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Cisco switch/router - prioritizing voice traffic

I have a small office with one VLAN.  There are 15 IP phones and 15 PC's that plug into a Cisco 3560G switch.  The phones and PC's are on the same VLAN.  The phones are provided via a hosted VOIP provider.  Lately we have been experience voice quality issues.  The hosted VOIP provider have asked us to prioritize the voice traffic so it has priority over all other traffic out to the WAN.  My network is very simple and looks as follows:

Cable Modem----------Cisco 2911 Router-----------Cisco 3560G switch (phones and PC's plug into this switch.)

Could someone please send me a sample config on how to accomplish this?  Thank You!
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1 Solution
Hemil AquinoNetwork EngineerCommented:
You'd need two vlans on the switch and two sub interface on the router.

Router conf

encapsulation dot1.q
ip address of your local network:
ip nat inside

Fa0/0.2  --vlan 2 for the phone
encapsulation dot1.q
ip address -- Ip address for you phone
ip nat inside

Switch conf:

Since you have vlan 1 working.
Create a second vlan. Vlan 2
you can give an ip address if you want.

Then swithcport your interface. Ex: interface fa0/1

switchport access vlan 1
Switchport voice vlan 2
Switchport mode access
auto qos voip  cisco-phone
denver218Author Commented:
Hello.  Right now everything is on the same vlan.  PC's do not plug into phones, both PC's and phone have their own connection to the switch.  what can i do in this scenario?
Hemil AquinoNetwork EngineerCommented:
I dont know what type of SIP phones you have but I'm sure you should see two ports on the back of the phone.

One for a computer
One for a phone

From the switch connect it to the phone and from the phone to the computer.
Or if you want to use different connection you can use different connection from your switch.

Like one connection for your phone and another connection for your computer.
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denver218Author Commented:
This is a remote office.  The PC's do not plug into the phones.  The phone plug directly to the switch and the PC's plug directly to the switch.  What can I do in this scenario?
Hemil AquinoNetwork EngineerCommented:
from the switch get a cable to the phone.
On the switch side give a switchport access vlan 2

That way every Port will have different vlan traffic
Also make sure you execute the command
Auto QoS VoiP
Havin a layer 2 switch, your switch related qos requires that you manually assign ports to which phones connect to be in the voice VLAn, the qos on the router could be configured based on the data type 5260 destination/src higher priority while http/https/FTP/SMTP is lower.
Allocated a dedicated portion of the bandwidth to voice..

Cisco.com has several descriptions, examples of qos on the 2911....
denver218Author Commented:
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