Hello!

I know that these are GSM frequency's
What is different between these 850/900/1700/1800/1900 frequency's ?
And does Mikrotik can support these frequency's there is some device with this option?

Thank you!

Anyone!
Can Mikrotik send and receive in these frequencies 850/900/1700/1800/1900/2100?

You can use the USB modems from a number of manufacturers. The supported list is here: http://wiki.mikrotik.com/wiki/Supported ... e#3G_cards
Note that that is a user edited list (not MT).