Packet Engine Pro Help

General Information
   
Introduction
   Features
   Supported TNCs
   
User Interface
   Registration
   Copyright
Program Setup

   Radio Port Mgr
    . Edit TNC/modem Port
    . Edit Sound Card Port
       - Tuning Aid
       - Volume Settings
    . Edit Parameters
    New Port Setup
    Network TCP/IP Settings
   Radioport Sharing
   
Auto Start Clients
   Other Settings
Views
   Program Status
   Port Activity Status
   Shared Radio Ports
   AX.25 Status (Stations)
   Connected Programs
   Heard Stations List 
   Monitor
Other Features
   TCP/IP Over Radio
     . Driver Install
     . PE Pro Settings
     . Windows Settings
   Registration
   HTTP Interface
   Live Update
   Launch IE Browser
   Go to AGWsoft web site
   Send Error Report
Tips, Tricks, & Trouble
   Tips and Tricks
   Problems?
   
Sound Card Use
     . Sound Card Interface
     . HF Operations
     . 9600 Operations
     . Receive Problems
     . Transmit Problems

 

Help Date: 21 June 2004

 

 

Network TCP/IP Settings

Network Settings
Network Security
Network Routing Issues

Packet Engine Pro uses the Winsock TCP/IP Interface to communicate with most application programs, although it can also use the less robust DDE interface.

Network Settings

By default, the Winsock interface is activated and the Network Settings screen should look like the picture below. The Enable Network TCP/IP Application Interface box should be checked and the TCP Port should be set to 8000.

There should be hardly little reason to disable the Winsock interface. If you encounter error messages saying your application program could not connect to PE Pro, be sure the interface is enabled/ check-marked.

The TCP port setting of 8000 is an arbitrary setting chosen to avoid port conflicts with other applications. You should only change this is you suspect some other application has already using port 8000. If you do change the port number, you must configure any application programs using PE Pro to use the new port number you have chosen.

Note that the TCP/IP protocol makes it possible for packet applications running on other computers to connect to your instance of PE Pro over a network (LAN or Internet). To do this, the application program must be configured to specify the IP address of the PE Pro computer and Network TCP/IP Application Interface port number (8000 by default). Not all applications can do this, however.
 

Network Security

To control remote access to PE Pro's Network TCP/IP Application Interface (port 8000,  you can adjust the settings on the Network Security screen. By default, PE Pro lets only applications running on your computer connect to port 8000 without providing a username and password (button #3).

If you wish, can permit other unsecured connections to PE Pro:

  • button #2 allows unsecured application connections from your computer plus any computer in your local area network (LAN). Applications outside the LAN can only get access with a login name and password.
  • button #1 allows unsecured connections from applications on any computer anywhere; no login name or password required.

If you opt for the restrictions of option #3 or #2 , you can still give users in remote locations secured access to PE Pro by adding their login name and password to an exceptions list (under User Setup). Press the New User button to add an arbitrary Login (user name) and Password.

In the picture above, setting #2 has been selected, so any computer in the LAN can access this version of PE Pro (internet users can not). In addition, anyone using the login name of SV2AGW and a password of 4x77k will have access even if they are outside the LAN.

Note that for PE Pro's secured (Login/Password) access to work, your application program must be able to send the Login and Password to PE Pro. Few programs can do this. Even the other AGW Software programs (AGWTerm, etc.) have no provision for sending Login/Password information. As of June 2004, only UI-View32 was known to be able to do this (UI-View automatically sends your callsign as your Login name; you tell UI-View what to send for a password).

Warning: If you let remote users have access to your instance of PE Proports, then they can both send and receive packets using your equipment. In most countries, you are still responsible for anything your station transmits even if someone else is initiating the transmission!

