In the cryptocurrency world, Bitcoin holds the first place in terms of market cap and currency price, which makes it the first target and victim of attack attempts. Indeed, there are various attacks against cryptocurrencies in general and Bitcoin in particular, e.g., block withholding, transaction malleability and the Eclipse attack. The latter, allows an attacker to completely isolate a peer and to monopolize all permanent connections from/to the victim. However, in this attack, the non permanent connections, remains non monopolized by the attacker, which can disturb the attack success. In this paper, we propose (1) a characterization of the misbehavior mechanism applied by Bitcoin and its weaknesses; and (2) a new method to realize the Eclipse attack which monopolizes all the peer's connections, even the non permanent ones, with a minimal number of IP addresses. Our characterization and attack realization, were performed on the main Bitcoin network and on a real client.