System for determining individual cell/pocket loss in ATM/IP networks among on-off sources

DETAILED DESCRIPTION A system is therefore needed which can project the performance metrics for each individual connection based on the measurement at the switch aggregate level.
By assuming the incoming traffic is conforming to its declared traffic descriptors (i.
e.
, leaky bucket parameters), information such as the peak cell rate (PCR), sustainable cell rate (SCR), and burst tolerance can be collected from each connection.
Based on the measurement on cell loss ratio (CLR) at the aggregate level, an estimate for the CLR for each individual connection can be obtained.
If the aggregated cell loss at port level are obtained through measurements and it is assumed that all of the sources have conforming traffic characteristics (usually based on leaky buckets parameters), then the individual cell loss for each connection can effectively be determined.
This is particularly true if it is assumed that the connections generate heterogeneous on-off traffic with a given peak rate, mean active, and idle periods.
The present invention includes a system for determining cell loss among on-off sources on a network by determining aggregate cell loss of the sources; determining mean rate of each of the sources; determining burstiness of each of the sources; determining average burst length of each of the sources; determining buffer size; and approximating the cell loss ratio of each of the sources based substantially only upon the aggregate cell loss, the mean rate, the burstiness, and the average burst length.
This approximation can be calculated using the formula: ##EQU3## where .
gamma.
.
sub.
i is the individual cell loss ratio, .
gamma.
is the aggregate cell loss ratio, r.
sub.
j is the mean rate, and A is computed from the formula: ##EQU4## where T.
sub.
i is the average burst length of each of the sources, B.
sub.
i is the burstiness, and B is the buffer size.