If I send 4mbps of data to a friend with 4mbps connection, will I DDoS him?

Suppose my friend has a connection of 4mbps. If I just send him 4mpbs of random data with my server, wouldn't it block his connection? Even if the router has firewalls and closed ports, isn't enough for me to send random data continuosly to his router, in order to block it?

I've found some scripts on the internet (like this) and I tried to block my own connection with my server, but nothing happened.