IEEE P802.1p was a task group active from 1995 to 1998, responsible for adding traffic class expediting and dynamic multicast filtering to the IEEE 802.1D standard. The task group developed a mechanism for implementing quality of service (QoS) at the media access control (MAC) level. Although this technique is commonly referred to as IEEE 802.1p, the group's work with the new priority classes and Generic Attribute Registration Protocol (GARP) was not published separately but was incorporated[1] into a major revision of the standard, IEEE 802.1D-1998,[2] which subsequently was incorporated into IEEE 802.1Q-2014 standard.[3] The work also required a short amendment extending the frame size of the Ethernet standard by four bytes which was published as IEEE 802.3ac in 1998.
The QoS technique developed by the working group, also known as class of service (CoS), is a 3-bit field called the Priority Code Point (PCP) within an Ethernet frame header when using VLAN tagged frames as defined by IEEE 802.1Q. It specifies a priority value of between 0 and 7 inclusive that can be used by QoS disciplines to differentiate traffic.
Eight different classes of service are available as expressed through the 3-bit PCP field in an IEEE 802.1Q header added to the frame. The way traffic is treated when assigned to any particular class is undefined and left to the implementation. The IEEE, however, has made some broad recommendations:[4]
Note that the above recommendations have been in force since IEEE 802.1Q-2005 and were revised from the original recommendations in IEEE 802.1D-2004 to better accommodate differentiated services for IP networking.
^"802.1Q-2014 - Bridges and Bridged Networks". IEEE.
^IEEE Std 802.1Q-2014, Bridges and Bridged Networks(PDF), Table I-2 - Traffic type acronyms
External linksedit
IEEE 802.1D-2004 (contains original 802.1p changes - now part of 802.1Q-2014)
IEEE 802.1Q-2014 (incorporates 802.1D)
April 13, 2024
ieee, p802, task, group, active, from, 1995, 1998, responsible, adding, traffic, class, expediting, dynamic, multicast, filtering, ieee, standard, task, group, developed, mechanism, implementing, quality, service, media, access, control, level, although, this,. IEEE P802 1p was a task group active from 1995 to 1998 responsible for adding traffic class expediting and dynamic multicast filtering to the IEEE 802 1D standard The task group developed a mechanism for implementing quality of service QoS at the media access control MAC level Although this technique is commonly referred to as IEEE 802 1p the group s work with the new priority classes and Generic Attribute Registration Protocol GARP was not published separately but was incorporated 1 into a major revision of the standard IEEE 802 1D 1998 2 which subsequently was incorporated into IEEE 802 1Q 2014 standard 3 The work also required a short amendment extending the frame size of the Ethernet standard by four bytes which was published as IEEE 802 3ac in 1998 The QoS technique developed by the working group also known as class of service CoS is a 3 bit field called the Priority Code Point PCP within an Ethernet frame header when using VLAN tagged frames as defined by IEEE 802 1Q It specifies a priority value of between 0 and 7 inclusive that can be used by QoS disciplines to differentiate traffic Contents 1 Priority levels 2 See also 3 References 4 External linksPriority levels editEight different classes of service are available as expressed through the 3 bit PCP field in an IEEE 802 1Q header added to the frame The way traffic is treated when assigned to any particular class is undefined and left to the implementation The IEEE however has made some broad recommendations 4 PCP value Priority Acronym Traffic types1 0 lowest BK Background0 1 default BE Best effort2 2 EE Excellent effort3 3 CA Critical applications4 4 VI Video lt 100 ms latency and jitter5 5 VO Voice lt 10 ms latency and jitter6 6 IC Internetwork control7 7 highest NC Network controlNote that the above recommendations have been in force since IEEE 802 1Q 2005 and were revised from the original recommendations in IEEE 802 1D 2004 to better accommodate differentiated services for IP networking See also editIEEE 802 1 IEEE 802 11e IEEE 802 3 Type of service ToS Ethernet priority flow controlReferences edit IEEE 802 1 p 802 1p section failed verification IEEE 802 1D 1998 802 1Q 2014 Bridges and Bridged Networks IEEE IEEE Std 802 1Q 2014 Bridges and Bridged Networks PDF Table I 2 Traffic type acronymsExternal links editIEEE 802 1D 2004 contains original 802 1p changes now part of 802 1Q 2014 IEEE 802 1Q 2014 incorporates 802 1D Retrieved from https en wikipedia org w index php title IEEE P802 1p amp oldid 1034761528, wikipedia, wiki, book, books, library,
