What is the Difference Between Dual SIM and Dual Modem Solutions?

If you’re in the market for a cellular solution for your primary or backup/ failover uses, you might find the number of options overwhelming. There are several factors that go into selecting the appropriate router for any application. One important thing to consider is whether you need a solution with dual SIM card slots or dual modems. Read on to find out more about the differences and how to determine which solution is right for you. 

Dual SIM Modems

This is a single modem that accommodates two total SIM card slots. Since there is only one modem, only one SIM card can be connected to at a time. When two SIM cards are present, and the first SIM card fails to connect, the secondary SIM will take over. Once the first SIM can reconnect, it switches the connection back to this first SIM. Note that the router cannot detect poor performance and failover based on that. If the SIM can connect, it will stay connected until its network connection fails. 

Users with metered data plans may insert SIM cards from the same carrier. Once the first SIM reaches its data limit, a configuration rule tells the router to switch to the secondary SIM card. This rule also tells the router when the data plan has been renewed for the month and switches back to the primary SIM. 

Not only will the modem auto switch between SIM cards, but users have the option to manually switch between the SIM card connections. This is especially helpful in cases where users travel. Having the ability to switch between different carriers allows the user to determine which connection is best for their usage. 

Keep in mind that with only one modem, there is some time lag between the SIMs switching. This process can take a few minutes to complete. If your application cannot afford any downtime, this solution is not the best.

Dual Modem Routers

As it sounds, dual modem routers have two modems, which may each have dual SIM card slots as well. Each modem can be connected at the same time, while also supporting failover to their secondary SIM card slots. This solution has little to no downtime because the modems are already connected to their networks. 

Load balancing is possible with dual modems and along with QoS (Quality of Service) rules you can provide more bandwidth to your most important devices and applications. Alternatively, you may take advantage of SD-WAN functionality. For example, using Peplink’s SpeedFusion technology. Like load balancing, all connections are active simultaneously. The difference is that all connections are combined into one and therefore provide more throughput for your devices. 

So, if you’re looking for nearly 100% uptime, using a dual modem router as a backup for your primary wired Internet connection can give you that. It can also provide you increased bandwidth for those important connections on your network. 

Interested in learning more about which solution is best for your specific needs? Contact our team Monday through Friday, 9am to 6pm CST by phone, email, or chat!