The Multi-IMSI Revolution Is Coming


The Multi-IMSI revolution has the potential to completely redefine the way we see some of the world’s largest brands.

What Is an IMSI?

An International Mobile Subscriber Identity (IMSI) is a unique 15-digit number that identifies every mobile network user globally. The IMSI is divided into two parts. The first part is a six-digit or five-digit number based on North American or European standards, respectively. The initial set of numbers identifies the mobile network operator in a specific country to which the user is subscribed. The second part of the IMSI number is allocated by the network operator to uniquely identify the subscriber.

What Are the Benefits of Multi-IMSI Sims?

In short – coverage.

One of the main challenges faced by corporations seeking to ensure that all their users enjoy a similarly reliable and useable experience when they are deploying new mobile technology to enable sales and field-based teams. 

One of the challenges of this has always been choosing the right cellular/mobile network for all of your staff.  The more locations your business operates from the more challenging this can be as different networks have better coverage in specific locations. 

In the past this may have meant signing multiple agreements with multiple network providers based on the primary working locations of your users, however, this creates billing and management headaches, can often result in mixed contractual terms, fluctuation of cost and inconsistent user experiences.  In addition, having multiple providers fails to solve the problem if users travel as part of their role as coverage will continue to be variable. 

This is where multi-IMSI technology comes in, it can work on a physical sim, esim or the upcoming isim technology to allow users to autonomously switch between networks based on available bandwidth.  This functionality has been at the core of low-bandwidth IoT applications for some time as it has been necessary to ensure devices deployed to numerous, often remote locations have access to some kind of network to connect, however, this technology is now available for high-bandwidth enterprise applications as costs have decreased, technology has improved and network availability has increased.

Multi-IMSI v’s Similar Older Technologies

Some readers of this article may point out, however, that there have been multi-network sim cards in the past.  These generally came in two forms:

  1. Guided multi-network sims – These sims would prioritize a home network and only roam onto alternate networks where the home network had no signal.  The usefulness of these was limited however as the home network priority often led to poor bandwidth and usage of the functionality was restricted to one country.
  2. Single IMSI multi-network sim cards – These sims are essentially foreign sims from a network provider that has multiple roaming agreements with the country that the sim was being used in.  The vast majority of the time these roaming agreements are restricted to around ½ of the available networks.  For instance if you take a Vodafone UK sim card to the USA you can only roam on T-Mobile & AT&T. With a multi IMSI sim card your options can then open up to also allow the use of the Verizon and Sprint networks.

Esim’s Are Just a Small Part of a Much Larger Solution

Much of the current hype around esim use cases has centred around things like the ability to add a local sim to your device when you travel to arrive in a new country, therefore, mitigating roaming fees but most major network operators have bundled provisions in place for well-travelled countries that negate much of the cost benefits of doing this in most cases except for the most extended of stays in foreign locations. 

Even with the simplicity of adding an esim to a device most users baulk at the sorting between primary and secondary use cases for the dual sims now on their device, if travelling within Europe or South America they may often be moving between countries on a daily basis and if that wasn’t enough, the reality is that currently they are still making and receiving voice calls on their original sim card, incurring the very same roaming fee they would have done if they had just used the data of their original sim card.

The Death of the Standard Voice Call 

If I glance down at my recent calls list on my phone it looks very different than just three years ago.  95% of my calls are now made from either Microsoft Teams, Whatsapp or Facetime, of the other 5% nearly all are spam callers whose calls I didn’t answer and perhaps 1% are a local business such as my dentist.

The reality is that my phone number, one that 15 years ago I paid a premium for to ensure it was highly memorable is now the least used identifier by which I am contacted.  If I was to suddenly not have access to my phone number, my biggest inconvenience wouldn’t be that people aren’t able to contact me, it would be the thousands of applications that use SMS as a means of 2-factor authentication.  If I instead used email authentication or, even better an application like Google Authenticator or one of its peers then I would pretty much have no need for a phone number.

If I don’t need a phone number, why would I restrict myself to the coverage of a single carrier? And this brings me to the main point. In a world where phone numbers aren’t necessary, my buying criteria can adjust to ensure I have access to the widest range of operators at the most cost-effective price.  I no longer care about the history or perceptions that my carrier has created with clever branding and marketing, all I care about is ensuring I have the largest number of signal bars available on my handset at any given location, I want access to as many networks as possible, with a solution that remains cost-effective.  I want a multi-imsi sim card.

How Will This Change the Major Player in Telecommunications?

But what about the existing networks? Won’t someone please think of the networks?

Traditionally, the share price of carriers around the world has been heavily correlated with the number of subscribers they have, this has meant huge marketing spending, sponsorship of often dubious and conflicting network “Awards”, and conflicting and often misleading claims surrounding coverage and speed. 

A truly multi-IMSI world could look very different, it would be a world where networks were forced to compete based on the actual detected speed and availability of their infrastructure, where they no longer spend huge amounts of cash sponsoring football teams or F1 teams and instead invest exclusively in the expanding and improving their infrastructure essentially “marketing” themselves through the actual quality of the product they provide rather than outdated perceptions.

It’s a world where smaller entrants could enter local markets to disrupt an industry with currently insanely high barriers to entry to drive increased value for customers, where local communities could band together to resolve local connectivity issues and even earn additional revenue from visitors/tourists utilizing their infrastructure. 

These are just some of the possibilities with this rapidly evolving technology, multi-IMSI is constantly morphing with improved technology, pricing, and innovative disruptors quickly moving the market, the next 5 years have the potential to see a sea change in how mobile telecommunications around the world operates and it will be incredibly exciting to witness.

Owen Keenan-Lindsey, CEO of Assimilated International, providing complete ICT solutions to large SME & enterprise businesses throughout the UK & USA.

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