No, you cannot manually assign a global IP address to your Air SIM. However, depending on your intended usage, Soracom provides alternative options that may provide the functionality you require.
I want to identify my Air SIM devices by their IP address
In certain environments, you may want the ability to identify your Air SIM devices based on their IP address, such as to configure a firewall to allow specific connections, or to route incoming connections to your server.
While you cannot assign IP addresses to each Air SIM device, you can create a VPG (Virtual Private Gateway) in your account and enable the Fixed Global IP address option. When enabled, your VPG will be assigned two global IP addresses. You can then add your Air SIM devices to a group, and attach the group to the VPG. Once attached, the source IP of each Air SIM device will appear as one of the two IP addresses assigned to the VPG. Fixed Global IP addresses are unique to each VPG and are not shared between other Soracom accounts or other VPGs, so you can be confident that only authorized Air SIM devices are using the source IP address.
Please note: In order to enable the Fixed Global IP address option, you must apply by contacting Soracom. Rates for VPG and Fixed Global IP address apply.
I want to remotely access my Air SIM devices using an IP address
In some cases, you may want the ability to access your Air SIM devices remotely by connecting to them using an IP address (such as ssh or other remote management method).
Unfortunately, as public IP addresses are automatically reassigned frequently (resulting in a device's IP address potentially changing each time it reconnects to the network), Soracom does not support assigning a global or public IP address to each Air SIM device.
However, it is possible to connect your Air SIM devices to your organization's private network using SORACOM Canal, Door, or Direct, and then enable the Gate service to make your Air SIM devices accessible from within your private network.
For further information on how to access your Air SIM device from an external network, please refer to the following FAQ:
How do I connect to my Air SIM device from my private or external network?