Is simplified payment validation (SPV) decentralized?
Viz., when an SPV client wants to verify a payment, does it connect to a central server or to several random peers, checking that their Merkle tree traversals for the transaction to be verified all agree?
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Choose your Bitcoin wallet" from Bitcoin.org says (e.g., for GreenAddress's Android wallet) "Decentralized validation," which it describes as:
This wallet connects to a random server from a list. This means some trust in third parties is required when verifying payments. However, it is not as secure as a full node like
Bitcoin Core.
How is "connect[ing] to a random server from a list" decentralized?
However (e.g., for iOS's BreadWallet) it says "Simplified validation" instead, which it describes as:
This wallet uses SPV and the Bitcoin network. This means very little trust in third parties is required when verifying payments. However, it is not as secure as a full node like
Bitcoin Core.
(cf. the related Bitcoin StackExchange question)