diff options
| author | Jeremy Harris <jgh146exb@wizmail.org> | 2016-10-21 00:26:14 +0100 |
|---|---|---|
| committer | Jeremy Harris <jgh146exb@wizmail.org> | 2016-10-22 22:18:17 +0100 |
| commit | fb05276aaee4c27b6f20fb1f32290ee40a929064 (patch) | |
| tree | f108448c1499972f896bf9acd891908799481d09 /doc/doc-docbook | |
| parent | cfda83c6d64b5af00ef5f7a20bcc0dd58e489ef4 (diff) | |
TCP Fast Open
Diffstat (limited to 'doc/doc-docbook')
| -rw-r--r-- | doc/doc-docbook/spec.xfpt | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt index 45d845718..478b5e1a4 100644 --- a/doc/doc-docbook/spec.xfpt +++ b/doc/doc-docbook/spec.xfpt @@ -23986,11 +23986,30 @@ unauthenticated. See also &%hosts_require_auth%&, and chapter .cindex CHUNKING "enabling, in client" .cindex BDAT "SMTP command" .cindex "RFC 3030" "CHUNKING" -This option provides a list of server to which, provided they announce +This option provides a list of servers to which, provided they announce CHUNKING support, Exim will attempt to use BDAT commands rather than DATA. BDAT will not be used in conjuction with a transport filter. .wen +.new +.option hosts_try_fastopen smtp "host list!!" unset +.option "fast open, TCP" "enabling, in client" +.option "TCP Fast Open" "enabling, in client" +.option "RFC 7413" "TCP Fast Open" +This option provides a list of servers to which, provided +the facility is supported by this system, Exim will attempt to +perform a TCP Fast Open. +No data is sent on the SYN segment but, if the remote server also +supports the facility, it can send its SMTP banner immediately after +the SYN,ACK segment. This can save up to one round-trip time. + +The facility is only active for previously-contacted servers, +as the initiator must present a cookie in the SYN segment. + +On (at least some) current Linux distributions the facility must be enabled +in the kernel by the sysadmin before the support is usable. +.wen + .option hosts_try_prdr smtp "host list&!!" * .cindex "PRDR" "enabling, optional in client" This option provides a list of servers to which, provided they announce |