CDMA and 3G: What’s the Difference?

by MEI Vending Marketing Manager
MEI Vending Marketing Manager
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on December 06, 2013 in Cashless | 0 Comments

It’s no secret that there are a lot of acronyms in the Vending industry: MDB, VMC,  API, DEX, VDI, VMS.  Add cashless solutions into the mix and we’ve got ourselves a real acronym alphabet soup: LAN, WAN, APN, CDMA, GSM, SIM, IP...!!! 

MEI and our products are also guilty of said acronyms but that’s better left to another blog (VNR, HVB, A5K, EBDS)

Cashless technology, given its relative newness to the industry, generates a lot of questions around acronym meaning and clarifying what the actual technology does.  
A few popular questions we receive are: What’s CDMA? What’s 3G? Which of these should I consider using to connect my cashless device?

For starters:

CDMA: (Code Division Multiple Access) is a Verizon based communication solution and uses 2G/3G/4G/LTE [long term evolution] by EVDO (Evolution Data Optimized) Encryption Technology on both CDMA and all available Service Towers.


GSM: (Global System for Mobile Communication)
is an AT&T based communication solution and uses 3G by GPRS (General Packet Radio Service) Encryption Technology on 3G Service Towers only.

Note: 2G towers are still in service around North America but are being phased out to make room for newer, faster towers and communication bandwidths.

*MEI’s first telemeter, the RDP, was a 2G only device.

**MEI’s current telemeter, the Advance 5000 or A5K supports 2G, 3G, CDMA. Its modular, removable components make it future proofed for what’s next in M2M (machine to machine) communication.

     EASITRAX Advance 5000

So how do you decide if CDMA or GSM (3G) is right for you?


  • Perhaps obvious, but If you are in a region of the country where Verizon is the predominant carrier and AT&T isn’t, you want to use CDMA and vice versa. You can check this through signal testers or by talking to an MEI Technical Support Associate.
  • Does speed matter? CDMA has faster date rate speeds than 3G. Realistic speeds average around 600Kbps-1,400Kbps verses AT&T Speeds of 67.5kbps to 384kbps. Faster speeds tend to matter because often the slower the speed, the higher the probability the call will drop out or timeout to the server response.  
  • CDMA data encryption uses a different technology than 3G.  It transfers data in a single packet with an encryption key which allows the server to receive and unpack the data faster. This is a benefit because it statistically makes the encryption more stable and less likely for misinterpretation. 
  • CDMA uses a more powerful radio transmitter, which gives operators more locations to place machines, such as on the ground floor of buildings where they are below ground level and often away from a strong signal.
    When CDMA is not available the radio automatically connects to 2G.
  • Specific to the MEI Advance 5000 telemeter, 3G requires a SIM card, which can be beneficial for other applications beyond cashless.  CDMA information is instead written to internal memory on the WAN Radio card therefore does not require the purchase of a SIM card, requiring less and cost and a step in activation.  
  • What options does your preferred partner supplier provide you in the way of available radios for their telemeter? Are 2G, 3G, CDMA offered?
  • Evaluating cost.  Given the many advantages of CDMA, rates for it are often higher so evaluating these advantages against costs for your business is advisable.

In closing, I’ll add another acronym for CDMA is LTE.  J

More questions?  Ask us by commenting below or emailing us @