The wide-area traffic transiting the FIX now crosses an OC3 link and requires a special Coral OC3 monitoring device. Coral/OC3mon can collect summary traffic flow statistics in real-time, or collect short packet header traces for later in-depth analysis.
We have placed an OC3mon at FIX-west, which sits on one of the 4 OC-3 links between AIX (ARC) and MAE-west. Our Oc3mon is just on one of these four links, which all share traffic via the Digitial gigaswitch's load balancing techniques, which forestalls tight integrity of flow-based analysis/statistics.
In particular, when a packet arrives destined for a hunt group, it picks a hunt group member on which to attempt to transmit. If that member is busy (i.e., the crossbar is in use), it tries the next hunt group member, etc. The choice of initial hunt group member is essentially random, but not neccesarily evenly distributed. (@@so far as we could tell from the engineers we asked.) Definitely not round-robin or per flow or anything predictable. ...