prefix aggregation


  In many places yet we're discussing prefix aggregation for at least
  193/8, 194/8 and 195/8 IP blocks.

  I was told since a while that some US carriers -such as SprintLink-
  have decided to filter (id. no more route) prefixes longer than /19.

  My questions is :

    - is this impleted yet ?
    - if yes, who does it, for which class(es) of prefixes of which length ?
    - if no, when do you intend to have this filtering operational ?

  As I'm acting as a "consultant" for the french academic network (Renater)
  I'm interesting in knowing what policy every ISP -specially in the US
  of A- intend to implement in the near future.

  Thanks for your help and time,


  +Bernard Tuy.