LevelOne GSW-2690 user manual 127

User Manual

Function name:

T-Type TOS

Function description:

IP TOS Priority affect TOS fields of IP header, you can find it has 8-bit SERVICE TYPE field that specifies how the datagram should be handled. The field could be divided into six subfields as follows, PRECEDENCE (3 bits), D- Type (Delay Priority, 1 bit ), T-Type (Throughput Priority, 1bit), R-Type (Reliability Priority, 1bit ), M-Type (Monetary Cost Priority, 1bit ), and UNUSED. PRECEDENCE 3-bits can arrange 8 kinds of priorities corresponding to the 0~7 priority in the following priority diagram. TOS Delay Priority Mapping works while T-TYPE in TOS field of IP header of the packets received by the switch is configured.

Parameter description:

TOS Throughput Priority Mapping:

Each Priority can select any of Queue 0 ~ Queue 3. In Default, Priority 0 is mapping to Queue 0, Priority 1 is mapping to Queue 0, Priority 2 is mapping to Queue 1, Priority 3 is mapping to Queue 1, Priority 4 is mapping to Queue 2, Priority 5 is mapping to Queue 2, Priority 6 is mapping to Queue 3, and Priority 0 is mapping to Queue 3.

Fig. 3-65

Publication date: June, 2005

Revision A1

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