Editing Quality of service (section)

==Standards==
Quality of service in the field of [[telephony]] was first defined in 1994 in [[ITU-T]] Recommendation E.800. This definition is very broad, listing 6 primary components: Support, Operability, Accessibility, Retainability, Integrity and Security.<ref name="E.800">{{cite web |title= E.800: Terms and definitions related to quality of service and network performance including dependability |date= August 1994 |work= ITU-T Recommendation |url= http://www.itu.int/rec/T-REC-E.800/en |access-date= October 14, 2011 }} Updated September 2008 as ''Definitions of terms related to quality of service''</ref> In 1998 the ITU published a document discussing QoS in the field of data networking. X.641 offers a means of developing or enhancing standards related to QoS and provide concepts and terminology that should assist in maintaining the consistency of related standards.<ref>{{cite web |title= X.641: Information technology - Quality of service: framework |work=ITU-T Recommendation |date= December 1997 |url= http://www.itu.int/rec/T-REC-X.641/en }}</ref>

Some QoS-related IETF [[Request for Comments]] (RFC)s are {{citation |title= Definition of the Differentiated services Field (DS Field) in the IPv4 and IPv6 Headers |date=December 1998|rfc=2474|last1=Baker|first1=Fred|last2=Black|first2=David L.|last3=Nichols|first3=Kathleen|last4=Blake|first4=Steven L.|doi=10.17487/RFC2474 |doi-access=free}}, and {{citation |title=Resource ReSerVation Protocol (RSVP) |date=September 1997|rfc=2205|last1=Braden|first1=Robert T.|last2=Zhang|first2=Lixia|last3=Berson|first3=Steven|last4=Herzog|first4=Shai|last5=Jamin|first5=Sugih|editor-first1=R. |editor-last1=Braden |doi=10.17487/RFC2205 |doi-access=free}}; both these are discussed above. The IETF has also published two RFCs giving background on QoS: {{citation |rfc=2990 |title= Next Steps for the IP QoS Architecture|date= November 2000|last1= Huston|first1= Geoff|doi= 10.17487/RFC2990}}, and {{citation |rfc=3714 |title=IAB Concerns Regarding Congestion Control for Voice Traffic in the Internet|year=2004 |doi=10.17487/RFC3714 |last1=Floyd |first1=S. |last2=Kempf |first2=J. |editor-first1=J. |editor-last1=Kempf }}.

The IETF has also published {{citation |rfc=4594 |title=Configuration Guidelines for DiffServ Service Classes|date=August 2006|last1=Baker|first1=Fred|last2=Babiarz|first2=Jozef|last3=Chan|first3=Kwok Ho|doi=10.17487/RFC4594 |doi-access=free}} as an informative or ''best practices'' document about the practical aspects of designing a QoS solution for a [[DiffServ]] network. The document tries to identify applications commonly run over an IP network, groups them into traffic classes, studies the treatment required by these classes from the network, and suggests which of the QoS mechanisms commonly available in routers can be used to implement those treatments.