OpenWrt Forum Archive

Topic: Serious problem with Video Streaming over Multicast in WLAN (OpenWRT)

The content of this topic has been archived on 3 May 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.

Hi,
I am trying to run a video multicast scenario with VLC in a wireless LAN by using OpenWRT firmware. The VLC server and client are in the same subnet and both of them are connected to the Wireless Router (with openWRT firmware).
I prepared openWRT image file for Compex board (openwrt-ar71xx-wp543-squashfs-8M-factory.img) and programmed it to use openWRT image.
After configuring the hostapd and dhcp in openWRT, client and server will connect to WLAN network.
Every time I play a Unicast video stream by means of VLC server, the client can receive the video stream properly and the quality of received video/audio from VLC server is acceptable. But, anytime I try to play a Multicast video stream by using VLC server, the quality of received video/audio in client side is awful and in most of cases I can't see any clear video and sound sad
It 's obvious that there is something wrong in most of Linux distributions to pass video multicast traffic in wireless networks even when the sender and receiver are in the same subnet. I added the multicast route in the openWRT routing table and also checked some multicast parameters in kernel config, but still this issue is unresolved!
I spent too much time to search over google and openWRT forums but no explicit solution has been suggested for this issue.
I would like to know is there any one here that has successful experience to rectify this problem?
Thanks for your attention

Regards,
Dawood

What you experience is an inherent problem with any kinds of multicast traffic on 802.11 networks.
Without further configuration, all multicast traffic is sent with 1Mbps or 6Mbps (in G only networks) data rates.

In my case, the speed is not problem. I am using 802.11g and there is enough bandwidth among access point, server and client to send and receive multicast video stream,  but in addition to mentioned problem in my 1st post, there is a tangible delay between server and client to receive multicast video stream.
I am looking for this further configuration that you mentioned...
Could you find any solution for it?

(Last edited by Dawood on 4 Jan 2012, 05:09)

No answer !

Thanks fyi for your notice
But the mentioned links are not useful for my case!
the offered solution in links are based on igmpproxy and this package works for multicast forwarding among different subnets not within a subnet, So I need to find to a solution to receive the video multicast traffic from one user through wireless interface and send it to the other wireless users in the same subnet sad
Do you checked it before?

I checked these links but their solution is useful when you are trying to forward multicasr from one subnet to another subnet, but in my case, 2 clients are placed in the same subnet!!!
igmpproxy and udpxy could't solve this problem sad

So changing "mcast_rate" doesn't work at all?

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