SIM Card Basics for Digi Cellular Devices

This Knowledge Base Article is intended to provide information to better prepare Users for a successful cellular device implementation. All 4G/LTE devices require a SIM card for network connectivity, and it is not always clear what options or requirements are present.



A Subscriber Identity Module, or SIM, is a small plastic and metal chip used to authenticate a device for cellular network connectivity. It is issued by the network provider and is unique to a line of service on account. Without a SIM, today’s 4G/LTE devices will not be allowed access to cellular data networks.



There are several SIM form factors available today, so Users should take note of the options before purchasing service. All of Digi’s routers and gateways use a Mini-SIM, or 2FF, while our XBee Cellular Modules use Nano-SIM, or 4FF. For future versions and new products, Users should always consult our data sheets or product guides for information regarding SIM form factor requirements.


More information on SIM Formats with scaled images can be found here:



APNs are used by the network to indicate what kind of network connection should be established with the device. This can include IP address assignment (public/private, static/dynamic) or if other security protocols should be enforced. These are provided by the network provider and should always be used when configuring the device.                                                                             

Examples:  vzwinternet, 10569.mcs, or


User Names and Passwords are not typically required and should only be used if the service provider indicates they are.


For assistance with programming APNs, User Names, or Passwords on your Digi device, please consult the User’s Guides located on our Support Site,



There are many ways of obtaining network access for your Digi cellular devices, including from Digi directly. We offer easy-to-use, competitive services for data networks in North America as well as for International deployments.


For assistance or to obtain a quote, please contact us:

By Phone     1-877-912-3444 option 2, then option 3, then option 7

By Email



To ensure you have everything you need, please consider the following Checklist:

·         Cellular Device: Digi Gateway, Router, or XBee Cellular Module

·         Cellular Line of Service: for data only, M2M or IoT devices

·         SIM Card: 2FF for Routers and Gateways, 4FF for XBee Cellular Modules

·         APN and Username/ Password (if applicable)

·         User’s Guide and relevant documentation from

·         Point of Contact for Support


Thanks again for your continued support; if we can assist in any way, please contact us. 

Last updated: May 10, 2018

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