Network Advisor

Too many confusing network acronyms? We'll try to demystify the alphabet soup of network standards and identify what is important to getting great performance and clarity. For the most part, we'll ignore standards not in use in the USA to make life a lot simpler.

1G to 5G (Generation)

Over the years technological improvements have been bundled into five categories, from 1G to 5G. These are not actual standards, but a way to group the different generations of networks used. Let's take a quick review of the Gs!

First Generation 1G

The first mobile phones were an analog system and is now labeled a 1G service. These networks were mostly discontinued by 2008 as they use more bandwidth than the newer digital networks, were highly susceptible to interference, and offered no security. Anyone with a scanner could easily listen in on these calls. In addition, the phone identification codes could easily be cloned to allow making calls without paying.

Second Generation 2G

As the costs for digital technology plummeted and new frequency bands became available, networks switched over to digital designs. These greatly expanded numbers of calls that could be handled in a given area. The call data is encrypted to make it very hard to intercept the call unlike the 1G systems, and the design also helps eliminate fraud. Digital also eliminated static and most interference problems. 2G systems provide a means to send low-speed digital data, such as text messages and signaling.

The 2G systems are available in different network types including GSM, CDMA and iDEN. GSM is considered a world standard and is available in most countries by at least one carrier. Japan and South Korea use different incompatible systems, so few phones outside these countries will work there. The next section Voice Networks explains this in more detail.

The downside to the digital networks is voice quality suffers due to the lossy compression techniques used, dropouts occur when the signal strength gets too low (whereas analog degrades slowly), and more towers may be required to get adequate coverage in rural areas if the higher-frequency bands are used.

As networks evolved, several technologies were added to boost the data speeds. While some marketing promotes these as 3G systems, they are really considered in-between generations. GPRS was created for GSM networks and is considered a 2.5G system. CDMA systems got an enhancement called 1xRTT which is also considered a 2.5G service.

GPRS networks further evolved to the EDGE standards, which can triple the speeds of the GPRS standards. It's a bit of an overlap to the lowest performing 3G systems but is commonly referred to as a 2.75G service.

2G is discontinued in the USA.

Third Generation 3G

Third generation systems are defined as offering technologies that can transfer data at a peak rate of 200 kbps or more. 3G security was further improved over older 2G systems with better encryption and protocols.

Some of the network names you'll see associated with 3G services are EDGE Evolution, EV-DO, and HSPA. We'll explain these a bit more in the Data Standards section below.

3G is discontinued in the USA.

Fourth Generation 4G

To have a true 4G system, the device and network should have a peak download data rate of 1 Gbps or better while stationary, and 100 Mbps when moving in a vehicle such as a train or car.

Currently, many phone companies are touting their new high-speed 4G networks. While these are faster than their initial 3G services, it doesn't meet the initial 4G requirements, which are 500 times greater than the 3G minimum. At the end of 2010, it was decided that if a technology has the future potential to meet the 4G standards, it can be called 4G. For example, LTE Advanced is considered 4G even though the LTE systems do not come close to the 4G minimums, yet they are far faster than the older 3G standards.

Fifth Generation 5G

5G systems are replacing much of the 4G systems, but often using much higher frequencies. 5G signals can be blocked by obstructions such as buildings. Today (2023) both 4G and 5G are used together to get the best coverage. 5G offers even faster speeds and lower latency over older systems.

 

Voice Networks

Perhaps a little confusing, but all voice networks today are really low-speed data networks! The audio is converted to a digital data stream and back. A limited amount of slow data is supported to handle dialing, connections and other secondary functions.

There are three voice networks in use today throughout the USA. Each carrier typically offers one voice network, although Sprint-Nextel used to offer two networks. Most phones are sold to operate on a single specific carrier, but often the phone can actually communicate with other networks. This may be done for roaming, or to make the phone usable in other countries.

While there are number of good reasons to pick one technology/carrier over another, you need to ensure you have good reception in the locations you plan to use the device. Often there are dead-zones or smaller cities without coverage. Some carriers offer a 30-day full refund test period to validate it works where you need it. Check with the carrier if they offer this program and what the details are.

GSM - Global System for Mobile communications

The GSM standard is estimated to have about 80% of the world's market, and about 50% of the USA market. In the USA, both AT&T and T-Mobile have GSM networks. GSM networks typically use one of four frequency bands: 850, 900, 1800 or 1900 MHz. The bands selected depend on which frequencies the carrier supports and the country that made the specific bands available. For example, AT&T only uses the 850 and 1900 bands, which varies depending on the specific service area. T-Mobile uses the 1900 MHz band nationwide, and 850 MHz in South Carolina (due to an acquisition).

A Quad-band phone indicates it supports all four standard GSM frequency bands. A Quad-band phone will work in almost every country except Japan and South Korea, where no GSM service providers area available to roam to. Most phones sold today support many bands.

 

CDMA - Code Division Multiple Access

CDMA is an alternative standard to GSM. About 50% of the USA market uses CDMA. Other than the two large GSM providers, all the others use CDMA. This includes Alltel, Cellular South, MetroPCS, US Cellular and Verizon. In the US, three frequency bands are used 800, 1900 and 2100 depending on the carrier and location.

