As a strong advocate of emerging small cell neutral hosting, we at Small Cell Forum are delighted to see the release of the Joint Operator Technical Specifications for Neutral Host In-Building – JOTS NHIB.

Before we get too technical, it’s important to see the significance of this move against a backdrop of building global momentum around neutral hosting with small cells.  It reveals that MNOs recognize the potential to scale up indoor deployments by enabling a shared multi-operator approach.

It is also a proactive step in describing exactly how MNOs would like to connect into hosted networks.  And rightly, the focus of the specifications is in the security architecture, although the five annexes cover a broad range of requirements including architecture, radio, test, operations and fulfilment.

Here at SCF, our neutral host group has been following the specification work closely since we heard about them at Small Cells World Summit in May 2019, and have been looking at advanced drafts and attending demonstration days.  Even though this is a UK MNO initiative, it has provided a useful strawman for neutral hosts having similar conversations in Europe, the US and beyond.

Neutral hosts welcome this MNO consensus on requirements because, from their perspective, it greatly reduces the technology permutations.  Not only does network sharing itself reduce cost, but alignment around the approach to sharing reduces complexity too. These together improve both affordability and scalability, which means more UK businesses will benefit and the UK mobile networks will have better indoor coverage. Furthermore, offloading the inefficiently-served indoor users also improves outdoor network capacity.

Refreshingly, the specifications are not overly prescriptive on the RAN architecture – currently an area of much disruption thanks to the rise of Open RAN. NHIB specs illustrate an S1 demarcation between dedicated MNO EPC cores and the hosted RAN.  This leaves the door open for neutral hosts to pick their own RAN architectures and vendors, optimized to the needs of indoor shared networks.  And yes, it is based on LTE – presumably because this is about providing indoor coverage for all users on all networks, so needs to work with today’s devices. That said, the general framework seems easily applicable to 5GNR and NSA and possibly even non 3GPP RATs.  And being RAN agnostic, it is also spectrum agnostic – enabling MNO-NH partnerships to tap into a broader set of spectrum opportunities including shared spectrum.

Not everyone is convinced – and it’s important to view NHIB in context of other established and emerging neutral hosting approaches. SCF has gathered a global set of neutral host’s perspectives on JOTS NHIB in new paper SCF250 Neutral Hosts’ Perspective JOTS NHIB, which can be downloaded here.

Some have commented that JOTS NHIB does not go far enough in detailing the role of neutral hosts – perhaps because JOTS represents only the MNO perspective of the partnership.  To address this, SCF is capturing consensus from the neutral hosts in a new work item. Part 1 focuses on hosting architectures, and includes JOTS NHIB, but also CBRS, hosted private networks, NH relays and hosted spectrum, virtualization, hosted Open RAN, towerco and others.  We wish to grow the neutral hosting market overall by aligning on commonalities across all approaches, whilst allowing for innovation between competing providers.