The maximum size in bytes of a Small PPP packet.
Use of this parameter is no longer recommended.
The MP fragmentation threshold is controlled
by mpBundleStatusMediumPktMaxSize.
Small PPP packets are defined to be those which will be
encapsulated in a single Multilink Protocol Fragment
and always sent on the first link in the Bundle.
Note that this parameter only applies to outgoing PPP
packets sent by this system. Reassembly of incoming
packets is unaffected by this value.
Note that the default value of 12 bytes effectively
means that no packets are subject to this rule.