A network operator wants to make sure voice data is prioritized. In this scenario, to which Ethernet traffic class should it be assigned.

The IEEE 802.1p standard, part of the IEEE 802.1Q specification for VLAN tagging, defines a 3-bit Priority Code Point (PCP) field to enable Quality of Service (QoS) at the MAC layer. This field allows for eight traffic classes (0-7). According to standard recommendations, traffic class 6 is designated for voice traffic. This class is engineered for applications with very low latency and jitter requirements (typically <10 ms), ensuring that real-time voice packets are prioritized over other types of data, such as video (class 5) or best-effort traffic (class 0), to maintain high-quality communication.

A. 0: This is the "Best Effort" class, the default priority for general traffic with no specific QoS requirements.

B. 2: This class is defined as "Spare" in the standard and is generally not used for specific traffic types.

C. 4: This class is for "Controlled Load" or video streaming, which is less sensitive to latency than voice traffic.

1. IEEE Std 802.1Q-2018

"IEEE Standard for Local and metropolitan area networks—Bridges and Bridged Networks." In Annex I (informative)

Table I-2

"Traffic type to priority and PCP mapping recommendations

" explicitly maps "Voice" traffic to Priority 6.

2. Ericsson AB

"QoS and Scheduling on the Router 6000

" Document Number: 2/221 02-FAP 130 519 Uen Rev C. Section 4.1

"Traffic Classes

" states: "The recommended mapping of traffic types to traffic classes is... Voice to TC6."

3. Stallings

W. (2016). Foundations of Modern Networking: SDN

NFV

and Cloud Computing. Pearson Education. In Chapter 6

"The Network and Transport Layers

" Section 6.4

"Quality of Service

" the text discusses IEEE 802.1p priority levels

aligning with the standard that assigns priority 6 to voice.