To control use of your equipment:

  1. Don't permit unsecured use of your PE Pro (button #1). If you must use this option, do not make public your IP address.
  2. Use the Login/Password feature for trusted users, although this feature will not work if the users are not using an application that can send the login/password (only UI-View32 does)
  3. Use the Monitor view to watch what PE Pro and your equipment are transmitting.
  4. Consider disabling your radio's PTT circuit so that PE Pro does not transmit, i.e. users can only receive and not transmit. (Many radios have a Lock button to disable the PTT. Or if you are using a sound card modem, set it for "RX only" or disconnect the PTT interface cable from the computer's serial/LPT port.)
  5. Experiment with your firewall program to see if it can limit access to the IP addresses of trusted users only.

 

Networking Routing Issues

  • "Other computers on my LAN" --  PE Pro defines "other computers on my LAN" as other computers whose IP address has the same first three octets as the PE Pro computer. Example, if the PE Pro computer has an IP address of 192.162.0.101, then other computers with an IP address beginning with 192.168.0. are considered part of the LAN. (Same as having a sub-net mask of 255.255.255.000

    Note: Even though computers on different networks may have the same local IP address, say 192.168.0.101, they will not be seen as being part of your LAN. Here is why. When you communicate over the internet, your computer's network communication device (router, data modem) uses Network Address Translation (NAT) to replace a.) your local IP address with b.) the router/data modem's unique network address as assigned by your Internet Service Provider. By protocol definition, network addresses do not use the same beginning numbers reserved for private networks (private addresses begin with 192.x.x.x or 10.x.x.x.)    Example: Your computer has a private, local IP address of 192.162.0.101, however, when communicating over the internet, your data modem uses NAT to substitute its unique network address, say 24.124.49.109, for your computer's local IP address. A distant computer will see only your modem's network address, not your computer's private address. When the data you requested comes back to your modem, the modem uses NAT to reverse the substitution so that the data goes to your computer. In sum, private local addresses are never used to communicate over the internet, so a remote computer will never be seen as port of your LAN.
     
  • Firewalls: Firewall programs (example Zone Alarm) and hardware devices (routers) by default are configured to block messages from remote computers unless they match specific IP addresses and/or ports (or unless your computer initiated the request). If you are having difficulty with a remote computer accessing your PE Pro, it could be because of a firewall issue. To test this, turn off the firewall at both locations.

    To correct a firewall blocking issue at your end, you must configure the firewall program or device to allow data requests for port 8000 (default) and route them to the PE Pro computer. Read your software/hardware's manual to find out how to do this. (It may be listed under "Virtual Server"). Programs such as Zone Alarm may also restrict your computer's programs from sending out responses to information requests from remote programs. Again, you will have to read the firewall program's documentation to learn how to designate PE Pro act as a server that is permitted to send information outside the LAN.
     
  • How to specify the remote IP Address of the PE Pro Computer: If remote users want to connect to your PE Pro computer, they must specify the network address assigned to your data modem by your ISP (internet service provider) or internet proxy server. They would not specify your computer's local IP address.  If  you have an arrangement with your ISP for a static network address (usually a more expensive option), then your network address will not change. If you are a dial-up customer, proxy user, or have a DSL/cable dynamic (changing) connection, your network address may change with each new connection. Remote users would then have the problem of knowing your currently assigned network address.

    One way to learn your network address is to send yourself an email. When the email comes back to you, look in the expanded message headers to see the address your ISP used to forward the mail to you. Also, some web sites will tell you what it is. Do a web search for "What is my IP address?" to find such sites.
     
  • Dynamic IP Address? Here's work-around for you to consider if you have a dynamic IP address, but want to provide remote users with a fixed address:
  • First, obtain a personal domain name (for about USD $35/year). Example: www.sv2agw.org
  • Then, find a dynamic DNS (domain name system) service that will match your current dynamic IP address with your domain name. This is done by running a utility on your computer that periodically contacts the DNS service to tell it your current network IP address. With this setup, users can then just enter your personal domain name to connect to you; they need not worry about entering your actual network IP address. The dynamic DNS service will make the translation.

    To find a dynamic service provider, do a web search for "dynamic DNS". Some offer free services or free services if you buy your domain name from them.

Copyright 2004 SV2AGW George Rossopoulos . All rights reserved.