GSM vs CDMA: Which is Better?

What is GSM?

GSM stands for Global System for Mobile Communications. GSM is a cellular network technology that uses SIM cards to store user identity and number.

Because it uses a SIM card, GSM users can move their phone number to another device simply by moving the SIM card.

GSM was widely used on 2G networks and became the foundation for the development of cellular networks such as 3G, 4G LTE, and 5G.

Some operators using GSM technology in Indonesia include Telkomsel, Indosat, XL Axiata, and Tri.

What is CDMA?

CDMA stands for Code Division Multiple Access. This technology uses special codes to distinguish each user within a network.

In older CDMA systems, the phone number was typically tied directly to the device. Therefore, users could not always move their numbers as easily as on GSM networks.

CDMA was once used by several operators in Indonesia, such as Smartfren, Esia, Flexi, and StarOne. However, CDMA networks are now almost entirely unused as operators have transitioned to 4G LTE and 5G technology.

Table of Differences Between GSM and CDMA

Aspect	GSM	CDMA
Full Name	Global System for Mobile Communications	Code Division Multiple Access
How it works	Divides the network based on time and frequency	Divides the network using special codes for each user
User identity	Stored on the SIM card	Generally stored or tied directly to the device
SIM card usage	Uses a SIM card	Older CDMA generally does not use a regular SIM card
Changing devices	Easy, just move the SIM card	More difficult because the number is usually tied to the device
Network coverage	Wider and used in many countries	More limited coverage
Operator choices	More	Fewer
International roaming	Easier and widely available	More limited
Device availability	Many device choices	More limited device choices
Voice quality	Good, but depends on the network	Previously known for fairly clear voice quality
User capacity	Limited capacity based on frequency division	Can accommodate many users on the same frequency
Security	Uses encryption and SIM card authentication	Uses special codes to distinguish users
Power consumption	Depends on device and signal strength	In some conditions can be more power efficient
Internet speed	Evolved from GPRS, EDGE, 3G, 4G, to 5G	Evolved from CDMA2000, EV-DO, then switched to LTE
Current usage	Still used through 4G and 5G networks	Older CDMA technology is almost abandoned
Global popularity	Very widespread	More used in certain countries
Ease of switching operator	Relatively easy by replacing SIM card	More complicated on older CDMA systems
Flexibility	More flexible for users	More dependent on operator and device
Example operators in Indonesia	Telkomsel, XL, Indosat, Tri	Smartfren CDMA, Esia, Flexi, StarOne

Differences in How GSM and CDMA Work

The main difference between GSM and CDMA lies in how they manage users within the network.

GSM divides communication channels based on time and frequency. Simply put, each user gets a specific portion to make calls or send data.

Meanwhile, CDMA allows multiple users to share the same frequency. Each user is distinguished by a special code so that their signals do not interfere with others.

Although their working principles differ, the goal of both technologies is the same: to connect devices to the operator's network.

Differences in SIM Cards

GSM is known as a network that uses SIM cards. The card stores information such as the phone number, customer identity, and operator network data.

The advantage of using a SIM card is that users can easily switch devices. Simply remove the SIM card from the old phone and insert it into the new one.

In older CDMA, user identity was typically embedded directly into the device. Changing devices often required assistance from the operator.

Some CDMA networks later began using special cards called RUIM. However, their usage was not as widespread as SIM cards on GSM networks.

Differences in Network Coverage

GSM has broader coverage because it is used by most operators worldwide. GSM users also find it easier to get service when traveling abroad.

CDMA has more limited coverage. This technology was once widely used in countries such as the United States, South Korea, Japan, India, and Indonesia.

Due to its smaller global support, CDMA devices often face limitations when used in other countries.

Differences in Signal Quality

The signal quality of GSM and CDMA actually depends heavily on location, number of towers, building conditions, weather, and the number of users on the network.

CDMA was once known for stable voice quality and the ability to serve many users on a single frequency.

However, GSM is superior in terms of network availability. Because there are more GSM operators and towers, users generally find it easier to get a signal.

Nowadays, network quality is more influenced by 4G LTE and 5G technology than by the GSM or CDMA distinction.

Differences in Internet Speed

On GSM networks, internet development began with GPRS, EDGE, 3G, HSPA, 4G LTE, and now 5G.

Meanwhile, CDMA evolved through CDMA2000 and EV-DO technology. At its peak, EV-DO was able to provide fairly fast internet connections.

However, CDMA development did not progress as extensively as GSM. Most CDMA operators eventually shut down their old networks and switched to 4G LTE.

Advantages and Disadvantages of GSM

Advantages of GSM

• Wider network availability.
• Easy to change devices by moving the SIM card.
• More operator and data plan choices.
• Supports international roaming.
• More diverse device options.
• Easier to use when traveling abroad.

Disadvantages of GSM

• Signal quality can decrease when the network is too congested.
• On older 2G networks, voice and internet quality were limited.
• Speed heavily depends on location and operator service.
• SIM cards can be lost or damaged.

Advantages and Disadvantages of CDMA

Advantages of CDMA

• Can accommodate many users on a single frequency.
• Previously known for fairly good voice quality.
• More efficient frequency usage.
• Interference between users can be reduced through the use of special codes.

Disadvantages of CDMA

• More limited network coverage.
• Difficult to change devices on older CDMA systems.
• Fewer operator choices.
• Limited device options.
• International roaming is more difficult.
• Older CDMA technology is almost entirely unused.

Does Smartfren Still Use CDMA?

Smartfren was indeed known as one of the CDMA operators in Indonesia. However, Smartfren has discontinued its CDMA service and switched to using 4G LTE networks.

This means older CDMA devices can no longer access the Smartfren network. Users must use devices that support 4G LTE or newer technology.

Is GSM Still Used Today?

The term GSM is still often used to refer to operators that use SIM cards. However, modern cellular networks have evolved far beyond 2G GSM technology.

Today, the majority of users use 4G LTE and are beginning to transition to 5G. These technologies are used for internet access, voice calls, messaging, and various digital services.

Thus, although the term GSM remains popular, the technology used daily now is generally LTE and 5G.

GSM or CDMA: Which is Better?

If compared based on current user needs, GSM is superior because of its wide coverage, more operator choices, and ease of use.

However, the comparison between GSM and CDMA is no longer very relevant for choosing a modern cellular network. What matters more today is ensuring that the device supports:

• 4G LTE or 5G networks.
• The frequencies used by the operator.
• VoLTE technology for calls.
• Physical SIM card or eSIM.
• Operator signal coverage at the user's location.

Conclusion

GSM and CDMA are two cellular network technologies with different working principles. GSM uses a SIM card and has broader global coverage. Meanwhile, CDMA uses special codes to distinguish each user within a network.

CDMA once had advantages in capacity and voice quality. However, limitations in devices, operators, and coverage led to its gradual abandonment.

Currently, most operators have shifted to 4G LTE and 5G networks. Therefore, users do not need to focus too much on choosing between GSM or CDMA. Instead, choose an operator based on signal quality, internet speed, package price, and network coverage at your location.