Exam 20: Congestion Control

Fairness,QoS,and reservations are all issues related to congestion control that fall into the category of __________ .

_________ schemes are common for end-to-end flow control,in which a destination system uses credit to prevent the source from overflowing the destination buffers.

The TCP congestion control measure techniques fall into two categories: retransmission timer management and ________ management.

_________ explicit congestion signaling approaches notify the user that congestion avoidance procedures should be initiated where applicable for traffic in the same direction as the received notification.

Token bucket is used in the Bluetooth specification.

A ________ fills at a constant rate up to the capacity of the bucket and empties at a rate dictated by the input data stream while the bucket is not empty.

Congestion control on the basis of implicit signaling requires action on the part of network nodes.

A _________ empties at a constant rate while the bucket is not empty and fills at a rate dictated by the input stream up to the capacity of the bucket.

Congestion control is concerned with efficient use of a network at high load.

A common technique for predicting the next value on the basis of a time series of past values,and the one specified in RFC 793,is _________.

Typically,_______ congestion control techniques operate over connection-oriented networks and control the flow of packets over individual connections.

If the rate at which packets arrive and queue up exceeds the rate at which packets can be transmitted,the queue size grows without bound and the delay experienced by a packet goes to infinity.

A _______ is a control packet generated at a congested node and transmitted back to a source node to restrict traffic flow.

An example of a choke packet is the ICMP Source Quench packet.

Even if all sources can detect congestion and reduce flow on the basis of congestion,network congestion still will not be relieved.

For ________ congestion avoidance,the network alerts end systems to growing congestion within the network and the end systems take steps to reduce the offered load to the network.

In a rate based scheme any node along the path of the connection can reduce the data rate limit in a control message to the source.

__________ proposed two procedures,called fast retransmit and fast recovery,that under some circumstances improve on the performance provided by RTO.

Defined in RFC 4340,__________ is an unreliable connection-oriented protocol that can include mechanisms for detecting congestion by determining round-trip time and packet drop rates.

The size of TCP's send window can have a critical effect on whether TCP can be used efficiently without causing congestion.