Which Network Device to use to implement WAN QoS

clarke.jason.kit · ‎04-21-2010

Hi,

We currently terminate our WAN links (1Gb) on 6504 switches and no QoS is configured - the particular model we have is coming to EOL and we need to replace them with either new chassis and Sups or routers.

We will need to implement QoS on these devices as our links are becoming congested and we will start to run video conferencing over them. My question is - is there any benefit installing a router over a switch with regards to QoS performance? I understand that the 6504 switch will queue and schedule the traffic in hardware and remark and police on the PFC.... I am guessing that a router, e.g 7206VXR, will have to process all the traffic in software but the ease of configuration of QoS on the router is inviting.

I just need to justify the decision either way as the business thinks that a router should be used and are requesting pros and cons for each device.

Any comments are most welcome

Kind regards

Jason

frivers · ‎04-21-2010

Any layer 3 switch should be able to do robust QoS.

Collin Clark · ‎04-21-2010

Like you stated, most routers perform QoS in software whereas most switches do it in hardware. The ASR routers do it closer to hardware (http://www.cisco.com/en/US/partner/prod/collateral/routers/ps9343/solution_overview_c22-449961_ps9343_Product_Solution_Overview.html). If you use a switch like a 6500, you need to watch the line card model you use as each one has different queues features/mechanisms. Have you designed your QoS scheme? How many queues do you plan on using? I would start to lean towards the ASR, but the price tag is little steep.