diff --git a/generate4.xml b/generate4.xml
index f31799b2..c43cd522 100644
--- a/generate4.xml
+++ b/generate4.xml
@@ -16,7 +16,7 @@
       <option type="with" name="pkgconfigdir" default="${libdir}/pkgconfig" example="=DIR" unprefixed="true" substitute="true" description="Path to pkgconfig directory." data_type="path" />
       <option type="with" name="tests" default="yes" conditional="true" description="Compile with unit tests." />
       <option type="with" name="examples" default="yes" conditional="true" description="Compile with examples." />
-      <option type="with" name="icu" default="no" define="BOOST_HAS_ICU" substitute="true" value="-DWITH_ICU" description="Compile with International Components for Unicode." />
+      <option type="with" name="icu" default="no" define="WITH_ICU" substitute="true" value="-DWITH_ICU" description="Compile with International Components for Unicode." />
       <option type="enable" name="avx2" default="no" description="Compile with avx2 intrinsics (specifically -mavx -mavx2)." />
       <option type="enable" name="avx512" default="no" description="Compile with avx512 intrinsics (specifically -mavx512bw -mavx512f)." />
       <option type="enable" name="sse41" default="no" description="Compile with sse4.1 intrinsics (specifically -msse4.1)." />
@@ -339,17 +339,17 @@
 
   <repository name="libbitcoin-network" version="4.0.0" email="eric@voskuil.org" >
 
-    <package library="bitcoin-network" description="Bitcoin P2P Network Library" url="https://github.com/libbitcoin/libbitcoin-network" />
+    <package library="bitcoin-network" description="Bitcoin P2P Network Library" url="https://github.com/libbitcoin/libbitcoin-network" >
+      <flag value="@ssl@" />
+    </package>
 
     <configure>
       <option type="with" name="pkgconfigdir" default="${libdir}/pkgconfig" example="=DIR" unprefixed="true" substitute="true" description="Path to pkgconfig directory." data_type="path" />
       <option type="with" name="tests" default="yes" conditional="true" description="Compile with unit tests." />
+      <option type="with" name="ssl" default="yes" define="WOLFSSL_USER_SETTINGS" substitute="true" value="-DWOLFSSL_USER_SETTINGS" description="Compile with internal ssl." />
       <option type="enable" name="ndebug" default="yes" define="NDEBUG" description="Compile without debug assertions." />
       <option type="enable" name="shared" default="yes" define="BOOST_ALL_DYN_LINK" inherited="true" description="Required for dynamically linking boost test." />
 
-      <!-- WOLFSSL_USER_SETTINGS causes import of "user_settings.h". -->
-      <define name="WOLFSSL_USER_SETTINGS"/>
-      
       <dependency name="boost" version="1.86.0" />
       <dependency name="boost_unit_test_framework" option="tests" />
       <dependency name="bitcoin-system" version="4.0.0" />
@@ -393,6 +393,7 @@
       <product prefix="lib" path="src" uuid="564eb540-d6b6-425c-b8db-b0bee8970c18" >
         <library name="bitcoin-system" />
         <headers path="include" />
+        <!-- TODO: exclude if WITH_SSL not defined -->
         <headers path="include/bitcoin/ssl" />
         <sources path="src" />
       </product>
@@ -404,7 +405,9 @@
         <library name="bitcoin-network" />
         <library name="boost_unit_test_framework" />
         <headers path="include" />
+        <!-- TODO: exclude if WITH_SSL not defined -->
         <headers path="include/bitcoin/ssl" />
+        <!-- TODO: exclude if WITH_SSL not defined -->
         <headers path="test/ssl/wolfssl" />
         <sources path="test" />
       </product>
@@ -1587,7 +1590,6 @@
       <dependency name="boost" version="1.86.0" />
       <dependency name="boost_unit_test_framework" option="tests" />
       <dependency name="bash-completion" version="2.0.0" option="bash-completiondir" unprefixed="true" extract="completionsdir" default="${datadir}/bash-completion/completions" />
-
       <dependency name="bitcoin-node" version="4.0.0" />
 
       <!-- General flags -->
diff --git a/props/version4/import/libbitcoin-network.import.props b/props/version4/import/libbitcoin-network.import.props
index 81b0d3dc..2f5c4fee 100644
--- a/props/version4/import/libbitcoin-network.import.props
+++ b/props/version4/import/libbitcoin-network.import.props
@@ -11,15 +11,29 @@
     <PropertyPageSchema Include="$(MSBuildThisFileDirectory)libbitcoin-network.import.xml" />
   </ItemGroup>
 
