SMC Networks EZ Connect SMC2662W User Manual page 25

D I
RIVER NSTALLATION
12. "Preamble Type" offers a dropdown list with three options:
Auto, Long, or Short. (see "Terminology" on page 49 for an
explanation of "Preamble Type") If you aren't sure whether all
the Clients and Access Point radios in your wireless network
support the Short RF preamble, then leave this setting on
"Long." (Default)
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