An individual (or government) who wants to bring down the Bitcoin network could conceivably broadcast a ton of junk/illegitimate transactions to the network thereby consuming the bandwidth and processing power necessary for the network to deal with legitimate transactions.
I understand Bitcoin has two protocols in place to address this vector of attack:
1) First and foremost it has each node verify all information received before relaying it to its peers. As such, an attacker would barley get past first base (i.e, legitimate node 1) to be able to cause catastrophic damage to the network at large
banscore (which effectively computes how bad a node is behaving. Once it reaches a certain critical threshold a neighboring node will stop receiving connections from that node/IP for a period of time)
My main question is: considering the fact that the government (or a government run entity) controls IP allocation isn't this solution completely reliant/dependent on a centralized entity to work effectively?