Class of Service (CoS) Settings
Each of the 256 CoS entries, indexed 0-255, are mapped to a 802.1p priority (0-7), ToS value (0-255), virtual txq-reference (0-15) and virtual irl-reference (0-31). A virtual reference is used to abstract the hardware capabilities from the CoS row. This allows for the management entity such as Extreme Management Center to create user CoS profiles based on the user and not multiple user profiles for each hardware platform. The virtual references are then mapped to actual hardware resources. On ExtremeXOS, the txq-reference mappings 0-7 are fixed to QoS profiles 1-8 and txq-reference 8-15 map to QoS profile 8. The irl-reference mappings are also fixed to the per-port ingress meters. This mapping is dependent on the number of per-port ingress meters supported on the platform.CoS entries 0-7 are equivalent to the dot1p traffic groupings for priorities 0-7.