Using a traditional exchange: Pros and cons Traditional exchanges compared. Once a payment method is linked, select Bitcoin or whatever cryptocurrency you plan on purchasing. Cumberland Mining is one of the leading OTC liquidity providers in the digital currency space. Due to this users may have a tough time making use of their large deposits. However, there is always a chance of your information being used, so it is important to be aware that it is possible. Enter your number, and Coinbase will text you a code.