4-way pure telephone optical end machine (pair) 4-way telephone optical end machine plus 1 100M network (pair) 4-way telephone optical end machine plus 2 100M Network(pair) 4-way telephone optical end machine plus 2 100M Network (pair) 4-way telephone optical end machine plus 2 100M Network (pair) 4-way telephone optical end machine plus 2 100M Network (pair)