prioritize VoIP and Skype traffic in office access router
I have a Cisco 1841(c1841-advipservicesk9-mz.124-25d.bin) router serving as a gateway in office. Fa0/0 is facing the ISP and Fa0/1 is facing the office LAN. In case somebody uploads something and at the same time there is a VoIP or Skype conversation, the quality of the voice traffic is poor. Probably there is a congestion on the LAN port. I would like to prioritize VoIP and Skype traffic. What would be the best strategy here? As I understand, options would be AutoQOS, DSCP/TOS or NBAR classification? Or should one start with NBAR protocol-discovery in order to define a QoS strategy?