...so that all the subclasses have such attributes. This
allows queue discs to have attributes specifying the mode and
size of their queue(s) and to create queues using their
own attributes.
This commit is heavily inspired by Natale's queue rework patch:
https://codereview.appspot.com/270540044/
This patch adds a NetDeviceQueue class to store information about a single
transmission queue of a network device. This class is meant to store the
state of a transmission queue (i.e., whether the queue is stopped or not)
and some data used by techniques such as Byte Queue Limits. Also, multi-queue
aware queue discs can aggregate a child queue disc to an object of this class.
These features (excluding BQL) are added in subsequent commits.
The NetDevice class maintains a vector of NetDeviceQueue pointers, one for
each transmission queue. A NetDevice constructor is added which creates a
single transmission queue by default for every device. The number of transmission
queues can be modified (by child classes) by calling NetDevice::SetTxQueuesN.
Two public methods, GetTxQueue and GetTxQueuesN, are also added to the NetDevice class
to return the i-th NetDeviceQueue and the number of transmission queues, respectively.
A QueueItem base class is introduced to represent the items stored
in a Queue. The base class only contains a Ptr<Packet>. Derived classes
can store additional information. DropTailQueue, RedQueue and CodelQueue,
along with their examples and testsuits, have been adapted. Objects using
such queues have been adapted too.
TcpNewReno is introduced in RFC 2582. The most recent RFC on this is
the RFC 6582. Since its introduction, Tcp NewReno is the RECOMMENDED
algorithm by the Internet Engineering Task Force. The main difference
between Reno and New Reno is in the Fast retransmit algorithm, in order
to recover more quickly when multiple packet losses occur in a single
window. NewReno introduces the concept of Partial acknowledgments. Since
the intention is to merge fast retransmit and fast recovery into
TcpSocketBase, there isn't the possibility to maintain TcpReno as
separate class. However, its behavior could be introduced again with one
conditional attribute in TcpSocketBase itself.
Move from template class TracedValue to namespace TracedValueCallback.
Rename from [type]Callback to just [type]:
TracedValue<double>::DoubleCallback -> TracedValueCallback::Double
