A distributed fabric system comprises a plurality of independent network elements interconnected by inter-switch links and assigned to a same group. Each network element includes one or more switching chips, a processor, and memory storing program code that is executed by the processor. The program code of each network element includes a switch discovery protocol (SDP) module. The SDP module of each network element, when executed, periodically multicasts SDP data units (SDPDUs) using one of a plurality of transmission rates. The plurality of transmission rates includes a fast transmission rate and a slow transmission rate. The transmission rate used by the SDP module of each network element is the fast transmission rate until the SDP module of that network element determines a criterion is met, in response to which the transmission rate used by the SDP module of that network element changes to the slow transmission rate.