Defense Advanced Research Projects AgencyTagged Content List

Communications and Networks

All manner of sending, receiving, connecting and protecting information

Showing 45 results for Communications + Networking RSS
In areas lacking trustworthy communications infrastructure, deployed servicemembers rely on wireless devices to perform double duty: they not only provide access to the network; they are the network. Protocols for these networks require nodes to coordinate among themselves to manage resources, such as spectrum and power, and determine the best configurations to enable sharing of information. A problem with these protocols is that they implicitly trust all information shared about the security and operational state of each node, and the network as a whole. Consequently, inaccurate control or security information can quickly render the network unusable. This shortcoming could put productivity and mission success at risk as use of military wireless systems increases.
Troops operating in forward locations without telecommunication infrastructure often rely on a mobile ad hoc network (MANET) to communicate and share data. The communication devices troops use on foot or in vehicles double as nodes on the mobile network. A constraint with current MANETs is they can only scale to around 50 nodes before network services become ineffective. For the past 20 years, researchers have unsuccessfully used Internet-based concepts in attempts to significantly scale MANETs.
Air-ground fire coordination—also known as Close Air Support or CAS—is a dangerous and difficult business. Pilots and dismounted ground agents must ensure they hit only the intended target using just voice directions and, if they’re lucky, a common paper map. It can often take up to an hour to confer, get in position and strike—time in which targets can attack first or move out of reach. To help address these challenges, DARPA recently awarded a contract for Phase II of its Persistent Close Air Support (PCAS) program to the Raytheon Company of Waltham, Mass.
Squads of Soldiers or Marines on patrol in remote forward locations often don’t have the luxury of quickly sharing current intelligence information and imagery on their mobile devices, because they can’t access a central server. Troops frequently have to wait until they’re back at camp to download the latest updates. In the meantime, mission opportunities may erode because the information needed at the tactical edge isn’t immediately available.
Reliable wireless communications today requires careful allocation of specific portions of the electromagnetic spectrum to individual radio networks. While pre-allocating spectrum is effective in benign environments, radios remain vulnerable to inadvertent interference from other emitters and intentional jamming by adversaries.