1. Utilizing Military Message Handling Systems as a Transport Mechanism for SOA in Military Tactical Networks
Mr Frank T. Johnsen,
Mr Anders Eggen,
Ms Trude Hafsøe, and
Dr Ketil Lund

2. Outline SOA, Web services and NEC Web services and tactical networks
HTTP and TCP
STANAG 4406
Experiment setup
Results

3. SOA, Web services and NEC
The first step towards NEC is to integrate legacy strategic and tactical systems into a common network.
Each legacy system can be viewed as a separate module that needs to be interconnected with others.
The modular concept from Service Oriented Architectures (SOA) is essential.
Cooperation between modules requires a common standardized means of communication between them.
Web services
The challenge lies in using Web services over tactical communication systems with low available bandwidth and high error rates, so-called disadvantaged grids.

4. Web services and tactical networks
Data-rate constraints in tactical networks impose great challenges that have to be solved in order to fully deploy a SOA supporting NEC.
In our previous work we have suggested the use of various techniques to limit bandwidth usage, such as
compression,
filtering,
and proxy servers
On the Internet, Web services use the XML-based SOAP protocol over HTTP and TCP for information exchange.
The properties of HTTP/TCP make them unsuited for use in disadvantaged grids.

5. HTTP and TCP Web services on the Internet SOAP over HTTP over TCP
TCP connections break in disruptive networks.
timeouts
unstable connections
The synchronous nature of HTTP/TCP is undesirable in disadvantaged grids.

6. Replacing HTTP/TCP
Disadvantaged grids require asynchronous communications and protocols that are able to cope with the characteristics of such networks:
Data rate and delay issues
Protocols should withstand long and variable round trip times, while at the same time having very little communication overhead.
Disconnection and disruption issues
Store and forward capabilities
The traffic in NEC will have to traverse heterogeneous networks with different quality and data rate – this requires a store and forward service.
Our suggestion is that one should consider replacing HTTP/TCP with the Military Message Handling System (MMHS) implementing STANAG 4406.

7. STANAG 4406
In NATO, Formal Military Messaging is standardized in STANAG 4406 ed. 2 (S4406).
S4406 defines three protocol profiles adapted to different communication networks.
The original connection oriented protocol stack defined in S4406 Annex C was developed for strategic high data rate networks.
The protocol profiles TMI-1 and TMI-4 have been developed for use between Message Transfer Agents (MTAs) over disadvantaged grids.
With the inclusion of these protocol profiles in Annex E of S4406, a common baseline protocol solution exists that opens for the use of MMHS in both the strategic and tactical environments.
In addition to military messaging, MMHS may also be used as an infrastructure for interconnection of other applications.

8. Benefits of MMHS
The benefits of using MMHS can be summarized as follows:
Reuse of an already established messaging infrastructure in NATO and the NATO nations.
Three different protocol profiles that enable tailoring of the transport system to the communication networks.
Support for both reliable and unreliable transmission modes.
Asynchronous store and forward system.
Support for priority and preemption mechanisms.
Support for both multicast and unicast of messages.
We have experimented with MMHS as a carrier for SOAP, replacing HTTP and TCP.

9. Experiment setup
We SOA-enabled an experimental tactical system, the Norwegian Modular Network Soldier (NORMANS).
We wrapped the NORMANS software in a Web service, using standardized XML-encoded NFFI.
Communication took place over a low bandwidth network, in our case 2.4 Kbps.
We used the NIST Net network emulator package for emulating a tactical link in our experiments.
Optimizations
XML compression (EFX)
MMHS / STANAG 4406
A local HQ built and visualized a common operational picture with aggregated information from several sources and communication partners.
Content filtering

10. Experiment setup Tactical network (Communication over S4406) Local HQ
(FFI Node)
NORMANS Advanced
Tactical network
(Communication
over S4406)

11. Tactical network, e.g., 2.4kb/s1
Tracks from NC3A and NORCCIS-II distributed to NORMANS and FFI node
Track is decompressed and translated to NORMANS format
Track is sent to NORMANS (over a simulated disadvantaged grid)
Track is translated to internal FFI format and stored in track store
Track is compressed using EFX
Translator
EFX
EFX
Translator
Translator
SOAP over tactical MMHS
Track is translated to NFFI
Translator
Tactical network, e.g., 2.4kb/s
NORMANS Advanced
Track is translated to MARIA format
SOAP over HTTP
MARIA
NFFI
Internal FFI format
Bygge opp felles situasjonsbilde
Utveksler tracks, fra stridsteknisk, opp til ”strategisk” nivå vha Web Services (som er en måte å realisere SOA på)
Håndterer diverse formater, NFFI er hovedformatet for ekstern datautveksling
Visualisering med MARIA
Mot N-II og NC3A: vanlig WS
Mot NORMANS: SOAP over XOmail, over simulert taktisk nett
komprimering med EFX
Track is sent to MARIA (locally)
MARIA-format
NORMANS-format
NORCCIS-II sends NFFI-track to FFI node
FFI node
SOAP over HTTP
NC3A sends NFFI-track to NORCCIS-II
NORMANS: Norwegian Modular Arctic Network Soldier NORCCIS: Norwegian C2IS
NC3A
NORCCIS-II

12. Experiment setup
We transferred documents containing NFFI-tracks, and we compressed the documents using efficient XML with built-in compression enabled.
We compared the two tactical profiles of S4406, TMI-1 and TMI-4, in order to establish the efficiency of the two profiles.
Theoretically, TMI-1 should incur higher overhead than TMI-4, as shown below

13. Results The documents sent to HQ contained one NFFI-track.
The documents sent from HQ to NORMANS Advanced contained 20 to 25 NFFI-tracks each.
Thus, the graph clearly shows the effect of compression; sending 20 tracks only takes about twice the time of sending one track.
When comparing the bars for TMI (TMI-1) and DMP (TMI-4), it is also clear that TMI has considerably more overhead than DMP.
DMP has less overhead because it does not implement full support for all MMHS features.

14. Summary
MMHS has many of the qualities that are needed to ensure delivery of messages between strategic and tactical communication systems, and gives the benefit of being able to reuse an existing infrastructure for a new purpose.
low overhead
store and forward

15. Summary Through our experiments we have shown that
MMHS can be used as a replacement carrier for Web services.
MMHS avoids the time-out problems that arise when using standard HTTP over TCP in tactical networks.
an existing (proprietary) service can be adapted to a SOA environment; and that by taking the necessary measures, Web services can be used in disadvantaged grids similar to the one we emulated.
Specialized protocol profiles are needed, and we have concluded that both TMI-1 and TMI-4 can be used in this scenario.