| DCTCP (DataCenter TCP) | 
 | ---------------------- | 
 |  | 
 | DCTCP is an enhancement to the TCP congestion control algorithm for data | 
 | center networks and leverages Explicit Congestion Notification (ECN) in | 
 | the data center network to provide multi-bit feedback to the end hosts. | 
 |  | 
 | To enable it on end hosts: | 
 |  | 
 |   sysctl -w net.ipv4.tcp_congestion_control=dctcp | 
 |   sysctl -w net.ipv4.tcp_ecn_fallback=0 (optional) | 
 |  | 
 | All switches in the data center network running DCTCP must support ECN | 
 | marking and be configured for marking when reaching defined switch buffer | 
 | thresholds. The default ECN marking threshold heuristic for DCTCP on | 
 | switches is 20 packets (30KB) at 1Gbps, and 65 packets (~100KB) at 10Gbps, | 
 | but might need further careful tweaking. | 
 |  | 
 | For more details, see below documents: | 
 |  | 
 | Paper: | 
 |  | 
 | The algorithm is further described in detail in the following two | 
 | SIGCOMM/SIGMETRICS papers: | 
 |  | 
 |  i) Mohammad Alizadeh, Albert Greenberg, David A. Maltz, Jitendra Padhye, | 
 |     Parveen Patel, Balaji Prabhakar, Sudipta Sengupta, and Murari Sridharan: | 
 |       "Data Center TCP (DCTCP)", Data Center Networks session | 
 |       Proc. ACM SIGCOMM, New Delhi, 2010. | 
 |     http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp-final.pdf | 
 |     http://www.sigcomm.org/ccr/papers/2010/October/1851275.1851192 | 
 |  | 
 | ii) Mohammad Alizadeh, Adel Javanmard, and Balaji Prabhakar: | 
 |       "Analysis of DCTCP: Stability, Convergence, and Fairness" | 
 |       Proc. ACM SIGMETRICS, San Jose, 2011. | 
 |     http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp_analysis-full.pdf | 
 |  | 
 | IETF informational draft: | 
 |  | 
 |   http://tools.ietf.org/html/draft-bensley-tcpm-dctcp-00 | 
 |  | 
 | DCTCP site: | 
 |  | 
 |   http://simula.stanford.edu/~alizade/Site/DCTCP.html |