[P4-discuss] mac address learning & generate_digest

胡鼎原 hdy at bupt.edu.cn
Wed Oct 19 22:15:44 EDT 2016


Hi,
I tried to learn `l2_switch.p4`. But I can’t understand about `generate_digest`.
I notice it is used for send data to outside of the scope of P4 or might also be used to represent a self-updating operation such as address learning.

1. Where the mac address learning result is stored?
2. Why doesn’t store it in `register`?
3. Can bmv2 run `l2_switch.p4` correctly without runtime API ?
4. What is parameter `receive` means in primitive action `generate_digest(receiver, field_list)`?
      And why MAC_LEARN_RECEIVER = 1024 ?

--
Best Regards,
Dingyuan Hu
Beijing University of Posts and Telecommunications







More information about the P4-discuss mailing list