Tagging - Hirschmann Power MICE User Manual

Traffic control

8.4.2 Tagging

The VLAN tag is integrated into the MAC data frame for the VLAN and prio-
ritization functions in accordance with the IEEE 802.1 Q standard. The VLAN
tag consists of 4 Bytes. It is inserted between the source address field and
the type field.
With data packets with VLAN tag, the Switch evaluates
D
the priority information at all times, and
D
the VLAN information, if VLANs have been set up.
Data packets whose VLAN tags contain priority information but no VLAN
information (VLAN ID = 0) are known as "Priority Tagged Frames".
Entered Priority class
priority (default)
0 2
1 0
2 1
3 3
4 4
5 5
6 6
7 7
Table 9: Assignment of the priorities listed in the tag to the four priority classes
Note: Network logs and redundancy mechanisms use the highest priority
classes 3 (RS20/30/40, MS20/30, MACH 1000, OCTOPUS) and 7 (Power
MICE, MACH 4000). You therefore select other priority classes for application
data.
136
IEEE 802.1D traffic type
Best Effort (default)
Background
Standard
Excellent Effort (business critical)
Controlled load
(streaming multimedia)
Video, less than 100 millisconds of latency and jitter
Voice; less than 10 milliseconds of latency and jitter
Network Control reserved traffic
8.4 Prioritization
Basic - L3P
Release 3.1 06/07