  Knowledge about which nodes provide services is of critical importance for
network administrators. Discovery of service nodes can be done by making full
use of duplicate element detection in flows. Because the amount of traffic
across network is massive, especially in large ISPs or campus networks, we
propose an approximate algorithm with Round-robin Buddy Bloom Filters(RBBF) for
service detection using NetFlow data solely. The properties and analysis of
RBBF data structure are also given. Our method has better time/space efficiency
than conventional algorithm with a small false positive rate.%portion of false
positive. We also demonstrate the contributions through a prototype system by
real world case studies.