+  <!-- Options -->
+
+  <PropertyGroup>
+    <Option-ssl>true</Option-ssl>
+  </PropertyGroup>
+
+  <!-- Messages -->
+
+  <Target Name="OptionInfo" BeforeTargets="PrepareForBuild">
+    <Message Text="Option-ssl        : $(Option-ssl)" Importance="high"/>
+  </Target>
+
   <!-- Linkage -->
 
   <ItemDefinitionGroup>
     <ClCompile>
       <AdditionalIncludeDirectories>$(ProjectDir)..\..\..\..\..\libbitcoin-network\include\;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <AdditionalIncludeDirectories>$(ProjectDir)..\..\..\..\..\libbitcoin-network\include\bitcoin\ssl\;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+
+      <!-- Prevent boost from seeing ssl includes when ssl is deselected  (requires external headers). -->
+      <AdditionalIncludeDirectories Condition="'$(Option-ssl)' == 'true'">$(ProjectDir)..\..\..\..\..\libbitcoin-network\include\bitcoin\ssl\;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <AdditionalOptions>/bigobj %(AdditionalOptions)</AdditionalOptions>
       <PreprocessorDefinitions Condition="'$(Linkage-libbitcoin-network)' == 'static' Or '$(Linkage-libbitcoin-network)' == 'ltcg'">BCT_STATIC;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <PreprocessorDefinitions>WOLFSSL_USER_SETTINGS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions Condition="'$(Option-ssl)' == 'true'">WOLFSSL_USER_SETTINGS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
     </ClCompile>
     <Link>
       <AdditionalDependencies Condition="'$(Linkage-libbitcoin-network)' != ''">libbitcoin-network.lib;%(AdditionalDependencies)</AdditionalDependencies>
@@ -35,4 +49,14 @@
       </AdditionalLibraryDirectories>
     </Link>
   </ItemDefinitionGroup>
+
+  <Target Name="WolfSSLSuppressions" BeforeTargets="ClCompile">
+    <ItemGroup>
+      <ClCompile Update="@(ClCompile)">
+        <!-- Exclude wolfssl test sources when ssl is deselected (requires external linkage). -->
+        <ExcludedFromBuild Condition="$([System.String]::new('%(RelativeDir)').StartsWith('..\..\..\..\test\ssl\')) And '$(Option-ssl)' == 'false'">true</ExcludedFromBuild>
+      </ClCompile>
+    </ItemGroup>
+  </Target>
+  
 </Project>
\ No newline at end of file
diff --git a/props/version4/import/libbitcoin-network.import.xml b/props/version4/import/libbitcoin-network.import.xml
index 7bcfea23..f7ff53dd 100644
--- a/props/version4/import/libbitcoin-network.import.xml
+++ b/props/version4/import/libbitcoin-network.import.xml
@@ -14,4 +14,16 @@
       <EnumValue Name="ltcg" DisplayName="Static using link time compile generation (LTCG)" />
     </EnumProperty>
   </Rule>
+  <Rule Name="libbitcoin-network-options-uiextension" PageTemplate="tool" DisplayName="Bitcoin Network Options" SwitchPrefix="/" Order="1">
+    <Rule.Categories>
+      <Category Name="ssl" DisplayName="ssl" />
+    </Rule.Categories>
+    <Rule.DataSource>
+      <DataSource Persistence="ProjectFile" ItemType="" />
+    </Rule.DataSource>
+    <EnumProperty Name="Option-ssl" DisplayName="Enable Embedded SSL" Description="Requires external SSL if not enabled." Category="ssl">
+      <EnumValue Name="false" DisplayName="No" />
+      <EnumValue Name="true" DisplayName="Yes" />
+    </EnumProperty>
+  </Rule>
 </ProjectSchemaDefinitions>
\ No newline at end of file
diff --git a/props/version4/import/libbitcoin-system.import.props b/props/version4/import/libbitcoin-system.import.props
index 59ce698b..6d9a890f 100644
--- a/props/version4/import/libbitcoin-system.import.props
+++ b/props/version4/import/libbitcoin-system.import.props
@@ -46,12 +46,9 @@
   <ItemDefinitionGroup>
     <ClCompile>
       <AdditionalIncludeDirectories>$(ProjectDir)..\..\..\..\..\libbitcoin-system\include\;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <!-- WITH_ICU always defined in Visual Studio builds. -->
       <!-- NOMINMAX enables use of std::min/max without conflict. -->
       <!-- WIN32_LEAN_AND_MEAN avoids inclusion of certain headers, winsock.h conflicts with boost and protocol use of winsock2.h. -->
-      <PreprocessorDefinitions>WITH_ICU;WIN32_LEAN_AND_MEAN;NOMINMAX;_WIN32_WINNT=0x0602;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <!-- Disable auto-linking for all boost-json and its dependency boost-container so they can be header only. -->
-      <PreprocessorDefinitions>BOOST_JSON_NO_LIB;BOOST_CONTAINER_NO_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32_LEAN_AND_MEAN;NOMINMAX;_WIN32_WINNT=0x0602;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions Condition="'$(Linkage-libbitcoin-system)' == 'static' Or '$(Linkage-libbitcoin-system)' == 'ltcg'">BC_STATIC;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions Condition="$(Configuration.IndexOf('Debug')) != -1">_CRTDBG_MAP_ALLOC;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <!-- Enable use of CPU intrinsics. -->
diff --git a/props/version4/project/libbitcoin-network/libbitcoin-network-test/libbitcoin-network-test.props b/props/version4/project/libbitcoin-network/libbitcoin-network-test/libbitcoin-network-test.props
index 25f34048..40720709 100644
--- a/props/version4/project/libbitcoin-network/libbitcoin-network-test/libbitcoin-network-test.props
+++ b/props/version4/project/libbitcoin-network/libbitcoin-network-test/libbitcoin-network-test.props
@@ -13,14 +13,16 @@
     <ClCompile>
       <AdditionalIncludeDirectories>$(ProjectDir)..\..\..\..\..\libbitcoin-network\test\ssl\wolfssl\;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <EnablePREfast>false</EnablePREfast>
-      <PreprocessorDefinitions>CERT_PREFIX=&quot;$(RepoRoot.Replace("\", "/"))test/ssl/vectors/&quot;;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+
+      <!-- Define CERT_PREFIX as the relative path to the /certs and /tests parent directory. -->
+      <PreprocessorDefinitions Condition="'$(Option-ssl)' == 'true'">CERT_PREFIX=&quot;$(RepoRoot.Replace("\", "/"))test/ssl/vectors/&quot;;%(PreprocessorDefinitions)</PreprocessorDefinitions>
     </ClCompile>
     <PostBuildEvent Condition="'$(DebugOrRelease)' == 'release'">
       <Command>"$(TargetPath)" --log_level=warning --run_test=* --show_progress=no --build_info=yes</Command>
     </PostBuildEvent>
   </ItemDefinitionGroup>
 
