LevelOne GSW-2690 User Manual

Page of 265
User Manual    
Publication date: June, 2005  
Revision A1 
130 
 
 
Function name: 
DSCP Setting 
Function description: 
In the late 1990s, the IETF redefined the meaning of the 8-bit SERVICE TYPE 
field to accommodate a set of differentiated services (DS). Under the 
differentiated services interpretation, the first six bits comprise a codepoint, 
which is sometimes abbreviated DSCP, and the last two bits are left unused. 
DSCP can form total 64 (0~63) kinds of Traffic Class based on the 
arrangement of 6-bit field in DSCP of the IP packet.  In the switch, user is 
allowed to set up these 64 kinds of Class that belong to any of queue 0~3.  
Parameter description: 
DSCP Priority Mapping: 
64 kinds of priority traffic as mentioned above, user can set up any of 
Queue 0~3. In default, Priority 0~15 are mapping to Queue 0, Priority 
16~31 are mapping to Queue 1, Priority 32~47 are mapping to Queue 0, 
Priority 48~63 are mapping to Queue 0. 
 
 
                 Fig. 3-68