These two boards have no difference physically. In fact they are one board �SPE1, with the same screen-printing.
They are named differently only for the NMS to manage such boards.
SEP1: A processing board with 2*155M electrical interfaces. It cannot support an interface board or TPS.
SEP: An SEP processing board must be connected to an interface board (otherwise no ports are available on the board). An SEP electrical board supports TPS, but does not support protection between the electrical interface boards with a different number of ports.
Board software is identified through the interface board type configured by users. When a configured interface board type is found inconsistent with the current interface board type, the board type will be re-confirmed after hard resetting of the board.
Note: When a board is SEP both physically and logically, only deleting the logical interface board will not cause the board to reset, with its logical and physical types keeping unchanged. This makes convenience for users to replace or upgrade the interface board.