Hi Vijay,
Welcome to Audience Manager community!
Integration code is used as an alias for Data Source ID. So, it is used in Customer ID sync calls when we use the platform variable : d_cid_ic
For more info check this doc : CID Replaces DPID and DPUUID
If you want to qualify a user for a rule based trait using a pixel call or a parameter in the URL, then you can use the platform variable:
d_sid for rule based traits, check this doc: Pixel-based Data Transfers
Let me know if I understood your question correctly, and if the above info helps.
Thanks,
Varun Kalra