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BILLETKnowledge Base

Direct and relayed connections

When a session goes straight between a person's computer and the host, when it goes through the relay, and the settings and ports that decide it.

For
Administrators
Applies to
Billet 1.0
Updated

Every session's picture, sound and input travel one of two ways:

Direct Relayed
Path The person's computer dials the host Both ends dial out to your relay, which joins them
Host needs Inbound UDP 4455 reachable from the person's computer Nothing inbound
Works Where the two can reach each other, such as the same office network or a host with a public address From anywhere both ends can reach the relay

The portal decides which to use for each session, from the tenant's settings and what each end can reach.

The settings

In the console, open Settings for the tenant and find Direct connections:

  • Between a person's device and their desktop: choose Allow direct connections, or Send everything through the relay.
  • Local network addresses: Offer local network addresses tells each end the other's address on its own network, so two machines in the same office can connect directly. Stop offering local addresses keeps those addresses private.

A change reaches each person's next session, not one that is already open.

To find out whether one machine can be reached directly, use Test connection on its page with Connect directly, not through the relay. See Test a connection yourself.

Ports on the host

Billet Host listens for direct connections on UDP 4455, and its installer adds a Windows Firewall rule for that port, for the host agent program only. If you send everything through the relay, nothing needs to reach that port, and you can block it at your network firewall.

A host behind NAT

A host knows its own addresses, but not a public address that a NAT router puts in front of it. To allow direct connections from outside to such a host:

  1. Forward UDP 4455 on the public address to the host.
  2. Tell the host its public address, with the installer's Address clients dial for direct connections box, or /ADVERTISE= on the command line. See Install hosts without prompts.

Without these, people outside connect through the relay, which needs neither.