This object specifies the adjustment to the Maximum Segment
Size (MSS) of TCP SYN packets received by the target interface
contained in IPv4 datagrams.
The value '0' cannot be written to an instance of this object.
However, it serves as a convenient value when the column is not
valid.
This column is valid only if the 'ipv4TcpMssAdjust' bit of the
corresponding instance of cdtIfValid is '1'.