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37 .Nd Modular congestion control
39 The modular congestion control framework allows the TCP implementation to
40 dynamically change the congestion control algorithm used by new and existing
42 Algorithms are identified by a unique
45 Algorithm modules can be compiled into the kernel or loaded as kernel modules
50 The default algorithm is NewReno, and all connections use the default unless
51 explicitly overridden using the TCP_CONGESTION socket option (see
54 The default can be changed using a
56 MIB variable detailed in the
60 The framework exposes the following variables in the
65 .Bl -tag -width ".Va available"
67 Read-only list of currently available congestion control algorithms by name.
69 Returns the current default congestion control algorithm when read, and changes
71 When attempting to change the default algorithm, this variable should be set to
72 one of the names listed by the
73 .Va net.inet.tcp.cc.available
86 Development and testing of this software were made possible in part by grants
87 from the FreeBSD Foundation and Cisco University Research Program Fund at
88 Community Foundation Silicon Valley.
92 modular congestion control framework first appeared in
95 The framework was first released in 2007 by James Healy and Lawrence Stewart
96 whilst working on the NewTCP research project at Swinburne University's Centre
97 for Advanced Internet Architectures, Melbourne, Australia, which was made
98 possible in part by a grant from the Cisco University Research Program Fund at
99 Community Foundation Silicon Valley.
100 More details are available at:
102 http://caia.swin.edu.au/urp/newtcp/
107 facility was written by
108 .An Lawrence Stewart Aq lstewart@FreeBSD.org ,
109 .An James Healy Aq jimmy@deefa.com
111 .An David Hayes Aq david.hayes@ieee.org .
113 This manual page was written by
114 .An David Hayes Aq david.hayes@ieee.org
116 .An Lawrence Stewart Aq lstewart@FreeBSD.org .