4.2
The Input Queueing Family
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4.2.1 The Input Queueing Family
4.2.2
Old-Style (Single-Queue) Input Queueing -
Head-of-Line Blocking
Throughput and Delay under Input Queueing
with Head-of-Line (HOL) Blocking:
When the incoming traffic consists of fixed-size packets
from independent, identically distributed (i.i.d.) Bernoulli processes,
with uniformly-distributed destination (output) ports,
analysis and simulation have yielded the results plotted below.
Sources (© copyright IEEE):
M. Hluchyj, M. Karol:
"Queueing in High-Performance Packet Switching",
IEEE Journal on Sel. Areas in Commun. (JSAC),
vol. 6, no. 9, Dec. 1988, pp. 1587-1597.
M. Karol, M. Hluchyj, S. Morgan:
"Input versus Output Queueing on a Space-Division Packet Switch",
IEEE Trans. on Communications,
vol. 35, no. 12, Dec. 1987, pp. 1347-1356.
J. Hui, E. Arthurs:
"A Broadband Packet Switch for Integrated Transport",
IEEE Journal on Sel. Areas in Commun. (JSAC),
vol. 5, no. 8, Oct. 1987, pp. 1264-1273.
Attention:
results derived for i.i.d. Bernoulli (non-bursty) arrivals,
with uniformly-distributed destinations (no overloaded hot-spots),
are only useful for gaining a rough, first insight
into the behavior of systems,
but are often not representative of the real behavior of systems
under real traffic!...
© copyright IEEE
Appendices for optional study:
Performance analysis transparencies
by prof. George Stamoulis, CS-534, Spring 2000 semester:
Spring 2000 sec. 4.6:
Input Queueing Throughput Analysis
Spring 2000 sec. 4.7:
Input Queueing Delay Analysis and Variants
Spring 2000 sec. 4.8:
Output Queueing Performance Analysis
4.2.3
Advanced Input Queueing (Buffering) -
Virtual Output Queues (VOQ)
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