A link to the device. Then it is gone.
Open access to a device’s interface when you need to get into it, work, and close it behind you. Nothing is installed on the device, nothing runs at your end, and nothing is left listening once you are finished.
Open it in a browser. Close it when you are done, and the route stops existing.
Access that does not sit there waiting.
Most remote access is permanent by design. A tunnel is built, an agent is installed, credentials are issued, and all of it stays in place whether anyone is using it or not. SIMSY Proxy is the opposite: it exists while you need it and not a minute longer.
Nothing on the device
No agent, no client, no software to install or update across a fleet. The device does not know it is reachable and does not have to be told.
Nothing left running
The route is created when you ask for it and torn down when you are finished. There is no standing access to inherit, forget about or audit later.
Nothing at your end
A browser. No client software, no VPN profile, no gateway to run. It works from a laptop, a phone or a machine you have never set up before.
Three steps and a browser tab.
Ask for access
Pick the device in the portal, or call the API. A secure URL is created for it.
Open it
The device’s own interface loads in your browser, exactly as it would if you were stood in front of it.
Close it
End the session and the route is removed. What was there a moment ago is no longer reachable by anyone.
Let someone in without letting them in.
Giving an outside engineer access to one machine normally means giving them access to your network. A VPN profile, a set of credentials, an account on a support platform, and a quiet hope that they only touch the thing they were asked to look at.
A proxy link goes to one device and nothing else. The manufacturer who needs to check their controller sees their controller. The contractor diagnosing a charge point sees that charge point. Neither of them is on your network, neither of them holds credentials, and when the job is finished the link stops working.
Nobody has to be onboarded, and nobody has to be offboarded afterwards.
It is an API call, so it can be part of something bigger.
Opening access does not have to be a person clicking a button. It can be a step inside a support workflow, a diagnostic routine, or something an agent does on its own.
In your own tooling
Raise access from your ticketing system when an engineer picks up a job, and close it when the ticket is resolved. The access window matches the work rather than outliving it.
From an agent
Our MCP server exposes this directly, so an AI agent investigating a fault can open access to the device, look at it, and close it again as part of the same task.
# Illustrative - see API reference for current endpoints
import simsy
client = simsy.Client("your-api-key")
# Ask for a one-off web access link to a device
session = client.open_web_access(sim_id="sim_abc123")
print(session.url) # https://proxy.s-imsy.com/a7f2c...
# Do the work in a browser, then close the door
client.close_web_access(session_id=session.id)When you need in, not when you need a network
Support and fault finding
An engineer picks up a ticket, opens the device, reads the logs, changes a setting, closes it. The whole thing takes minutes and leaves nothing behind.
Third party maintenance
Manufacturers and contractors reaching their own equipment on your sites, without accounts, credentials or a place on your network.
Commissioning
Getting into a device during install to check it came up correctly, from a phone, stood next to it or two hundred miles away.
Occasional estates
Equipment nobody touches for months at a time, where a permanent connection is more risk than it is worth.
Agent driven diagnosis
Automated investigation that opens access, gathers what it needs, and shuts the door behind itself without anyone intervening.
Auditable access
Every session is a deliberate, recorded act rather than a standing permission somebody was granted once and never lost.
SIMSY Proxy is the lightest of three.
All three come from the same thing: you control the network, so you can work the way you would on any network you own. Proxy is the one that needs nothing set up at all.
Devices reaching each other
Put SIMs on a shared private subnet so they can talk directly. Right when the traffic that matters runs between machines rather than back to you.
Your network, extended
Layer 2 handover onto the network you already run, authenticated by your systems and addressed from your pools.
Reach something from your desk.
Put a SIM in a router, open a link to it, and see the router’s own screen in your browser. It takes about as long as reading this page did.