I am a newer to Ubuntu. In my network manager the link Enable Mobile Broadband found unchecked.I can not enable it.So I can not connect my BSNL cdma 1x USB modem successfully.
The majority of the ubuntu distributions (even plain ubuntu), can handle Mobile Broadband modems with no problems. But in my experience with some modems (ZTE and Huawei) the availability to use the Broadband modem is based on the behaviour of the modem itself, which can be handled by the majority of the systems as both: broadband modem or usb CD-ROM. This is caused by the need of some vendors to include the drivers and applications in the same item.
In ubuntu you may try to eject the modem (which should be in the desktop or in your mounted devices area at: /media/) and after a few seconds, the item will be recognized as a modem and not a CD nor USB memory.
If everything happens as we expect, then you will be able to use your modem and get your connection.
REMEMBER: Just "eject" the device, DON'T unmount, which shall result in the unavailability of getting access to the device.