When it fits#
- Servers and VPS with a static public IPv4.
- Tools that cannot hold credentials: browser proxy flags, some anti-detect profiles, appliances.
- Environments where a leaked password would be worse than a leaked address.
When it does not#
- Laptops on home or mobile connections, containers with changing egress, serverless functions.
- Shared egress (offices, universities, CGNAT): anyone behind the same address would be authenticated as you.
- IPv6-only hosts, when the provider whitelists IPv4 only.
Targeting still works#
On rotating pools the username carries the location and session parameters. With a whitelisted address you still send a username (any password) so the gateway can read them.
How it works at ProxShift#
ProxShift whitelists up to 50 IPv4 addresses per account, applied within a minute, from the dashboard or POST /v1/whitelist; whitelisted connections carry parameters in the username and any password.