[j-nsp] M10 maximum throughput

[Gregory Maxwell]

> -----Original Message-----
> A good description of the process is found at 
> http://juniper.cluepon.net/index.php/J-cell
> 
> But I disagree with the wiki text on
> http://juniper.cluepon.net/index.php/FPC_Bandwidth that 
> states 3.2 Gbps as a realistic worst case, because not all 
> packets will have sizes that are multiple of 64 bytes, which 
> is the only case that would achieve the 3.2 Gbps maximum.
> This reference 
> (http://www.nlanr.net/NA/Learn/Gm/pktsizes.html) states that 
> 40 byte packets account for 40% of the packets flowing 
> around; 40 byte packets require 16 byte paddings for each 
> J-Cell, so if all other packets would be 64 byte multiples, 
> performance would already been limited to 2.72 Gbps.
> 
> I agree that 2.5 Gbps is a safe bet here.

What PIC configuration will physically allow more than 6.1MPPSish per
FPC to physically enter the router? Think carefully and consider all
overhead and you will be enlightened.