I have a Cisco small business switch and I am wondering what I will gain (or lose) by enabling "TCP congestion avoidance". I read the definition of it but how does one know when one should use it?
I have problem with oracle solaris 10 running on oracle sparc T4-2 server.
Os information: 5.10 Generic_150400-03 sun4v sparc sun4v
Output from tcpstat.d script
TCP bytes: out outRetrans in inDup inUnorder
6833763 7300 98884 0... (2 Replies)
I have a client with a meshed Cisco backbone.
6500's on top, Nexus 7000 in the middle and 4500's in bottom.
Solaris 10 servers connected to the 4500's backing up to a RedHat Linux backup server connected to the Nexus 7000's. The traffic is routed from 4500 --> Nexus 7000 --> 6500 --> Nexus 7000... (3 Replies)
I have noticed that the initial congestion window in my traces is 8920bytes~=6*1448. rfc3390 states the initial cwand should be max 4000 bytes(around 3*1448).
At first i thought it might be because i'm running my server on mac os x, so apple might have modified the tcp stack. Therefore I tried... (2 Replies)
I was looking at differnt types of TCP Congestion Avoidance algorithms and realized that they are almost all tailored toward "high speed networks with high latency" (aka. LFN)
Anybody know of a Congestion Avoidance algorithm used in low-latency networks? (3 Replies)
I am trying to develop a c++ application which will communicate with client through SSL(Not https).We are using self-signed certificates.
I have installed openssl and boost library.
I have tried some boost sample code also and its working.
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Hello everybody,
It's me again, i need your help!
I was almost finishing a program when it crashed, because of TCP segments with the TCP Options enabled.
I am able to control every field of every packet i receive, except of those using TCP Options. Is there a way to determine if a packet is... (0 Replies)
I have written a TCP/IP client and server program. The client sends a message to the server and then the server sends a file back to the client. The client reads the buffer and stores it another file in the client side.
I need to know what are the various exceptions that I need to handle in... (0 Replies)
Hello ,
I need to convert X.25 packets to IP packets how should i proceed .......... Please help me , regarding this matter or atleast suggest me some material which can be read regarding this .
Bye (2 Replies)
CC_CUBIC(4) BSD Kernel Interfaces Manual CC_CUBIC(4)NAME
cc_cubic -- CUBIC Congestion Control Algorithm
DESCRIPTION
The CUBIC congestion control algorithm was designed to provide increased throughput in fast and long-distance networks. It attempts to main-
tain fairness when competing with legacy NewReno TCP in lower speed scenarios where NewReno is able to operate adequately.
The congestion window is increased as a function of the time elapsed since the last congestion event. During regular operation, the window
increase function follows a cubic function, with the inflection point set to be the congestion window value reached at the last congestion
event. CUBIC also calculates an estimate of the congestion window that NewReno would have achieved at a given time after a congestion event.
When updating the congestion window, the algorithm will choose the larger of the calculated CUBIC and estimated NewReno windows.
CUBIC also backs off less on congestion by changing the multiplicative decrease factor from 1/2 (used by standard NewReno TCP) to 4/5.
The implementation was done in a clean-room fashion, and is based on the Internet Draft and paper referenced in the SEE ALSO section below.
MIB Variables
There are currently no tunable MIB variables.
SEE ALSO cc_chd(4), cc_hd(4), cc_htcp(4), cc_newreno(4), cc_vegas(4), mod_cc(4), tcp(4), mod_cc(9)
Sangtae Ha, Injong Rhee, and Lisong Xu, CUBIC for Fast Long-Distance Networks, http://tools.ietf.org/id/draft-rhee-tcpm-cubic-02.txt.
Sangtae Ha, Injong Rhee, and Lisong Xu, "CUBIC: a new TCP-friendly high-speed TCP variant", SIGOPS Oper. Syst. Rev., 5, 42, 64-74, July 2008.
ACKNOWLEDGEMENTS
Development and testing of this software were made possible in part by grants from the FreeBSD Foundation and Cisco University Research Pro-
gram Fund at Community Foundation Silicon Valley.
HISTORY
The cc_cubic congestion control module first appeared in FreeBSD 9.0.
The module was first released in 2009 by Lawrence Stewart whilst studying at Swinburne University of Technology's Centre for Advanced Inter-
net Architectures, Melbourne, Australia. More details are available at:
http://caia.swin.edu.au/urp/newtcp/
AUTHORS
The cc_cubic congestion control module and this manual page were written by Lawrence Stewart <lstewart@FreeBSD.org> and David Hayes
<david.hayes@ieee.org>.
BSD September 15, 2011 BSD
