Tactical Data Link is the means to disseminate processed information from Radars, EW, IFF, Sonars and information related to various combat function between the far-fighting Units on a battlefield.
Despite the existing Communications Compatibility and Security Agreement (COMCASA) framework for the interchange of encrypted communication between India and the US, effective joint operations using ships, submarines and aircraft shall be possible only when interoperability is achieved at the tactical level through the Tactical Data Link (TDL) of each Force.
This is one of the many issues that will be discussed at the forthcoming 2+2 Indo-Us Ministerial Dialogue in Washington DC next week when defence minister Rajnath Singh and External Affairs Minister S Jaishankar will meet their counterparts Secretary of State Mike Pompeo and Secretary of Defence Mark T Esper.
The COMCASA allows greater access to critical communication networks for interoperability and this agreement will support installation and exploitation of high-end security gadgets on the US-supplied defence equipment.
What is Tactical Data Link?
Tactical Data Link is the means to disseminate processed information from Radars, EW, IFF, Sonars and information related to various combat function between the far-fighting Units on a battlefield. TDL exchanges digital information on a near-Real-Time basis over a common network, with this tactical data updated continuously and automatically by each of the Net Units (or Node). “The TDLs have several components like the Radio set, RF generator for waveforms and blends the ‘intelligence’ which is being moved across the combat echelons in a Network-centric format. Each component of the Tactical Data Link is specified by unique hardware and software characteristics (e.g., waveform, modulation, data rates, transmission media etc.) as well as by Message and Protocol Standards,” explains Milind Kulshreshtha, C4I expert.
Link-16/Link-11 systems have been the main Tactical Data Link used by the US and its NATO allies for decades. Link 16 equipment is located on ground units, sea-based assets and airborne platforms and is continuously being enhanced for effectively produce Common Operating Picture for efficient and effective use of war-fighting assets. On the other hand, India too has its own equivalent indigenous Data Link and is being utilised onboard warships for tactical information exchange between various assets on the sea.
Explaining the technology behind this, Kulshreshtha, says “Each of the TDLs uses a different Standard Communication protocol and this Military Standard (MIL-STD) set the message standards for data-link interoperability. Therefore, combined operations between the US and Indian Forces may be possible after linking up of the two TDLs, viz. Link-16 and India’s indigenous Link equipment, which in itself is a big challenge unless an innovative methodology (like limited Message re-transmission amongst these two TDL etc.) evolved, keeping in mind Real-Time data.”
“For this, multiple interactions between two sides shall be required to finalise an Interface Protocol first, defining minimum information flow between the two TDLs,” says a top navy officer.
Recently, the Defence Acquisition Council (DAC) headed by defence minister Rajnath Singh approved induction of Software Defined Radio (SDR) technology for Tactical Communication needs of the Armed Forces. This SDR has been indigenously designed/developed through joint efforts of WESEE and Defence PSU Bharat Electronics Ltd., and a similar effort is in progress by Indian Air Force and Indian Army to accomplish their own SDR to meet own unique requirements.
Overall, the imbibing of SDR technology within India’s indigenous Data Link equipment shall be the key factor for achieving inter-operability with US Link-16 and, in turn, achieving the desired standard for combined operations between US and Indian Forces.