Is FXTM an ECN broker?

Yes, FXTM is an ECN broker. 

ECN stands for "electronic communication network" and refers to an automated component of trading that connects individual traders to liquidity providers including banks, brokerages and even other traders. This process provides access to the financial markets to individuals with any type of trading account and regardless of their balance size. 

An ECN broker is usually a No Dealing Desk (NDD) broker, which means that the clients' orders do not pass through a Dealing Desk, which enables execution in a direct connection between the parties. 

FXTM provides an ECN account. They also have included an article giving detailed introduction about ECN broker in their educational resources.