8.7.2.3   HOSTS file for mixed Private and Public Users

Before modifying the Host files, try using the Address Mapping in section 8.7.1.2.  These are similar features, but the Host  file is built into Windows.

Here is how to use the HOSTS file to force different addresses to be used by Internal  Private Intranet Users and External Public Internet user. This is usually done on the Clients to allow external clients to connect to a Private Network or to hide the SCADA node and/or Project Node IP Addresses or port numbers.

This makes for a more secure system by requiring clients to modify the Host file.  The actual IP addresses of the SCADA Nodes and Project Nodes are hidden from outsiders.  

1.      Pick a single "valid" name that works for all possible network connections (IP, Novell Network Name, Microsoft Network Net BIOS Name).   No spaces!

In the example below it is PROJECTSCADA 

If you use can a Network Name (the Microsoft Net Bios Name), then internal users, the SCADA Node and Project node can be configured to use this name (with out creating the HOSTS file below) and only the external Clients will need the modified HOSTS file.

2.      Modify the  HOST File for external users to  use the same HOST name or Network Name the internal users can use. Further, this name should be a network or host name that the Project Node Software can use to contact the SCADA Node software.

HOST file for external users connecting with Public IP Address.

 C:\WINNT\system32\drivers\etc\hosts

 

# Copyright (c) 1993-1999 Microsoft Corp.

#

# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.

#

# This file contains the mappings of IP addresses to host names. Each

# entry should be kept on an individual line. The IP address should

# be placed in the first column followed by the corresponding host name.

# The IP address and the host name should be separated by at least one

# space.

#

# Additionally, comments (such as these) may be inserted on individual

# lines or following the machine name denoted by a '#' symbol.

#

# For example:

#

#      102.54.94.97     rhino.acme.com          # source server

#       38.25.63.10     x.acme.com              # x client host

 

127.0.0.1       localhost

67.94.27.179  PROJECTSCADA

 Note 64.55.156.4 is an example of a Public IP Address

HOST file for internal  users, SCADA Node and Project Node connecting with Private IP Address (if Network name can not be used internally)

 

C:\WINNT\system32\drivers\etc\hosts

 

# Copyright (c) 1993-1999 Microsoft Corp.

#

# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.

#

# This file contains the mappings of IP addresses to host names. Each

# entry should be kept on an individual line. The IP address should

# be placed in the first column followed by the corresponding host name.

# The IP address and the host name should be separated by at least one

# space.

#

# Additionally, comments (such as these) may be inserted on individual

# lines or following the machine name denoted by a '#' symbol.

#

# For example:

#

#      102.54.94.97     rhino.acme.com          # source server

#       38.25.63.10     x.acme.com              # x client host

 

127.0.0.1       localhost

192.168.0.12   PROJECTSCADA

 

3.      Use UPDATE  in Project Manager

a.      Change the Network Name of Project Node (IP Address Field) to PROJECTSCADA

b.      Change the Network Name of SCADA Node (IP Address Field) to PROJECTSCADA

4.      Download your SCADA Nodes.