TRAI's 5G Slicing Rules Should Test User Harm, Not PRB Use

TRAI's Proposed Guardrails for 5G Network Slicing

The Telecom Regulatory Authority of India is building guardrails for 5G network slicing, the technique that lets a single physical mobile network be divided into logically separate slices for different service needs. Those slices can be optimised for high-speed mobile broadband, massive sensor connectivity or ultra-reliable low-latency uses such as industrial automation.

TRAI's central proposal is to monitor how heavily each cell's radio resources are used through Physical Resource Block, or PRB, utilisation. The plan targets the Cell Busy Data Hour and would set a benchmark under which no more than 1 per cent of cells show daily PRB utilisation above 80 per cent. If a cell runs above that threshold on five days in a month, the operator would have to add capacity; if utilisation remains above 80 per cent after a month, the cell would have to be removed from slicing arrangements.

The editorial in The Hindu Business Line says the goal is understandable: premium slices should not be created by forcing ordinary users into congestion. But it argues that PRB utilisation measures how much radio resource is consumed, not who is using it or how the resource is allocated. Therefore, the proposal should be recast as an outcome-based test that examines whether ordinary internet access actually suffers because of premium network slices.

That conclusion draws on the approaches of several international regulators. BEREC in Europe, Ofcom in the UK, ARCEP in France and the US Federal Communications Commission have accepted or proposed monitoring differentiated services, as long as they do not undermine open internet protections or enable paid prioritisation.

Why the 80% PRB Rule Is a Weak Fairness Test

Why TRAI's 80% PRB Threshold Is a Blunt Instrument

The editorial's core criticism is that a percentage utilisation benchmark cannot establish fairness by itself. A cell at 75% PRB utilisation could still give a premium slice disproportionate resource access, while a cell crossing 80% does not prove ordinary subscribers experienced material quality degradation. In other words, 80% is a reasonable congestion warning light, but it is not a stand-alone test of net neutrality.

This matters because the remedy TRAI proposes is intrusive: after five days of above-80% utilisation, operators must add capacity; if the problem persists for a month, the cell must be dropped from slicing. A purely volume-based rule could force costly network investment or forfeit slicing revenue even when no baseline user has been harmed.

What BEREC, Ofcom, ARCEP and the FCC Have Accepted

International regulators have already moved toward differentiated services with conditions. BEREC, Ofcom and ARCEP accept them provided they do not undermine open internet access. The FCC proposes monitoring slicing to ensure it is not used to sidestep rules against paid prioritisation, throttling or unreasonable discrimination. That consensus supports the editorial's view that the right question is impact on ordinary traffic, not raw resource usage.

The Commercial Opening for Indian Operators

If TRAI adopts an outcome-based approach, Indian operators would be able to monetise genuine spare 5G capacity. The condition is that premium services must demonstrably not squeeze baseline users. For operators, that means the commercial prize is linked to producing evidence of spare capacity and baseline quality, not simply staying under an arbitrary utilisation number.

What Operators, Regulators and Enterprise Buyers Should Watch

• Operators: Build trial data showing ordinary subscribers' latency, throughput and drop rates before, during and after premium-slice activation, not just PRB percentages, because TRAI's five-day and one-month triggers are numeric congestion rules and the editorial challenges their fairness logic.
• Enterprise buyers of 5G slices: Ask operators how they will prove that premium slices do not degrade baseline traffic. A cell operating at 75% PRB utilisation can still allocate resources unequally, so written service-level commitments for ordinary access may matter more than headline slice performance.
• TRAI and other regulators: Compare the Indian thresholds with BEREC, Ofcom and ARCEP's outcome-based conditions and the FCC's safeguards against paid prioritisation before finalising rules.
• Operators with genuine spare capacity: Start documenting spare capacity that can be monetised through slicing while demonstrating no material harm to regular users, since that is the route the editorial says should remain open.