This attribute specifies the maximum frame size in bits that can be
transmitted or received. This value must be greater than or equal to
the maximum packet size across the interface(in bits)+ max level 3
header size(in bits)+ max level 2 header size(in bits)+ crc in bits.
(max Pkt size + -------------> 4096*8
max level 3 header size + ---> 4*8
level 2 header size + --------> 5*8
crc -------------------> 2*8)