Internet-Security.com TCP port 9983 details

Sia (siad / Sia-UI), the decentralized cloud storage platform, uses TCP port 9983 for its Renter-Host Protocol v2 (RHPv2).
In practice, Sia host nodes expose/forward TCP 9983 (alongside 9982 for RHPv1) to accept renter connections and contract traffic; the Sia gateway and API use 9981 and 9980 respectively.
Example: Sia host operators on Linux/Windows routinely open TCP 9983 in firewalls and on home/ISP routers to enable hosting on the Sia network.

TCP 9983