Generally, CDMA phones are not usable in other countries but msot newer models include GSM support and are sometimes marketed as a 'world phone'.

 

iDEN - Integrated Digital Enhanced Network

This is a rather old communications technology. In addition to normal direct connect phone calls, it offers a "push-to-talk" option to connect two iDEN users. Sprint-Nextel has the only iDEN network in the US, although it also sells network access to Boost Mobile. Sprint-Nextel started phasing the service out beginning in 2013. Sprint-Nextel uses the 800 and 900 MHz bands for this service, although the Walkie-Talkie service is only on the 800 MHz band. Sprint was aquired by T-Moible in 2020, and iDen has been abandoned.

 

Data Standards

Networks today support a range of data standards, in the quest to provide faster and faster service. Often these standards use entirely different technology and frequencies from the voice network. When a high-speed network standard is unavailable or congested, it automatically drops to one of the lower performance standards. GSM and CDMA each offer a separate set of standards for data, although the new LTE standard can be found on both networks, since it is not dependent on the voice standards. In the later section, Data Speed Guides, we compare the basic performance of each data network.

Data on GSM

GPRS

General Packet Radio Service (GPRS) is one of the oldest currently available data standards on a GSM system. It is a fairly slow service, typically slower than an old 56 kbps dial-up modem. It is sometimes called a 2.5 G service. It can deliver slow Internet access, instant messaging and a few other services. The standard can offer simultaneous voice and data, but most phones are not designed for simultaneous voice and data to save costs.

EDGE

Enhanced Data rates for GSM Evolution (EDGE), is also called Enhanced GPRS (EGPRS) offers up to 3 times the data rates of GPRS. It is considered a 2.75G type service and is considered quite slow today.

UMTS

Universal Mobile Telecommunications System (UMTS) is a completely independent data network. It also goes by the name 3GSM. This allows simultaneous voice and data, since the two do not share the same paths. It's also considered a true 3G network as its speed is far better than GPRS or EDGE standards. The downside is UMTS consumes more power, either requiring a larger battery or acceptance of shorter connect times.

UMTS is available on a number of bands from 850 to 2100. Some phones are offered with multi-band UMTS support to provide operation in different countries. These frequencies are different than those used for voice/GPRS/EDGE.

Evolved EDGE

Evolved EDGE, also called EDGE Evolution, further boosts the data performance of EDGE with speeds up to 1 Mbps. It also reduces the latency, so streaming videos became practical. This is considered a 3G service.

HSDPA and HSUPA

High-Speed Downlink Packet Access (HSDPA) and High-Speed Upload Packet Access (HSUPA) is an enhancement of UMTS service to further boost data performance. Its considered a 3.5G service. It's speeds allow for real-time video and mobile TV over the network.

HSPA+

Evolved High-Speed Packet Access is another major enhancement to UMTS, further boosting the data rates up to a theoretical 84 Mbps for devices that support it. It is often called by the carriers as a 4G service.

Data on CDMA

1xRTT

One times Radio Transmission Technology (1xRTT), is also called CDMA2000 1x, offers basic data while a call is in progress. It is a 2G service.

1xEV-DO Rev. 0

Evolution-Data Optimized (EV-DO) offers a data only service with improved performance, but only while there is no concurrent voice call. This version has been replaced with Revision A in the US. EV-DO versions are considered 3G services.

1xEV-DO Rev. A

Revision A boosts the upload rate dramatically, and also gives a small boost to the download rate. For US networks that support EV-DO, this is the current revision in use. Like EV-DO Rev 0, this is a data only service, and cannot be used while a voice call is in use.

1xEV-DO Rev. B

Revision B significantly boosts both the download and upload rates again from revision A. There are no networks in the US that use Rev B, and no commitments to do so. It is likely LTE will be implemented by carriers instead of Rev B.

Data on GSM and CDMA

LTE

Long Term Evolution (LTE) offers very high data rates along with low latency. It complements either GSM or CDMA networks, since it is a separate system from the voice component and older data services. It's considered a 3.9G service but is generally promoted as 4G. LTE networks are being put in place by AT&T, MetroPCS and Verizon for major cities.

LTE Advanced

Long Term Evolution (LTE) pushes the data speeds up to 1 Gbps for downloads.

LTE Advanced Pro

Long Term Evolution (LTE) further pushes the data speeds up to 3 Gbps for downloads. It is truly a 4G service.

Data Speed Guides

These show the peak possible download and upload speeds for each technology, commonly used today in the United States. Within each chart, they are organized from the oldest poorest performing standard to the latest best performing standard.

The carrier may not support every technology shown and/or the highest speed option in every area. As the device moves further from a cell tower, the data connection may also have reduced speeds. With network congestion the connection may drop down to a lower performing network service as well.

A device that supports a specific technology may not support its maximum speed either. A poor rule of thumb is to expect 30% or less of the peak rate stated for real world environments.

GSM

CDMA