As mentioned in the Preface, the Flash Communication Server uses a proprietary protocol, RTMP. This protocol is used to transfer data and messages between Flash Player 6 and the Communication Server. This protocol does not interact with the web server protocol, HTTP. Most web servers run (by default) on ports 80, 81, or 8080. Microsoft web server ports are set up in the IIS Manager, where the IP Address is set. Knowing what port your web server is communicating on will ensure that you do not set the Communication Server to use the same ports.
The Communication Server uses two ports in its operation:
Admin Port (default: 1111). Used by the management consoles to monitor and control the server remotely. This is an important port to keep private, especially on production servers. Access to the administration controls allows a user to halt or restart the server or interrupt applications. You don't want unauthorized users to have access to these areas. There will be more discussion on blocking access to the server administration in Chapter 13, "Accessing External Data."
Server port (default: 1935). This is used by the server to maintain persistent connections with Flash Player 6 and other Flash Communication Servers. If you change this port number, your Flash movie must include the port number in the connection string. Firewalls may pose a problem if these ports are blocked. Your network administrator can allow communication through these ports or assign you ports you can use. If you have a personal firewall, make sure you open the ports you plan to use. Only the application port (1935) needs to be accessed. Port 1111 can be limited to a local connection or connected within your virtual private network (VPN). Disabling the 1935 port will restrict connections outside your network from accessing the Flash Communication Server. If you are using the server as a development server, on your localhost (your workstation), you do not need to worry about firewalls.
Both of these ports have been assigned to the Flash Communication Server by the Internet Assigned Numbers Authority (IANA). For more information on this group, visit http://www.iana.org.