What is GSM?

The wireless industry has its fair share of acronyms: SMS, IMEI, LOL… and one you might not be as familiar with: GSM. Having been around since the early ‘90s, GSM is an important piece of our communications history. So what is GSM, exactly? In this article, we’ll cover what GSM means, what it does, how it does it and why it matters. 

What does GSM mean?

GSM stands for Global System for Mobile Communications, which is exactly what it sounds like: a system of protocols developed for 2G (AKA second generation) cell networks responsible for voice calls, SMS (text messages), and mobile data services. GSM is essentially the vast, overarching network that enables mobile phones to communicate with each other. 

GSM vs. CDMA

Another acronym you may have heard in relation to GSM is CDMA. CDMA stands for Code-division multiple access, and for a period of time, it was GSM’s biggest competitor in terms of communication network standards. There are a few key differences between the two:

Technology:
GSM uses a “time-division system,” which means each person is assigned a specific time slot to communicate over the same radio frequency, while CDMA uses “code-division multiplexing,” where each call is instead assigned a unique code. This allows multiple users to communicate over the same radio frequency at the same time.

SIM Card:
GSM phones rely on SIM cards to store user data, making it easy to switch phones by moving the SIM card from one phone to another. CDMA does not use SIM cards, but instead has the user’s data stored on the phone itself, making it much harder to switch from one device to another.

Global Compatibility:
GSM is the global standard, used in most countries worldwide, making travel and roaming compatibility exceptionally simple. Nowadays, CDMA is used primarily in North America (and a few other regions), making international compatibility quite limited.

What are the benefits of GSM?

GSM is the industry standard for mobile communications around the world, accounting for over 90% of market share and implemented in hundreds of countries & territories, and for good reason. So, what key features about GSM give it the edge?  

Global Compatibility

GSM being used in over 200 countries, thus being the most widely adopted mobile network standard, ensures users can roam internationally with minimal difficulty.

SIM Card Flexibility

GSM uses SIM cards, which let users move their phone numbers and wireless accounts from mobile device to mobile device with ease.

Better Call Quality

The codecs used by GSM for voice communications are efficient and enhanced to provide higher quality calls than previous technologies. 

Security

GSM networks are secured using over-the-air encryption for reliable protection.

Battery Efficiency

GSM technology is more efficient when it comes to battery usage, by design.

Data Services

GSM led us into the second generation of mobile communications with mobile internet. This enabled features like text messaging (SMS), multimedia messaging (MMS) and early mobile data services (GPRS/EDGE).

What are GSM phones?

GSM phones are wireless devices that operate on the GSM network. They use a SIM card to connect to a wireless carrier’s cellular network in order to make phone calls, send texts and access the internet. So, if your phone is GSM-compatible, you can change carriers just by swapping your SIM card. GSM phones can be used globally, making them ideal for travel. GSM phones also come in a variety of makes & models, from your basic bar phone to the flip phones to the advanced touchscreen smartphones we know today.

How does GSM work?

GSM works by connecting phones to a cellular network via a SIM card, which stores account information (like a phone number) for authentication purposes. Here’s a more simplified breakdown of how it all happens:

SIM Card

Stores user information (phone number, account details) to authenticate with the network and can be easily switched between capable GSM phones.

Radio Signals

Data, voice and text are transmitted using specific radio frequencies between the GSM phone and the cell towers.

Cell Towers

The phone, thanks to its SIM card, connects to nearby base stations (AKA cell towers) to communicate with the wireless network.

Switching & Routing

The data, calls and messages are directed to their correct destination (e.g. another GSM phone user) via network routing centers.

Security

These communications are encrypted over-the-air to ensure secure voice & text transmission.

That’s the ABCs of GSM

As you can see, GSM is essentially the backbone of wireless communications as we know it today. If it weren’t for the second-generation network protocols brought on by GSM decades ago, we wouldn’t be sending photos & videos to friends & family the way we do now. And as the global standard for mobile communication, it makes sense to have a GSM phone and a wireless carrier that runs on a GSM network—especially if you find yourself traveling outside the US. Ultra Mobile knows the importance of staying connected across the globe, which is why we provide affordable, reliable wireless service with unlimited talk & text to 90+ international destinations and great international roaming options, all on a GSM network. Click below to learn more about why Ultra Mobile is the best option for your wireless needs.