The HWIC bus interface is limited to 400 Mbps of full duplex. The actual throughput of the Gigabit Ethernet HWIC is limited by the throughput of individual platforms. Under bidirectional traffic of 1518 bytes or larger, the Gigabit Ethernet HWIC can support up to an aggregate of 350 Mbps on Cisco 2811 and 2821 routers, 400 Mbps on Cisco 2851 routers, and 500 Mbps on Cisco 3800 Series platforms.

Hey Guys,

I see this post is quite old, but I came across it while doing some thoughput tests on a Cisco 2821. I'm a little confused about the difference between the Router Performance sheet and the results I'm coming up with.

I'm currently looping my Ixia Packet generator through a bone-dry 2821 and I'm receiving about 260M througput using an HTTP test:

Portable Product Sheets – Routing Performance 
Numbers are given with 64 byte packet size, IP only, and are only an indication of raw switching performance.