Magic Wand

DIS PDU Router for Windows

What is DIS PDU Router?

PDU Router is a PC Windows based application that provides powerful DIS filtering capabilities in a LAN to WAN connection environment to significantly reduce bandwidth requirements The application consists of two parts, the Master Unit and an optional freely distributable remote Slave Unit that is controlled from the Master Unit to provide filtering at the remote end of the WAN.

Another benefit of using the PDU Router is that it isolates the IP/Port Number addresses being used on the LAN from the WAN, and avoids complex IP Address modifications to accommodate different WAN configurations. For example, it is not unusual to have a simulator and associated DIS Radio equipment comprise 20+ individual items of hardware, each with their own IP and Port Number address allocation. If participation in a Wide Area Network simulation session requires IP address/port number combination that is different to the normal settings, instead of having to modify 20+ node IPs and Port Numbers, only a single dialog box option change is required.


What kind of Filtering does PDU Router Provide?

PDU Router provides six level hierarchical filtering. All filtering is specified in the form of what PDUs to accept for routing from the LAN to the WAN, thereby automatically filtering any unwanted PDUs. Filtering is provided for:

  1. Exercise ID: PDU Router will only route PDUs matching the specified Exercise ID's, with an option for All Exercise ID's.
  2. DIS Family: PDU Router will only route PDUs belonging to the specified DIS Families, with an option for All Families.
  3. Site/Application: PDU Router will only route PDUs from specified Site/Applications, with an option for All Site/Applications. Up to 64 Site/Applications may be specified.
  4. Entity Range from Datum: PDU Router will only route PDUs (Entity State PDUs and any equipment associated with a platform) that are within a specified number of Nautical Miles from a specified Datum point Latitude/Longitude. An option is also provided to accept entities regardless of Range.
  5. Platform Domain: PDU Router will only route PDUs (Entity State PDUs and any equipment associated with a platform) that match the specified Domain (Land/Air/Surface/Subsurface/Space and undefined domains up to the maximum value of 255). No option is provided for All Domains, rather each individual domain must be enabled separately.
  6. Radio Frequencies: PDU Router will only route PDUs for transmitters operating within one of up to 32 specified frequency ranges, with an option to route all frequencies.

Additionally, PDU Router provides options to unconditionally not route any Radio Receiver PDUs and/or any Intercom Control/Signal PDUs.

What sort of Bandwidth Savings are to be Expected?

The actual bandwidth savings that will be achieved depends very much on the configuration for a particular DIS exercise. In particular, the major savings that are usually achieved is the filtering of local intercom traffic that is not required to be transmitted on the WAN. The actual savings of course depend on the number of local intercom circuits that are available to be filtered, and the amount of DIS traffic that those intercom circuits are generating.

As an example, on the 25th of October 2001, the USN BFTT and the Australian Navy's HMAS WATSON training site carried out a dress rehearsal for the upcoming I/ITSEC coalition joint training demonstration. Using the Redsim DIS PDU Router to filter only the local intercom traffic on the Australian LAN, the following figures were obtained when applied to a five minute recording made during the exercise.

Measurement Unfiltered traffic on LAN Filtered traffic on WAN
PDU per second 63.04 26.71
Average Mbit/sec 0.1491 0.0841
Peak Mbit/sec 0.4530 0.2660

As may be seen from the figures above, a reduction of 41% in the peak per second bandwidth and a 43% reduction in the average per second bandwidth utilization was achieved in the example quoted. These figures are fairly typical, and it is not unusual to achieve a bandwidth reduction of the order of 40%.

What about Latency?

PDU Router introduces minimal additional latency. Typical latency values are of the order of 10ms, but of course the actual value depends on the level of congestion on the WAN.

How Complex is the Setup Procedure?

The setup procedure is a simple matter of ticking the appropriate check box or typing in values when prompted by the software. Once a set of filter options have been specified, the current options may be saved to a file for easy recall at a future date.

What about Controlling the Slave Unit?

Control of the Slave Unit is fully automatic. Whatever filter options are specified for the Master Unit, are automatically transmitted to the Slave Unit within 5 seconds. The Slave unit may not be configured at the remote site, as it always takes it's filter settings from the Master unit.

How is the Communication with the Slave Performed?

Communication between the master and the slave units is via the WAN DIS IP Address/Port Number, using a non standard DIS PDU of Type 199 Family 199 transmitted with an Exercise ID of 199.

Is Use of the Slave Unit Compulsory?

No. The Master Unit may be used without the Slave if it is only desired to filter the PDUs from the 'local' LAN to the WAN. The Slave unit is provided to optionally allow filtering to be controlled at the 'remote' end of the WAN. While the Master Unit is a licensed product, the Slave Unit is an unlicensed product that may be freely distributed by the owner of the Master Unit. As long as the remote site can provide a simple PC to host the Slave Unit, remote filtering is achieved.

What Platform does PDU Router Require?

The PDU Router will run on any standard PC running Windows 7 or later.