Comware

 View Only
  • 1.  Voice VLAN on H3C S5500-SI

    Posted Jan 10, 2012 07:53 AM

    Hi there,

     

    is there a possibillity to change a vlan into a voice vlan?

     

    We didn't create a special voice vlan for the new IP-Phones we ordered and now we are running into quality problems on the phones when somebody is talking and copying something on the network..

     

    If we are not able to change the vlan, would it be enough to create a QoS Policy?

    Is anybody able to help me with that Policy, too?

     

    Regards,

    Mark



  • 2.  RE: Voice VLAN on H3C S5500-SI

    Posted Feb 03, 2012 12:07 AM
    imho, QoS is for routing priority, VLAN separates ethernet segment into broadcast domains (for example, prevent someone with itunes running on a laptop which is continually scanning for itunes shares from hosing your phone calls)

    Are the phones already on a separate VLAN?


  • 3.  RE: Voice VLAN on H3C S5500-SI

    Posted Feb 08, 2012 01:49 PM

    QOS is much more than routing priority - on switches its inbound and outbound queuing, shaping, policing, remarking, etc... 

     

    Apply the following configuration on all your ports on the switch and let me know how that helps. Trafic marked as DSCP40 to 46 will be using queue 5 and get strict priority over all other queues. We use GTS to limit the SP queue to 10Mbps to ensure an incident with marked trafic does not kill the rest of your trafic. That CIR is enough for access or uplinks on a given 48 ports, but you would obviously want to adjust it higher if you have a thousand users behind a given interface.

     

    qos wrr
    qos wrr 5 group sp
    qos gts queue 5 cir 9984
    qos trust dscp

     

    If you can confirm that your telephony solution marks its RTP voice payload with DSCP 40 up to 46 (it should be the later), this configuration will quite happily prioritize voice as your requirements.