ACM Discussion – BufferBloat: What’s Wrong with the Internet? #bufferbloat @ACMQueue

ACMIn an ACM discussion BufferBloat: What’s Wrong with the Internet? (pdf) TCP experts Vint Cerf, Van Jacobson, Nick Weaver, and Jim Gettys discuss the growing problem of clogged networks.

From the preamble:

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.