Browse Prior Art Database

Use of Queueing Delay for Data Transmission Flow Control

IP.com Disclosure Number: IPCOM000116278D
Original Publication Date: 1995-Aug-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 2 page(s) / 64K

Publishing Venue

IBM

Related People

Esteve, D: AUTHOR [+4]

Abstract

Disclosed is an algorithm used for flow control. This algorithm is based on the delay introduced when queues build up in a network node.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Use of Queueing Delay for Data Transmission Flow Control

      Disclosed is an algorithm used for flow control.  This
algorithm is  based on the delay introduced when queues build up in a
network node.

      As the cost of memory drops, there is almost endless storage to
keep transiting data in  an intermediate network node; in
consequence, this transiting data may stay in the network node for a
too long time.  As these  data are not delivered in time to the
receiving end user, the end user recovery mechanism takes place.
Then, it does not worth it for a too congested transport network to
deliver too old data that are being recovered by the end users.

In a transit network node, the queues build up in the two following
circumstances:
  1.  The processor(s) is(are) not powerful enough to process all the
       data that are entering the node.
  2.  There is more data to send on a line than the bandwidth of this
       line permits.

      Up to now, the memory size was used as a gauge to decide when
the system was entering in congestion.  As the cost of the memory
decreases, the memory size is no more the gating factor.  Therefore,
the sizes of the queues where the data are lagging may increase, and
this introduces additional delays.

      These additional delays being repeated in all the intermediate
nodes may introduce an overall transit delay that is in the same
range as the layer 2 acknowledgment timer value.  When the transit
delay reaches or exceed the acknowledgment timer, the end user will
resend the unacknowledged frame.

      When the end user recovery mechanism takes place, it...