metrotek Bercut-MMT, Operation Manual

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B. Traffic Types and Priorities
B.1 VLAN Tags
Table B.1: Traffic Types and Priorities
Value Description
0 (Default) Best Effort
1 Background
2 Excellent Effort
3 Critical Application
5 Voice
6 Internetwork Control
7 Network Control
Network Control and Internetwork Control are reserved for network manage-
ment messages. This traffic type is considered as high priority. Priorities 4
and 5 can be used for delay sensitive traffic, such as video and voice. Traffic
priorities from 3 to 1 are used for different tasks: from streaming applications
to FTP traffic that is able to overcome possible losses. Class 0 (
best effort
delivery rate ) is assigned to a traffic with lowest priority and is used when no
other class is assigned [9].
B.2 Type of Service
According to RFC 791, eight frame priority values are supported [10].
Table B.2: Values of the Field Precedence
Value Name Description
000 Routine Normal priority
001 Priority Preferred priority
010 Immediate Immediate priority
Bercut-MMT: Ethernet Networks Analysis