Bitcoin developers are always looking to add new features and improvements to the many available wallet solutions. The introduction of committed bloom filters will be a significant milestone for privacy as the BIP37 SPV solution needs to be reworked.
Committed Bloom Filters Versus BIP37 SPV
For Bitcoin users who have been embracing the lightweight client model, there are some issues associated with BIP37 SPV in its current implementation. First of all, the originally anticipated levels of privacy will not be achieved through BIP37 SPV wallet support. The probabilistic nature of bloom filters offers no privacy whatsoever, and a wrongful implementation of this technology will only make matters significantly worse.
Secondly, there are mounting concerns over the CPU usage required for Bitcoin lightweight clients, which are often used as network nodes. Moreover, this causes a DDoS risk, as clients can continuously request taxing blocks, causing the client to reprocess the same block over and over again.
But that is not all, as lightweight wallet clients using BIP37 SPV will validate outputs, which does not necessarily reflect the output has been spent today. Additionally, all BIP37 SPV lightweight wallet clients on the Bitcoin network can be DDoS’ed by other network nodes