Re: [nznog] CIR on VDSL2

On 25 May 2012 11:11, Nicholas Lee wrote:

On Fri, May 25, 2012 at 9:59 AM, Curtis Owings wrote:

...

You know... CIR

*Disclaimer* I worked on some of this stuff in one capacity or another; this is my personal opinion not that of the company I work for. This is all done with P bit (P802.1p) marking. As has been said your Sub cap (in $ doesn't matter land) is your Backhaul/Sum(CIR) for all services offered from a particular ISAM Chassis (I don't care what the last mile is it doesn't matter fiber or copper). In an ideal world this really would be the point of where you add more chassis/backhaul. Unfortunately not many rolls-outs have that sort of money to throw at it so you end up with a complex policer and scheduler system to enable the number of Subs to be pushed up independent of the bandwidth constraints. The rationale being that the maintenance and engineering overhead of maintaining the network in this state outweighs the cost of laying more fiber and buying more ports - whilst not negatively impacting the user experience.