> ## Documentation Index
> Fetch the complete documentation index at: https://developers.telnyx.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Beta Limitations

> What the Tailscale Subnet Router beta does not do yet.

The Tailscale Subnet Router is in beta, with these limits.

## No Site-to-Site Networking

Flows start only on the tailnet. [Site-to-site networking](https://tailscale.com/docs/features/site-to-site), where hosts on the [*Network*](/docs/network/overview) also start flows toward the tailnet, is not available.

## Functions Are Reached by Address

The *Network* has no DNS. A function is reached by its address, and each deploy moves it to a new one. The old address stops answering when the deploy completes, and the new one answers within about a minute. Look the address up again after each deploy, as in the [Quick Start](/docs/network/tailscale-subnet-router/quick-start#find-the-address).

## Functions Cannot Be Private

A function with a network binding keeps its public URL. It answers there and on the *Network*.

## One Site, One Revision

A function with a network binding runs at one site, with one revision on the *Network* at a time.

## Always Running

A function with a network binding runs one instance at all times. It does not scale to zero, because requests over the *Network* cannot wake a stopped function.

## Every Open Port Is Reachable

The *Network* has no firewall. Every port a function opens is reachable from the *Network*, and from the devices behind the router that the tailnet policy allows.