Editing Traffic shaping (section)

{{Short description|Communication bandwidth management technique}}

'''Traffic shaping''' is a [[bandwidth management]] technique used on [[computer networks]] which delays some or all [[datagram]]s to bring them into compliance with a desired ''traffic profile''.<ref>[http://tools.ietf.org/html/rfc2475#section-2.3.3.3 IETF RFC 2475] "An Architecture for Differentiated Services" section 2.3.3.3 - Internet standard definition of "Shaper"</ref><ref>[http://www.itu.int/rec/T-REC-I.371-200403-I/en ITU-T Recommendation I.371: Traffic control and congestion control in B-ISDN] Section 7.2.7 defines traffic shaping as a ''traffic control mechanism'' which "alters the traffic characteristics of a stream of cells on a VCC or a VPC to achieve a desired modification of those traffic characteristics, in order to achieve better network efficiency whilst meeting the QoS objectives or to ensure conformance at a subsequent interface. ... Shaping modifies traffic characteristics of a cell flow with the consequence of increasing the mean cell transfer delay."</ref> Traffic shaping is used to optimize or guarantee performance, improve [[Network latency|latency]], or increase usable [[Bandwidth (computing)|bandwidth]] for some kinds of packets by delaying other kinds. It is often confused with [[Traffic policing (communications)|traffic policing]], the distinct but related practice of [[packet dropping]] and [[IP traceback#Packet marking|packet marking]].<ref>{{cite web|url=http://www.cisco.com/en/US/tech/tk543/tk545/technologies_tech_note09186a00800a3a25.shtml| publisher=[[Cisco Systems]]|title=Cisco Tech Notes: Comparing Traffic Policing and Traffic Shaping for Bandwidth Limiting. Document ID: 19645|date=Aug 10, 2005|access-date=2014-03-08}} Graphs illustrate differences in typical output</ref>

The most common type of traffic shaping is application-based traffic shaping.<ref>{{cite book |doi=10.1145/1452520.1452523 |isbn=978-1-60558-334-1 |date=October 2008 |chapter-url=https://www.measurementlab.net/publications/detecting-bittorrent-blocking.pdf |chapter=Detecting BitTorrent Blocking |title=Proceedings of the 8th ACM SIGCOMM conference on Internet measurement conference - IMC '08 |last1=Dischinger |first1=Marcel |last2=Mislove |first2=Alan |last3=Haeberlen |first3=Andreas |last4=Gummadi |first4=Krishna P. |page=3 |s2cid=429226 }}</ref>{{failed verification|reason=Paper discusses blocking, shaping is suggested follow-on work.|date=January 2018}} In application-based traffic shaping, fingerprinting tools are first used to identify applications of interest, which are then subject to shaping policies. Some controversial cases of application-based traffic shaping include [[bandwidth throttling]] of [[peer-to-peer file sharing]] traffic. Many application protocols use [[encryption]] to circumvent application-based traffic shaping.

Another type of traffic shaping is route-based traffic shaping. Route-based traffic shaping is conducted based on previous-[[Hop (telecommunications)|hop]] or next-hop information.<ref>[http://research.microsoft.com/apps/pubs/default.aspx?id=136790 Ascertaining the Reality of Network Neutrality Violation in Backbone ISPs], ACM HotNets 2008</ref>