Gerrit Renker a3cbdde8e9 dccp ccid-3: Preventing Oscillations ... This implements [RFC 3448, 4.5], which performs congestion avoidance behaviour by reducing the transmit rate as the queueing delay (measured in terms of long-term RTT) increases. Oscillation can be turned on/off via a module option (do_osc_prev) and via sysfs (using mode 0644), the default is off. Overflow analysis: ------------------ * oscillation prevention is done after update_x(), so that t_ipi <= 64000; * hence the multiplication "t_ipi * sqrt(R_sample)" needs 64 bits; * done using u64 for sqrt_sample and explicit typecast of t_ipi; * the divisor, R_sqmean, is non-zero because oscillation prevention is first called when receiving the second feedback packet, and tfrc_scaled_rtt() > 0. A detailed discussion of the algorithm (with plots) is on http://www.erg.abdn.ac.uk/users/gerrit/dccp/notes/ccid3/sender_notes/oscillation_prevention/ The algorithm has negative side effects: * when allowing to decrease t_ipi (leads to a large RTT) and * when using it during slow-start; both uses are therefore disabled. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>		2008-09-04 07:45:43 +02:00
..
lib	dccp ccid-3: Preventing Oscillations	2008-09-04 07:45:43 +02:00
ccid2.c	tcp/dccp: Consolidate common code for RFC 3390 conversion	2008-09-04 07:45:39 +02:00
ccid2.h	dccp ccid-2: Replace broken RTT estimator with better algorithm	2008-09-04 07:45:39 +02:00
ccid3.c	dccp ccid-3: Preventing Oscillations	2008-09-04 07:45:43 +02:00
ccid3.h	dccp ccid-3: Preventing Oscillations	2008-09-04 07:45:43 +02:00
Kconfig	dccp ccid-3: Measuring the packet size s with regard to rfc3448bis-06	2008-09-04 07:45:42 +02:00
Makefile