New white paper from TCCA’s Broadband Industry Group looks at the status and challenges of implementing priority mechanisms for first responders
With more and more countries considering implementing broadband public safety services over existing commercial mobile networks, the spotlight is on ensuring that first responders do not struggle to access the network when there is high demand from consumer users.
There are several benefits in public safety using commercial networks, including fast time to market, access to spectrum, and reduced cost of ownership through network sharing. However, first responders have the most stringent requirements for network availability and service quality. During a major unplanned event such as a terrorist attack or natural disaster, commercial networks can become congested, thereby potentially preventing public safety users gaining critical access.
To avoid this, different prioritisation mechanisms need to be implemented to ensure that first responders get the highest level of priority to the shared Radio Access Network (RAN) when they are using a commercial network infrastructure.
There are already many prioritisation mechanisms that have been standardised by 3GPP to provide mission critical services. These include Access Class Barring (used in many countries as a “defence” mechanism against overload that could lead to a total outage), Pre-emption, Admission control through Allocation and Retention Priority, and Quality of Service Class Identifiers. In addition, implementing national roaming between commercial networks is also a consideration as a cost-effective way of gaining enhanced network resilience.
The new white paper ‘Public safety prioritisation on commercial networks’ reviews these prioritisation mechanisms and the legal considerations required to implement them.
The US and the UK are rolling out public safety services over commercial networks and have successfully tested prioritisation and pre-emption features. In terms of the technology, prioritisation of first responders connected to a shared commercial RAN is no longer a challenge. However, there are legal issues that need to be addressed country by country to allow pre-emption and national roaming.
As an example, in many countries national roaming is not allowed as it could harm competition between the different mobile operators. Some countries like Belgium and Finland have already taken legal action to enable national roaming between all their mobile operators, limited to critical communications users. Norway has national roaming capability for qualified users with a role or function of vital interest to the society. In Austria, Access Class Barring is forbidden as commercial users cannot be discriminated from public safety users.
Depending on the local legislation, resource pre-emption on the commercial network can be a legal issue, and first responders having first priority on the mobile network might be in contradiction with net neutrality.
The white paper includes inputs from governments and critical communication network operators, and looks forward to prioritisation in 5G, including network slicing and Non-terrestrial networks (NTN).