The type of queuing used in the Hold Queue.
First In First Out Queuing implies that the interface always
transmits messages in the order that they are received.
Priority Queuing sorts messages out by the use of access lists.
Messages in a higher priority queue are always sent in
preference to messages in a lower priority queue.
Custom Queuing sorts messages out by the use of access lists.
Sub-queues are selected in round robin order as either the
sub-queue is drained or a given number of octets is moved from
the sub-queue to the transmission queue.
Weighted Fair Queuing sorts messages by 'conversation', which
is source-destination pair of addresses and sockets or ports,
as defined by the network layer protocol. Messages are removed
from queues in a sequence that gives each conversation a
proportion of the available bandwidth.