Operation Manual – QoSH3C S3610&S5510 Series Ethernet SwitchesChapter 2 Traffic Classification, TP, and TSConfiguration2-3services with low delay, low packet loss ratio, low jitter, and assured bandwidth(such as virtual leased line);z Assured forwarding (AF) class: This class is further divided into four subclasses(AF1/2/3/4) and a subclass is further divided into three drop priorities, so the AFservice level can be segmented. The QoS rank of the AF class is lower than that ofthe EF class;z Class selector (CS) class: This class comes from the IP ToS field and includeseight subclasses;z Best Effort (BE) class: This class is a special class without any assurance in theCS class. The AF class can be degraded to the BE class if it exceeds the limit.Current IP network traffic belongs to this class by default.Table 2-2 Description on DSCP precedence valuesDSCP value (decimal) DSCP value (binary) Description46 101110 ef10 001010 af1112 001100 af1214 001110 af1318 010010 af2120 010100 af2222 010110 af2326 011010 af3128 011100 af3230 011110 af3334 100010 af4136 100100 af4238 100110 af438 001000 cs116 010000 cs224 011000 cs332 100000 cs440 101000 cs548 110000 cs656 111000 cs70 000000 be (default)
