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RFC 9956 - A Non-Queue-Building Per-Hop Behavior (NQB PHB) for Differentiated Services

  • Status: Proposed Standard
  • Published: May 2026
  • Stream: IETF
  • Updates: RFC 8325
  • Recommended DSCP: 45 decimal, binary 101101, name NQB

Abstract​

This RFC specifies the Non-Queue-Building Per-Hop Behavior (NQB PHB) for Differentiated Services. NQB provides a shallow-buffered best-effort service that complements the Default deep-buffered best-effort service, so smooth, low-data-rate, application-limited microflows can avoid delay, delay variation, and loss caused by capacity-seeking traffic. The PHB is intended primarily for bottlenecks in access networks, does not rely on prioritization, and can be deployed without aggregate rate policing.

Contents​