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33 .Dd September 15, 2011
38 .Nd Modular congestion control
40 The modular congestion control framework allows the TCP implementation to
41 dynamically change the congestion control algorithm used by new and existing
43 Algorithms are identified by a unique
46 Algorithm modules can be compiled into the kernel or loaded as kernel modules
51 The default algorithm is NewReno, and all connections use the default unless
52 explicitly overridden using the TCP_CONGESTION socket option (see
55 The default can be changed using a
57 MIB variable detailed in the
61 The framework exposes the following variables in the
66 .Bl -tag -width ".Va available"
68 Read-only list of currently available congestion control algorithms by name.
70 Returns the current default congestion control algorithm when read, and changes
72 When attempting to change the default algorithm, this variable should be set to
73 one of the names listed by the
74 .Va net.inet.tcp.cc.available
87 Development and testing of this software were made possible in part by grants
88 from the FreeBSD Foundation and Cisco University Research Program Fund at
89 Community Foundation Silicon Valley.
93 modular congestion control framework first appeared in
96 The framework was first released in 2007 by James Healy and Lawrence Stewart
97 whilst working on the NewTCP research project at Swinburne University of
98 Technology's Centre for Advanced Internet Architectures, Melbourne, Australia,
99 which was made possible in part by a grant from the Cisco University Research
100 Program Fund at Community Foundation Silicon Valley.
101 More details are available at:
103 http://caia.swin.edu.au/urp/newtcp/
108 facility was written by
109 .An Lawrence Stewart Aq lstewart@FreeBSD.org ,
110 .An James Healy Aq jimmy@deefa.com
112 .An David Hayes Aq david.hayes@ieee.org .
114 This manual page was written by
115 .An David Hayes Aq david.hayes@ieee.org
117 .An Lawrence Stewart Aq lstewart@FreeBSD.org .