QoS over ADSL link

Routing & Switching Quality of Service
1

Could anyone please show an example of QoS on ADSL link.

  1. I want to assign 15% BW for the voice over ADSL link
  2. Or if Number 1 is not possible if there is no assured BW at least how to give priority Voice traffic and apply on ADSL link.

I need it very urgently. Please respond if anyone has any idea.

2

I think it’s not possible. Because the ISP will needs mark the traffic too. The ADSL service does not mark the traffic by default. All the traffic at your edge apply de FIFO rule, even if you configure QoS

3

Thank you for your reply.
What configuration do i need to put in my ISP PE router. PE working as LNS, PPP authenticated via Radius. Cant we prioritize our voice traffic over ADSL?

CPE(ADSL)-------------ADSL Provider-------POI (ADSL Provider and ISP Interconnection)-------PE(LNS, PPP user & Pass are configured in Radius)------ISP MPLS -CLOUD (Connected to other sites of CLient)-------------Mitel Hosted Voice-server------Internet----

4

Assigning 15% of priority for VoIP traffic could be as simple as:

R1(config)#class-map VOIP
R1(config-cmap)#match protocol rtp
  
R1(config)#policy-map QOS
R1(config-pmap)#class VOIP
R1(config-pmap-c)#priority percent 15

This can be applied to an outbound interface. The problem, however, as @laislaelectronica mentioned is that this only works for your local interface. Regular (consumer) DSL connections usually treat everything as FIFO down the line. ISPs that do support QoS usually support a number of queues where you have to mark your traffic with a certain DSCP value.

The other thing with DSL is that there are a lot of different options and it depends on your router model / IOS / configuration how and where to apply QoS (eg Dialer interface, Ethernet interface, etc.).