vlan QoS priority over ports

[Anonymous]

We use Adtrans for our voip trunk/phone installs. Most of the time the customer already has a IT company and its a lot easier just for us to install a adtran to control for the phone service instead of getting the existing stuff to work, then having to deal with another company to troubleshoot or resolve issues. Sometimes I am using the same lan scope, sometimes not or sometimes a vlan depending on the size and situation. Most of the time though I need to share the WAN connection. I just take a available address and setup a vlan on the adtran, normally go threw the startup script. Then have two ports on that vlan, one from the ISP and the other to their existing router. But this is my question, there must be a way to setup the adtran so the traffic from the vlan (threw sip proxy) has priority over the customers other router plugged into the second port. For example the ISP is plugged into port 1, the customers existing router into port 2 and both ports are on vlan 10. The rest of the switch is under vlan 1 the local subnet, where the phone system and phones are. I want the SIP/RTP traffic going threw the adtran out to the ISP on port 1 to have priority over the traffic on port 2, the customers existing router. Their computers and exiting router remain as they are, I am just adding the adtran just for voice. How do I specify traffic from the adtran vlan 10 address to have priority over the traffic that is coming from port 2? Because the internet service is only like 60 down 4 up, I need to make sure my voice traffic is getting out over that 4mb uplink, even when they are maxing out their internet usage for file transfers. Thanks!

[Anonymous]

If we are talking about a 1335, there are two areas you can use to improve and prioritize the voice.

1.  CoS (Class of Service).  Make sure that the class of service queuing is enabled on the device, and set it to strict-priority if your device supports it.  Then make sure that your Voice/SIP server is configure with a CoS value of 5 or higher.  If that is not possible, you can set the default class of service on the switchport to 5 or higher.  This would be the port the Voice/SIP server is using. 

2.  QoS (Quality of Service). Configure traffic shaping on the outbound circuit and configure a QoS policy that matches the RTP traffic or IP address of the SIP server.  In my installations, I configure the SIP server to tag packets with DSCP values, but you can match access-list or RTP.

Example:

qos map RTP 10

  match RTP range 10000 10500 all (whatever the range of RTP ports is for your configuration).  "all" means even and odd port numbers.

  priority unlimited

  set precedence 5

interface vlan 100  (whatever your outbound IP interface is )

ip address x.x.x.x y.y.y.y

access-policy Public

traffic-shape rate 4M

qos-policy out RTP

no shutdown

This should match all RTP packets and give them priority over normal data packets.  NetVanta routers can only control outbound traffic, If this is an internet connection, then it's best effort anyway. 

I hope this helps.

[Anonymous]

That I understand if the traffic goes threw the adtran firewall and the source is the vlan address, but does this apply to the connection to the other router the customer has plugged into port 2 using a different WAN address so that traffic does not go threw the vlan 10 interface? Basically I need the traffic  from the vlan 10 address to take priority over the traffic on port 2, or in other words the customers existing router on the same subnet on the WAN interface? Thanks!