Indicates whether this interface is a point-to-point interface.
If the value of this object is 'true', neighbors are not
required to send DVMRP-Hello messages. This is provided for
backward-compatibility with some older implementations that do
not send DVMRP-Hellos on point-to-point links.
Changing the value of this object while the interface is
operationally active MAY cause the interface to be deactivated
and then reactivated.