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Reduce TCP_MINMSS default to 216. The AX.25 protocol (packet radio)

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is frequently used with an MTU of 256 because of slow speeds and a
high packet loss rate.
This commit is contained in:
Andre Oppermann 2004-01-09 14:14:10 +00:00
parent c849849d06
commit 1ddc17c1d5
1 changed files with 3 additions and 4 deletions
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7
sys/netinet/tcp.h
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@ -111,15 +111,14 @@ struct tcphdr {
*/
#define TCP_MSS 512
/*
* TCP_MINMSS is defined to be 256 which is fine for the smallest
* link MTU (296 bytes, SLIP interface) in the Internet.
* TCP_MINMSS is defined to be 216 which is fine for the smallest
* link MTU (256 bytes, AX.25 packet radio) in the Internet.
* However it is very unlikely to come across such low MTU interfaces
* these days (anno dato 2003).
* Probably it can be set to 512 without ill effects. But we play safe.
* See tcp_subr.c tcp_minmss SYSCTL declaration for more comments.
* Setting this to "0" disables the minmss check.
*/
#define TCP_MINMSS 256
#define TCP_MINMSS 216
/*
* TCP_MINMSSOVERLOAD is defined to be 1000 which should cover any type
* of interactive TCP session.