| .. _traffic-class-support: |
| |
| Traffic Classification |
| ####################### |
| |
| Overview |
| ******** |
| |
| `Traffic classification <https://en.wikipedia.org/wiki/Traffic_classification>`_ |
| is an automated process that categorizes computer network traffic according to |
| various parameters. For Zephyr, the VLAN priority code point (PCP) is used |
| to classify both received and sent network packets. See more information about |
| VLAN priority at `IEEE 802.1Q <https://en.wikipedia.org/wiki/IEEE_802.1Q>`_. |
| |
| By default, all network traffic is treated equal in Zephyr. If desired, the |
| option :kconfig:option:`CONFIG_NET_TC_TX_COUNT` can be used to set the number of |
| transmit queues. The option :kconfig:option:`CONFIG_NET_TC_RX_COUNT` can be used to set |
| the number of receive queues. Each traffic class queue corresponds to a |
| specific kernel work queue. Each kernel work queue has a priority. |
| The VLAN priority is mapped to a certain traffic class according to rules |
| specified in `IEEE 802.1Q spec`_ chapter I.3, chapter 8.6.6 table 8-4, |
| and chapter 34.5 table 34-1. Each traffic class is in turn mapped to a certain |
| kernel work queue. The maximum number of traffic classes for both Rx and Tx |
| is 8. |
| |
| See :zephyr_file:`subsys/net/ip/net_tc.c` for details of how various mappings are done. |
| |
| .. _IEEE 802.1Q spec: https://ieeexplore.ieee.org/document/6991462/ |
