You must not reverse engineering the TCPIP protocol that Packet Engine uses to communicate with client applications. This protocol copyright belongs to me and you cannot emulate it.
You can only use it for writing client applications.
Your program is totally independent from Packet Engine. You can disturb your program any way you like. Freeware, Shareware or as commercial application. Since AGW Packet Engine is self-standing application its license agreement is not applied to your program. However the end user must respect the Packet Engine License agreement.
Packet Engine runs as a standalone program and can handle simultaneously 100 different tncs and 100 different packet applications. When your program starts connects with packet engine and then you can exchange data. The data exchange format is simple and straight and the communication is done with frames. Always you receive a complete frame with its header (which identifies what kind of frame is) and data. The biggest problem I faced, the first time, was the way to establish communication between Packet Engine and the application program. My first approach was using the DDEML (Dynamic Data Exchange Manager) and so far the only supported interface. Later I wrote a helper dll to be used by Visual Basic programmers since Visual Basic hasn't full DDEML support. The brand new Interface now uses Winsock TCPIP. The benefits are many. First of all we use a worldwide standard interface and second this interface allow networking connections. In other words your application can access Packet Engine from different computers.
I give source code examples (in C++) to see what happens and how to build and interpret the frames.Pascal and Java.
You can always ask me to help you and check your code.
How easy is it ?
It is quite easy and in any way far easier than using the serial port to control an external tnc. It is simpler than TNC2 and WA8DED Host mode interface. And even more is faster.
This is the recommended programming interface. It uses TCPIP to exchange Data with Packet applications. How it Works. Packet Engine listens on Port 8000 for incoming TCPIP connections. Your Program must establish a no blocking socket connection with the computer where Packet Engine runs on Port 8000.If your application runs on the same computer with Packet Engine then use as TCPIP address LocalHost(127.0.0.1). After the connection established, starts the data flow bidirectional. The communication is done using frames. Each frame consists of a header and data. The format of each frame depends on the frame kind. But all frames use the same header format. Using a TCPIP Socket connection to communicate with Packet Engine let your program to access packet engine from any computer in a network (LAN or WAN) even from internet. You can download also the file develop.zip.
AgwpePort is a .NET component, modeled similar to the SerialPort component bundled with Visual Studio, used to facilitate TCP/IP communications with the AGWPE software written by George Rossopoulos (SV2AGW). AGWPE is widely accepted in the amateur radio packet software community and is a tool that provides a standard interface between packet radio software and associated hardware.