CH10: network privacy: drop BIP150/151

Those particular BIPs are abandoned.  BIP324 takes the place of BIP151,
but a lot of this section refers to authentication, which is not in
BIP324.  Also, this section mentions implementation, but BIP324 has not
been deployed as of this writing.

ch08.asciidoc

@@ -1149,14 +1149,13 @@ client.
 ((("Bitcoin network", "encrypted
 connections")))((("encryption")))((("authentication")))Most new users of
 Bitcoin assume that the network communications of a Bitcoin node are
-encrypted. In fact, the original implementation of bitcoin communicates
-entirely in the clear. While this is not a major privacy concern for
-full nodes, it is a big problem for SPV clients.
+encrypted. In fact, the original implementation of Bitcoin communicates
+entirely in the clear, as does the modern implementation of Bitcoin Core
+at the time of writing.
 
 As a way to increase the privacy and security of the Bitcoin P2P
-network, there are two solutions that provide encryption of the
-communications: _Tor Transport_ and _P2P Authentication and Encryption_
-with BIP-150/151.
+network, there is a solution that provides encryption of the
+communications: _Tor Transport_.
 
 ==== Tor Transport
 
@@ -1189,42 +1188,6 @@ You can find more instructions on running Bitcoin Core as a Tor hidden
 service in the Bitcoin Core documentation (_docs/tor.md_) and various
 online tutorials.
 
-==== Peer-to-Peer Authentication and Encryption
-
-((("Peer-to-Peer authentication and encryption")))((("bitcoin
-improvement proposals", "Peer Authentication (BIP-150)")))((("bitcoin
-improvement proposals", "Peer-to-Peer Communication Encryption
-(BIP-151)")))Two Bitcoin Improvement Proposals, BIP-150 and BIP-151, add
-support for P2P authentication and encryption in the Bitcoin P2P
-network.  These two BIPs define optional services that may be offered by
-compatible Bitcoin nodes. BIP-151 enables negotiated encryption for all
-communications between two nodes that support BIP-151. BIP-150 offers
-optional peer authentication that allows nodes to authenticate each
-other's identity using ECDSA and private keys. BIP-150 requires that
-prior to authentication the two nodes have established encrypted
-communications as per BIP-151.
-
-As of January 2017, BIP-150 and BIP-151 are not implemented in Bitcoin
-Core. However, the two proposals have been implemented by at least one
-alternative Bitcoin client named bcoin.
-
-BIP-150 and BIP-151 allow users to run SPV clients that connect to a
-trusted full node, using encryption and authentication to protect the
-privacy of the SPV client.
-
-Additionally, authentication can be used to create networks of trusted
-Bitcoin nodes and prevent Man-in-the-Middle attacks. Finally, P2P
-encryption, if deployed broadly, would strengthen the resistance of
-Bitcoin to traffic analysis and privacy-eroding surveillance, especially
-in totalitarian countries where internet use is heavily controlled and
-monitored.
-
-((("", startref="BNospv08")))((("", startref="privacy08")))((("",
-startref="Sprivacy08")))The standard is defined in
-https://github.com/bitcoin/bips/blob/master/bip-0150.mediawiki[BIP-150
-(Peer Authentication)] and
-https://github.com/bitcoin/bips/blob/master/bip-0151.mediawiki[BIP-151
-(Peer-to-Peer Communication Encryption)].
 
 === Transaction Pools