Description: 
This module contains definitions for performance monitoring of the
ATM cell layers.

This MIB module contains the following tables:

  ATM Cell Layer 15 Minute Current Table (per interface)
  ATM Cell Layer 15 Minute History Table (per interface)
  ATM Cell Layer 24 Hour Table (per interface)
  ATM Cell Layer Raw Table (per interface; unintervalized)
 
Intervals:
        Statistics per interface are collected over a historical stratum of
  up to a maximum of M intervals. The value of M is a function of a
  product's storage capability. For example, on the 36170 product, 
  M = 96.  

  The intervals are 15 minutes aligned to the quarter of an 
  hour.  The current interval spans back to the last 15 minute tick on
  the wall clock. Continuing along the timeline from that point is the
  most recently completed interval and has an index of 1. The previous
  interval has an index of 2 and so on. Note that the oldest interval
        may be incomplete since the statistic collection may have been
        enabled offset to the quarter or one hour tick.

               t
               0          -15min    -30min      -45min
       ==========|===========|===========|===========|===========
        current      N = 1       N = 2       N = 3       N = 4    ... N = M
        interval