tcp: implement RFC 5961 3.2

[pandora-kernel.git] / Documentation / networking / ip-sysctl.txt

diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index f049a1c..3b979c6 100644 (file)
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -137,7 +137,7 @@ tcp_adv_win_scale - INTEGER
        (if tcp_adv_win_scale > 0) or bytes-bytes/2^(-tcp_adv_win_scale),
        if it is <= 0.
        Possible values are [-31, 31], inclusive.
-       Default: 2
+       Default: 1
 
 tcp_allowed_congestion_control - STRING
        Show/set the congestion control choices available to non-privileged
@@ -282,11 +282,11 @@ tcp_max_ssthresh - INTEGER
        Default: 0 (off)
 
 tcp_max_syn_backlog - INTEGER
-       Maximal number of remembered connection requests, which are
-       still did not receive an acknowledgment from connecting client.
-       Default value is 1024 for systems with more than 128Mb of memory,
-       and 128 for low memory machines. If server suffers of overload,
-       try to increase this number.
+       Maximal number of remembered connection requests, which have not
+       received an acknowledgment from connecting client.
+       The minimal value is 128 for low memory machines, and it will
+       increase in proportion to the memory of machine.
+       If server suffers from overload, try increasing this number.
 
 tcp_max_tw_buckets - INTEGER
        Maximal number of timewait sockets held by system simultaneously.
@@ -397,7 +397,7 @@ tcp_rmem - vector of 3 INTEGERs: min, default, max
        net.core.rmem_max.  Calling setsockopt() with SO_RCVBUF disables
        automatic tuning of that socket's receive buffer size, in which
        case this value is ignored.
-       Default: between 87380B and 4MB, depending on RAM size.
+       Default: between 87380B and 6MB, depending on RAM size.
 
 tcp_sack - BOOLEAN
        Enable select acknowledgments (SACKS).
@@ -524,6 +524,11 @@ tcp_thin_dupack - BOOLEAN
        Documentation/networking/tcp-thin.txt
        Default: 0
 
+tcp_challenge_ack_limit - INTEGER
+       Limits number of Challenge ACK sent per second, as recommended
+       in RFC 5961 (Improving TCP's Robustness to Blind In-Window Attacks)
+       Default: 100
+
 UDP variables:
 
 udp_mem - vector of 3 INTEGERs: min, pressure, max