Bridged connections in hardware, measured on the XGS 3300 and the XGS 136, 2026-10-24
Discovery 9 of the discoveries, taken from the
source to a product - and a fault found on the way (723).
A connection a bridge carries - two machines on two ports of one bridge, talking to each other - was
made into a flow as if the appliance routed it: its next hop came from the routing table, and the
microflows rewrote both MACs and lowered the TTL. On the XGS 3300 that sent such a connection's
frames out of the WAN port when the bridge had no address, and rewrote every frame when it had one;
on the XGS 136 it was not made at all, and the host's bridge carried every frame. Both drivers now
make it a bridged flow: each direction leaves by the port the other direction comes in on, and the
fast path's bridge control rewrites nothing (USFP_BRCTL_*: OCTEP_BRCTL_BRIDGED,
NPURPC_BRCTL_BRIDGED, where routed connections keep ..._ROUTED).
The whole page, with how it was taken and what it does not show: Bridged connections in hardware, measured on the XGS 3300 and the XGS 136, 2026-10-24.
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