Copyright: Copyright (c) 2000-2002 of TORDIVEL AS. All rights reserved


Introduction

Note: Internet Messenger 4.5 is the same component as Internet Messenger 4.0, except that licencing is removed, and that the control will not be visible when printing a web page containing the control.

Internet Messenger is an ActiveX component combining the best of Windows NT and TCP/IP. This means that anyone can build real internet applications based on any 32 bit Windows development tool.

This is a component you can use to quickly make your application net-aware, able to communicate across your LAN, WAN, or the Internet. Internet Messenger will transmit text-based messages between applications, addressed by an ip-address/port number combination. Internet Messenger guarantees delivery of all messages, notifying your application when the message has been received. (Of course, if the network is down, the message can not be delivered, in which case your application will receive an error notification). Any number of messages can be queued for transmission - the Internet Messenger provides a true non-blocking transmission. In addition, messages sent to a single receiver are guaranteed to be received in order.

The InternetMessenger is a part of the TORDIVEL SOFTWARE SOLUTIONS.

InternetMessenger is copyright of TORDIVEL AS 2001-2002.

27. June 2002, Oslo, Norway.

Help Index

•	The Package

•	ActiveX Interface

•	Using the TInternetMessenger program

•	Network protocol


The Package

The package consists of

•	Internet Messenger 4.5 ActiveX Control

•	TInternetMessenger 4.5 – a test terminal for Internet Messenger

•	Internet Messenger 4.5 Help file


ActiveX Interface

To use Internet Messenger in your application, simply insert an Internet Messenger ActiveX control in a dialog (or form). Your GUI tool will provide you with a list of properties and events for the control, but here is a summary:

Properties

•	Timeout - maximum time Internet Messenger will wait for a message to be acknowledged, before the message is deemed lost

•	RemoteComputerAndPortName - who we talk to. The syntax is "computer:port", e.g., "localhost:7701" or "127.0.0.1:7701". DNS lookup is automatic.

•	LocalComputerAndPortName - who we are (also, which port we listen to). This information is sent with each message, identifying the sender. Note: you can leave the ComputerName part blank, as in “:7701” (the colon must be present!), in which case your current IP address will automatically be used.

•	QueueSizeThreshold - receive warnings if more than this number of messages are queued to a single receiver

Methods

•	Send - send a message. Any text will be sent to the receiver specified in the RemoteComputerAndPortName property.

•	AboutBox - show About

•	CanReceive - are we really listening at the moment?

•	GetQueueSize - find how many messages are queued to a specific receiver at any moment

Events

•	Receive - a message has been received

•	MessageError - we couldn't send a message, most likely due to network errors

•	MessageAck - message has been sent (and received)

•	QueueSize - the number of messages queued to a single receiver has exceeded the threshold

This narrow interface should make you able to quickly be up and running. Simply set the properties you want and start sending messages!  You are of course free to ignore any events, if you do not want them.


Using the TInternetMessenger program

This test program exposes the complete Internet Messenger interface, in an easy-to-use dialog-based application. You can control and test all aspects of Internet Messenger using this program.

Message String

Interatively write and send a message to the remote computer

Statistics

Relevant message statistics are presented.

Test

Check boxes to enable autosend and echoing all received messages

Connection

Defines the tcpip-adresses and portnumber of Me ( this TInternetMessenger terminal ) and the remote terminal. The CanReceive checkbox shows if this terminal successfully has opened the configured portnumber ( Me ).


Network Protocol

The Internet Messenger 4.5 Network Protocol is pure text with the following properties:

•	No restriction on message size

•	A message has the following format :

•	Header – format is <ip>:<port>:

•	zero-terminated ascii string

•	Each message is acknowledge by sending a lf-character to the client in the open socket

Procedure to send a message to a Internet Messenger server:

1.	Open a socket

2.	Format Header with requester 193.69.239.12:80:

3.	Concat the header and the zero-terminated message string    “193.69.239.12:80:Hello<null>”

4.	Send the package over the open socket

5.	Wait for an acknowledge

6.	Close the socket.

The ip–format is 193.69.239.10.


TORDIVEL SOFTWARE SOLUTIONS

TORDIVEL AS Software House is developing a portfolio of Windows NT/2000 software components and solutions with the following properties:

•	simple and easy to use

•	very high quality

•	requirements from real use cases

•	easy to deploy

•	"simply working"

•	network applications building blocks

Important keywords are: HTTP, TCP/IP, XML, and stateless servers.

These components and solutions are divided into two categories:

•	Professional Software Components

•	Freeware Components Library

We distribute the components and solutions to promote the skills of the experienced developers working at TORDIVEL and want to establish links to developers and companies all over the world.

If you have comments/suggestions your feedback is more than appreciated. Please contact us.

Storgata 20 N-0184 OSLO NORWAY
Telefax +47 2315 8701 Telephone +47 2315 8700
E-mail: office@tordivel.com Web: http://www.tordivel.com


Copyright Notice

(c) 2001-2002 Internet Messenger is copyright of

Storgata 20 N-0184 OSLO NORWAY
Telefax +47 2315 8701 Telephone +47 2315 8700
E-mail: office@tordivel.com Web: http://www.tordivel.com