nanog mailing list archives
Re: Questions about Internet Packet Losses
From: Vern Paxson <vern () ee lbl gov>
Date: Tue, 14 Jan 1997 01:55:19 PST
Isn't it unsurpsrising that >40% of packets are small? ACKs? If one made the gross oversimplifying approximation that everything is unidirectional TCP traffic, then you'd expect to see one ACK per two data packets.
This is actually not at all a gross oversimplying approximation. Much TCP traffic unidirectional or request/response. The latter looks a whole lot like two back-to-back unidirectional connections, with only one chance to piggyback acks at the switchover.
Thus, we'd expect to see 33% at 40 bytes. It is the additional 7+% that's surprising.
Throw in frequent SYN/FIN/RST's because of small Web connections, SYN retransmissions because busy Web servers have full listen queues (or are being SYN-flooded :-), TCP's that ack every packet (Linux 1.0, I believe, and maybe later ones), TCP's that wind up acking every packet because their delay timer is less than an MSS prop time across a slow link (Solaris, for links < 10KB/sec), and dup acks due to sequence holes, and you might handwave the 7%. Vern - - - - - - - - - - - - - - - - -
Current thread:
- Re: Questions about Internet Packet Losses, (continued)
- Re: Questions about Internet Packet Losses Vern Paxson (Jan 13)
- Re: Questions about Internet Packet Losses Tony Li (Jan 13)
- Re: Questions about Internet Packet Losses Howard C. Berkowitz (Jan 14)
- Re: Questions about Internet Packet Losses Tony Li (Jan 14)
- Re: Questions about Internet Packet Losses Tony Li (Jan 13)
- Re: Questions about Internet Packet Losses Vern Paxson (Jan 13)
- Re: Questions about Internet Packet Losses William Allen Simpson (Jan 13)
- Re: Questions about Internet Packet Losses Hank Nussbacher (Jan 13)
- Re: Questions about Internet Packet Losses Barry Shein (Jan 15)
- Re: Questions about Internet Packet Losses Craig Nordin (Jan 15)
- Re: Questions about Internet Packet Losses Vern Paxson (Jan 13)
- Re: Questions about Internet Packet Losses John Hawkinson (Jan 14)
- Re: Questions about Internet Packet Losses Vern Paxson (Jan 14)
- Re: Questions about Internet Packet Losses Tony Li (Jan 14)
- RE: Questions about Internet Packet Losses Peter Cole (Jan 14)
- Re: Questions about Internet Packet Losses William Allen Simpson (Jan 14)
- RE: Questions about Internet Packet Losses Peter Cole (Jan 14)
- Re: Questions about Internet Packet Losses Kent W. England (Jan 14)
- Re: Questions about Internet Packet Losses Sean Donelan (Jan 15)
- RE: Questions about Internet Packet Losses Chris A. Icide (Jan 15)
- RE: Questions about Internet Packet Losses Barry Shein (Jan 15)
- Re: Questions about Internet Packet Losses Barry Shein (Jan 15)
- Re: Questions about Internet Packet Losses Matt Ranney (Jan 16)