HP T1453-90001 manual How is 802.1p Priority Set?

Overview of Installation and Configuration

How is 802.1p Priority Set?

How is 802.1p Priority Set?

IP packets are classified and marked into different priority levels and the markings are transported through a type of service (ToS) octet in the IPv4 header and a traffic class field in the IPv6 header.

HP-UX end stations transmit IPv4 type-of-service (ToS) values but do not enforce priority. The end stations perform ToS-to-802.1p conversion and vice-versa for IP packets depending on how the VLAN overrides are set. They also allow 802.1p priority setting for non-IP packets.

Priority may be set by user, destination address, input port, output port, access priority, or by VLAN. User priority is a 3-bit field which allows priority information to be encoded in the frame. The eight levels of IEEE 802.1p recommended user priorities are shown in Table 2-3.

Table 2-3	ToS to 802.1 User Priority Mappings Based on IP Precedence
	HP WebQoS ToS	IEEE 802.1p
		User		Traffic Type
	Value Range
		Priority
	0xE0 - 0xFF	7	(highest)	Network Management
	0xC0 - 0xDF	6		Voice
	0xA0 - 0xBF	5		Video
	0x80 - 0x9F	4		Controlled Load
	0x60 - 0x7F	3		Excellent Effort
	0x40 - 0x5F	0	(routine	Best Effort
		traffic)
	0x20 - 0x3F	2		Undefined
	0x00 - 0x1F	1	(lowest)	Background

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