Proxy Authentication

Proxy authentication decides who can use a provider’s gateways and how usage is counted. In practice it’s either IP allowlisting or Username/Password per connection. For how auth fits with networks and sessions, see the proxy services overview, then choose the model that fits your setup.

What is proxy authentication?

Proxy authentication is the access gate a provider enforces at the gateway. In practice it is either IP allowlist or Username/Password on each connection.

It exists to verify the caller, tie traffic to an account or team, and apply plan limits. Your choice affects setup effort, portability, and how easily teammates and CI jobs connect.

Methods at a glance

IP Authentication

IP allowlist grants access to connections coming from registered IPv4 or IPv6 addresses or ranges. It is marginally faster and slightly more anonymous because no credentials are sent.

Add one or more public egress IPs or narrow CIDRs in the provider panel. This model is ideal for static offices or fixed servers. It breaks when the egress changes, so hotel Wi-Fi, CGNAT, or cloud redeploys require updating the allowlist or automating it via API. Use the smallest viable range and remove stale entries.
For configuration details and scripts, read  IP whitelist authentication.

Login & Password Authentication

Username/Password sends credentials with each connection and works from any network without touching allowlists. It fits laptops, containers, CI, and teams that hop between networks.

The tradeoff is secret handling and minor overhead. Scope credentials per project or per user, rotate on schedule, and prefer environment variables or a vault over hardcoding.
For setup patterns and header examples, see Username & Password authentication.

How to choose

Use IP allowlist when your egress is stable and centrally controlled. Use Username/Password when you need mobility, per-user access, or rotation.

A simple rule: if you can guarantee one predictable public IP for everything, allowlist minimizes moving parts; if your IP is unpredictable or you need per-user audit, credentials win.

Rotation, sessions, and gateways

Auth does not rotate exits by itself; rotation is a property of the gateway or pool. What changes is how you request stickiness and options.

With Username/Password, providers commonly embed parameters in the username to request a country, a sticky session key, or a time-bound session. With allowlist, you typically select rotation or stickiness by choosing specific hostnames or ports published by the provider.

Team access and offboarding

Team access works best with unique credentials per person or service so you can audit and revoke cleanly.

Assign one credential per teammate or job for clear attribution, rotate passwords on a schedule, and avoid shared logins. For allowlists, concentrate environments behind one NAT per environment to keep the panel clean; when staff changes, remove the affected credential or NAT IP without touching others.

Limits and plan behavior

Limits control throughput regardless of the auth method.

Tie credentials or allowlist entries to the plan that matches target concurrency, and if sub-accounts are available, route heavy jobs through their own credential to avoid collisions.

Rollout checklist

Standardize on one authentication method per environment and document ownership, rotation, and revocation.

Create a single source of truth for credentials and IP entries, label items by role or environment, define session lifetime rules for sticky usage, and keep a simple changelog of created and removed access.

FAQs

Q1. Is IP allowlist faster than Username/Password?
Yes, slightly. There is no credentials exchange on each connection, which removes a small step. The difference is minor for most workloads.

Q2. Can I use both methods at the same time?
Usually yes. Many providers allow both so you can mix per-user access for mobile or contractor devices with allowlist on fixed servers.

Q3. My ISP changes my IP. What should I choose?
Use Username/Password or automate allowlist updates via the provider API when your public IP changes.

Q4. Do credentials work with SOCKS and HTTP?
Yes. Both SOCKS5 and HTTP/HTTPS proxies typically support credentials, although option names differ by client.

Q5. How do I keep credentials out of logs and repos?
Use environment variables, a secrets manager, or a profile file outside the repo. Avoid embedding username:password@ in shared command history.

Related in this topic

• Private vs Shared
  
• Static vs Rotating
  
• SOCKS vs HTTP Proxies