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Warfighters May Chat With Confidence

November 2010
By Maryann Lawlor, SIGNAL Magazine
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While taking part in an emergency response exercise, Col. Janice Dombi, USA, deputy commander, U.S. Army Corps of Engineers, South Pacific Division, works in a deployable tactical operations center (TOC) trailer. Distributed chat systems would enable network managers within military as well as first-responder TOCs to maintain communications about systems activities even when connectivity is lost.

Combination of commercial solutions delivers dependable connectivity at the tactical edge.

Members of a tactical operations center soon may be able to count on chatting as a reliable means of second-to-second communications with each other and those in other centers. As part of a Small Business Innovation Research project, the Space and Naval Warfare Center–Pacific is exploring readily available commercial solutions that would enable numerous centers’ members to keep up to date even after systems go down. If fielded, the system also would increase bandwidth usage efficiency and communications dependability.

Research into the capability is being conducted as part of the larger Joint Tactical Radio System (JTRS) program. The most recent development includes the move to the second phase of a contract with CoCo Communications Corporation, Seattle, and comprises continued research and new testing of a distributed chat capability.

According to Dale Bryan, radio frequency communications and network engineer, Space and Naval Warfare Systems Center–Pacific (SSC-Pacific), the JTRS Network Enterprise Domain program has been focusing on a number of ways to improve the way warfighters communicate. These include developing software waveforms that operate on platforms such as ground mobile radio; handheld, manpack and small form-fit radios; and airborne and maritime/fixed-site radios.

Coordination of so many different types of radio systems can be challenging, so the JTRS Wideband Network Manager (JWNM) team was searching for a reliable chat capability that could help communications managers within tactical operations centers (TOCs) continually stay in touch, share information and assist each other when necessary. These managers coordinate network activities such as conveying problems they see in their own networks, informing others about what network changes they plan to make and collaborating to improve efficiencies.

Bryan explains that his group also was in search of a solution to the problem of what happens when the connection among TOC network managers goes down and conversations are lost midstream. TOC network managers already have been using chat capabilities; however, they cannot depend on chat because lost connections interrupt the flow of important communications, Bryan explains.

Under the Small Business Innovation Research program, the SSC-Pacific awarded a contract to CoCo Communications to determine how to take the multicasting approach—which has not been extremely reliable—and find a better way to send messages to multiple locations. The trick was to ensure that the technique would be reliable in an environment where communications links are undependable or changing constantly.

Jeff Meyer, vice president of product management, CoCo Communications, explains that his company has been pulling together effective and readily available solutions to address the SSC-Pacific’s problems. First, the company’s team chose to use the Openfire server, a real-time collaboration service licensed under the Open Source General Public License. Openfire uses extensible messaging and presence protocol (XMPP), the widely adopted open protocol for instant messaging. Server-to-server communications are based on XMPP messages being reliably multicast using Negative Acknowledgment Oriented Reliable Multicast (NORM) messaging across the wideband networking waveform network cloud. The Naval Research Laboratory developed NORM. According to Meyer, the technique addresses the problems that past systems pose because they are highly sensitive to changes in network reliability and do not work well even in moderate packet loss environments.

The company also chose to implement a highly distributed server deployment. Each TOC’s enclave can have its own or multiple servers to improve the resilience of the overall chat system, he explains. Clients are connected to the servers using standard XMPP protocols. This enables them to use a variety of standard products, including Pidgin, a chat program that allows them to log in simultaneously to accounts on multiple chat networks.

“Network splits often cause users to have different views of the same conversation. The CoCo Communications’ solution correctly merges all disparate views when enclaves reconnect, and highlights the missed content for quick and easy identification. Traditional solutions are unresponsive to this common tactical problem,” Meyer states. Recognizing that it had to deal with the problems posed by servers located in multiple places, CoCo Communications connected servers using the reliable NORM protocol, then added the presence features. It also changed some of the technologies related to chat and used its knowledge of mobile networks to implement features such as message replay, he adds.

To address the issues of presence detection and message replay, the CoCo team chose to put the mobile networking into the application space, which prompts it not only to check constantly if a user is connected but also to confirm that the user is on the chat network. Because of existing network architectures, legacy chat systems often are fooled into thinking users are connected when they are not, Meyer explains.

When connections between network managers are lost however, the next problem is ensuring that when they re-enter the chat they can both participate in it again, as well as see the conversations that took place while they were offline. One of the challenges of this capability is to avoid clogging the airwaves by sending a burst of messages simultaneously to the reconnected network managers. CoCo Communications solved this issue by invoking a compression feature that ensures that bandwidth is used efficiently.

The company relied on its experience in creating self-forming networks. It has worked with organizations such as the U.S. Coast Guard to create shipboarding team communications systems. Multiple mesh networks are set up rapidly, and the wireless ad hoc mesh network eliminates traditional below-the-decks connectivity problems and continues to keep security personnel connected even in locations where ultrahigh frequency/very high frequency radios do not operate.

The overall topology of the SCC-Pacific solution offers the JWNM a number of benefits. In addition to portraying participant presence accurately and facilitating wise bandwidth usage, distributing the servers means that a failure at a single point does not cause an overall failure of the chat capability within a TOC or among centers, a feature that also boosts security.

Currently, research and testing of this chat feature relates only to text communications that that are XMPP-based. However, Meyer points out that no technical reason exists that this standard could not be used in other areas such as voice as well. The company currently is working on these types of advanced capabilities, he reveals.

Bryan allows that at this point information security is not a concern because the identities of users on the TOC workstations all have been authenticated through normal military information assurance processes, and that the radios being used are Type 1 encryption certified. The next step will be to examine how to encrypt data as it crosses the network, which will increase security, he adds.

At the awarding of the follow-on contract to CoCo Communications late this summer, the SCC-Pacific team and the company began the testing and experimentation phase to compare this approach to the capabilities the current architecture offers. The work is taking place at the JWNM laboratory. Plans also include bringing the distributed chat program to the field, so soldiers at Fort Huachuca, Arizona, could use the system and provide their feedback, which would be incorporated into the company’s solution.

According to Meyer and Bryan, the challenge for both organizations is moving from the laboratory to the field. The company believes this capability not only would benefit the military but also has big implications in areas such as in public safety organizations. In situations where first responders from numerous organizations arrive on the scene of an emergency and set up their own operations centers, the distributed chat program could facilitate coordination of network managers’ activities. However, moving in this direction is a matter of making a broader audience aware of the benefits of this solution.

From the military perspective, Bryan admits that the acquisition process could slow down introduction of the solution into current operations. Once it passes the acquisition process, the capability could be in the hands of TOC network managers in a matter of months, he predicts.

WEB RESOURCES
JTRS Network Enterprise Domain: www.public.navy.mil/jpeojtrs/pages/NED.aspx
CoCo Communications Corporation: www.cococorp.com
Openfire: www.igniterealtime.org/projects/openfire
Pidgin: www.pidgin.im