Switch Board
From Juniper Clue
"Switch Board" is a generic Juniper term to refer to the pluggable board involved in traffic transport at any level.
Different generations of Juniper products use the term differently:
M-series products are using the more specific term S-Board to refer to a board with L3 lookup processing.
T-series products are using a term SIB to refer to the fabric planes. Packet processing itself is done on the linecards.
MX-series products use SCB term to refer to integrated fabric/RE carrier card. Packet processing itself is done on the linecards.