Timbuktu Pro 32 uses a well-defined UDP Port -- 407 for connection handshaking. Once the UDP connection is established, then Timbuktu Pro uses TCP ports for each of the eight types of Timbuktu sessions.

Timbuktu Pro TCP Ports

Control -	TCP Port 1417
Observe -	TCP Port 1418
Send Files -	TCP Port 1419
Exchange Files -	TCP Port 1420
Chat-	Dynamic TCP Port
Notify-	Dynamic TCP Port
Intercom-	Dynamic TCP and UDP Ports
Ask for Permission-	Dynamic TCP and UDP Ports

These ports are used during access by Guests, Ask for Permission visitors, and Trusted Users with valid user accounts and passwords on Timbuktu Pro hosts. Any or all of these ports can be firewalled to ensure security from unauthorized users. Some network managers will firewall all ports but allow the ability for a connection to be established to UDP Port 407. This allows anyone on the Internet to send files via Timbuktu Pro.

Timbuktu Pro also supports attended access from temporary guests where the host's user admits the guest on a one-time basis without requiring a password. Timbuktu Pro defaults to using a dynamic port assignment for this type of connection thereby bypassing the firewall on the static ports.

Registered port numbers are used only by computers receiving a connection. Users who initiate connections are using dynamic port numbers. A dynamic TCP port is negotiated by the two computers involved in a Timbuktu Pro connection. Dynamic ports usually have numbers greater than Port 1023. If these dynamic ports are firewalled, Timbuktu Pro will not be able to complete a TCP/IP connection.

Solution:
The network manager will need to re-configure the firewall permissions to permit TCP and UDP port assignments. Please refer to our guide on how to connect through a router running network address translation at the following URL:

http://www.netopia.com/support/howtodocs/win/nat.html