Glossary · Proxies
Backconnect proxy
A backconnect proxy is a single gateway address that a client connects to while the gateway forwards each connection out through one of many exit IPs behind it, so the client configures one host, port and set of credentials instead of a list of proxies.
Reviewed 30 Oct 2026
USERNAME_pool-arcfast_country-de_city-munich_session-k3f9a1x2_sesstime-10gateway: proxy.arcproxies.io:8000 (HTTP and SOCKS5 on the same port)How the gateway decides the exit
The client authenticates to the gateway — with the Proxy-Authorization header for HTTP (RFC 9110) or the username/password subnegotiation for SOCKS5 (RFC 1929). Providers encode the routing options in that username, because it is the one field every client library passes through untouched.
On ARC's rotating gateway the username is read token by token:
| Token | Meaning |
|---|---|
_pool-arc / arcfast / arcultra | ARC Basic, ARC Fast or ARC Ultra |
_country-de | Exit country, ISO 3166-1 alpha-2, lowercase |
_city-munich | Exit city from the published metro list |
_session-<id>_sesstime-10 | Hold one exit for 10 minutes |
_fastmode-true | Prefer the fastest nodes; free on every rotating pool |
Backconnect gateway vs a proxy list
| Proxy list | Backconnect gateway | |
|---|---|---|
| What you configure | Many host:port pairs | One host:port |
| Dead exits | You detect and remove them | The gateway draws another |
| Location choice | Pick the right IP from the list | A token in the username |
| Rotation | Your code | The gateway, or held via a session handle |
What the gateway can and cannot see
For HTTPS, the client opens a tunnel with HTTP CONNECT or SOCKS5, and TLS runs end to end through it. The gateway sees the destination host and port and how many bytes pass, which is what per-GB pricing meters; it does not see URLs, headers or page content. That is also why options must travel in the credentials rather than in request headers.
FAQ
Questions
Something not covered? Write to contact@arcproxies.io.
Is a backconnect proxy the same as a rotating proxy?
Not quite. Backconnect is the architecture, one gateway in front of many exits; rotation is one behaviour of that gateway. The same backconnect endpoint can rotate on every connection or hold one exit for a sticky session.
Can a backconnect proxy read my HTTPS traffic?
No. HTTPS through a proxy runs inside a tunnel, so TLS is negotiated between your client and the site. The gateway sees the destination host and port and the byte count, not the URLs, headers or content.
Which host and port does ARC's backconnect gateway use?
The rotating pools share one gateway, proxy.arcproxies.io on port 8000, for both HTTP and SOCKS5. ARC Mobile endpoints are generated separately on the mobile gateway and are not composed by hand.
Sources & review
Last reviewed by the ARC Proxies team. Prices are read from the live catalog at build time.
In practice