This post is also available in: עברית (Hebrew)
By Dov Lachman
A new Israeli emergency messaging system began operations on Friday, July 25, covering almost the entire country. The system, known as “Meser Ishi” (Hebrew for “personal message”), sends text messages to almost every Israeli cellphone user – but so far only to subscribers of Israel’s three main cellular service providers: Cellcom, Pelephone and Partner. These new messages, similar to normal SMS text messages, are sent when rocket and missile launches are detected, urging recipients to find shelter.
The Home Front Command emergency messages are broadcast on a unique channel called CB (Cell Broadcast), an inherent part of the ongoing communications process in every active cellular device – active even during calls, web surfing or use of various apps.
The CB channel is defined by the international communications regulation body, dictating its structure, application and use by end users to the cellular manufacturers (manufacturers of end point devices and vendors of cellular network core components).
The CB signal broadcast originates from a single cellular site or a group of sites (at the discretion of the cellular provider), sent to every device getting service from that site while the message is broadcast. Unlike the standard method of operation used in cellular networks – a process called paging, in which the network searches for a specific device for calls, SMS messages or web surfing – the CB process calls for the cellular site to broadcast to all phones connected to it at that moment, without any knowledge of their identity. It’s a one-way process, and the cellular network has no way of knowing if the subscriber received the CB message or not (unlike an SMS or a call, where the phone reports any failures or disturbances back to the network).
The IDF’s Home Front Command divided the country into specific emergency regions, and the cellular providers, in turn, feed the CB messages only through sites providing cellular coverage for that specific region.
The original goal was to use the broadcasting channel to enable location-based services (LBS), such as advertising, weather, municipal messages and more. The main advantage of this system is its speed, the immediacy in which messages are receiving by phones, without relying on complex protocols or internet surfing conditions.
The low levels of demand for CB services, and location-based services in general, led to both end device manufacturers and infrastructure vendors to neglect the technology, causing many compatibility issues between manufacturers and cellular service providers, in Israel and abroad.
The “Meser Ishi” technology development process began in 2008 (!). Adapting the technology for local cellular networks, a project led by the IDF’s Home Front Command, began in 2010 with a huge, 30-million-shekel budget. Israel’s three main cellular providers, after initially resisting the changes, eventually complied with the regulations laid out by Israel’s Ministry of Communication. Most of the subscribers who own Android-based smart phones, in addition to owners of older devices, will receive the Home Front Command messages.
Aside from the many advantages of receiving alerts on cellular phones, there are a few technological and practical disadvantages:
- “Leakage”: Sometimes, usually due to a cellular network’s management of its radio resources, subscribers will receive alerts even if they are outside the alerted region
- Configuration: Some devices have various options that have to be configured by the user before enabling the service (language, channels, etc.)
- Regulation (1): There have been ongoing discussions regarding regulation for five years now, including Ministry of Communication cellular device import licenses requiring CB support.
- Regulation (2): The Ministry of Communication succeeded in forcing only the three main providers to cooperate with the Home Front Command. The licenses given to other providers by the state do require them to support CB messages, but that requirement is not enforced enough.
Subscribers of smaller cellular providers (Golan Telecom, HOT Mobile), whose service is not based on the infrastructure of the three main providers, will not be able to receive the Home Front Command CB messages. Subscribers of virtual providers (MVNO), such as Rami Levi and Alon Cellular, will receive the CB messages, subject to the same limitations as subscribers of the main providers (types of devices, coverage areas, etc.).