DLINK DIR-655/B (Firmware 2.00 , 12, Aug, 2010)
    • (Advanced - Enable Multicast Streams)
• Managed Switch
  • Cisco (Linksys) SLM2008
  • Cisco SG300-10 [http://docs.linn.co.uk/wiki/images/e/ef/Cisco_SG300_IGMP_setup.pdf Setup

example]

• • ZyXEL ES-2108
  • ZyXEL GS2200
  • HP Procurve 2510-24G (J9279A)

• Apple AirPort Extreme was tested and does NOT work

Customer/Retailer device reports

This information is supplied to Linn Products by Retailers/Customer. Linn Products has not tested any of these devices

• Fritzbox reported having issues with Apple broadcasts and losing connections. This appear to be due to the Fritzbox monitoring the LAN sockets and shutting down anything that is not active and going into Green (power saving) mode.

The manufacturer has reported the following fix:

1. Open a web browser and enter "fritz.box" into the address bar to open the router's
   configuration page
2. Go in to advanced/expert mode, rather than Wizard mode
3. Go to the "System > Energy Monitor > Settings" pane
4. Set the LAN port that the DS is plugged into to be "always active"
5. Click the "Apply" button