Latency, TCP ACKs and upload needs
dot at dotat.at
Wed Apr 20 16:12:36 UTC 2016
Leo Bicknell <bicknell at ufp.org> wrote:
> 1460 byte payloads down, maybe 64 byte acks on the return, and with SACK
> which is widely deployed an ACK every 2-4 packets. You would see about
> 2,140 packets/sec downstream (25Mbps/1460), and perhaps send 1070 ACKs
> back upstream, at 64 bytes each, or about 68Kbps. Well under the 1Mbps
> upstream bandwidth.
Note that with delayed ACKs (RFC 1122) there is an ACK for every other
packet; SACK should do better than that.
f.anthony.n.finch <dot at dotat.at> http://dotat.at/ - I xn--zr8h punycode
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