[ih] BufferBloat: What's Wrong with the Internet?

[the keyboard of geoff goodfellow]

*A discussion with Vint Cerf, Van Jacobson, Nick Weaver, and Jim Gettys*

December 7, 2011
Volume 9, issue 12

Note: Be sure to read the companion article to this one, Bufferbloat: Dark
Buffers in the Internet <https://dl.acm.org/detail.cfm?id=2071893> (
https://cacm.acm.org/magazines/2012/1/144810-bufferbloat/fulltext)*. - Ed.*

*Internet delays are now as common as they are maddening. That means they
end up affecting system engineers just like all the rest of us. And when
system engineers get irritated, they often go looking for what's at the
root of the problem. Take Jim Gettys, for example. His slow home network
had repeatedly proved to be the source of considerable frustration, so he
set out to determine what was wrong, and he even coined a term for what he
found: bufferbloat.*

*Bufferbloat refers to excess buffering inside a network, resulting in high
latency and reduced throughput. Some buffering is needed; it provides space
to queue packets waiting for transmission, thus minimizing data loss. In
the past, the high cost of memory kept buffers fairly small, so they filled
quickly and packets began to drop shortly after the link became saturated,
signaling to the communications protocol the presence of congestion and
thus the need for compensating adjustments.*

*Because memory now is significantly cheaper than it used to be, buffering
has been overdone in all manner of network devices, without consideration
for the consequences. Manufacturers have reflexively acted to prevent any
and all packet loss and, by doing so, have inadvertently defeated a
critical TCP congestion-detection mechanism, with the result being worsened
congestion and increased latency.*

*Now that the problem has been diagnosed, people are working feverishly to
fix it. This case study considers the extent of the bufferbloat problem and
its potential implications. Working to steer the discussion is Vint Cerf,
popularly known as one of the "fathers of the Internet." As the co-designer
of the TCP/IP protocols, Cerf did indeed play a key role in developing the
Internet and related packet data and security technologies while at
Stanford University from 1972-1976 and with DARPA (the U.S. Department of
Defense's Advanced Research Projects Agency) from 1976-1982. He currently
serves as Google's chief Internet evangelist.*

*Van Jacobson, presently a research fellow at PARC where he leads the
networking research program, is also central to this discussion. Considered
one of the world's leading authorities on TCP, he helped develop the RED
(random early detection) queue management algorithm that has been widely
credited with allowing the Internet to grow and meet ever-increasing
throughput demands over the years. Prior to joining PARC, Jacobson was a
chief scientist at Cisco Systems and later at Packet Design Networks.*

*Also participating is Nick Weaver, a researcher at ICSI (International
Computer Science Institute in Berkeley where he was part of the team that
developed Netalyzr, a tool that analyzes network connections and has been
instrumental in detecting bufferbloat and measuring its impact across the
Internet.*

*Rounding out the discussion is Gettys, who edited the HTTP/1.1
specification and was a co-designer of the X Window System. He now is a
member of the technical staff at Alcatel-Lucent Bell Labs, where he focuses
on systems design and engineering, protocol design, and free software
development...*

[...]

https://queue.acm.org/detail.cfm?id=2076798

also at

https://cacm.acm.org/magazines/2012/2/145415-bufferbloat-whats-wrong-with-the-internet/fulltext

-- 
Geoff.Goodfellow at iconia.com
living as The Truth is True