-  <Target Name="SuppressWarningsForWolfSSLFiles" BeforeTargets="ClCompile">
+  <Target Name="WolfSSLSuppressions" BeforeTargets="ClCompile">
     <ItemGroup>
       <ClCompile Update="@(ClCompile)">
         <AdditionalOptions Condition="$([System.String]::new('%(RelativeDir)').StartsWith('..\..\..\..\test\ssl\wolfssl\'))">/wd4005 /wd4189 /wd4245 /wd4267 /wd4701 /wd4702 /wd4703 %(AdditionalOptions)</AdditionalOptions>
diff --git a/props/version4/project/libbitcoin-network/libbitcoin-network/libbitcoin-network.props b/props/version4/project/libbitcoin-network/libbitcoin-network/libbitcoin-network.props
index 03d786e6..8b269d47 100644
--- a/props/version4/project/libbitcoin-network/libbitcoin-network/libbitcoin-network.props
+++ b/props/version4/project/libbitcoin-network/libbitcoin-network/libbitcoin-network.props
@@ -7,24 +7,44 @@
     <RunCodeAnalysis>false</RunCodeAnalysis>
   </PropertyGroup>
 
+  <!-- User Interface -->
+
+  <ItemGroup Label="BuildOptionsExtension">
+    <PropertyPageSchema Include="$(MSBuildThisFileDirectory)$(ProjectName).xml" />
+  </ItemGroup>
+
+  <!-- Options -->
+
+  <PropertyGroup>
+    <Option-ssl>true</Option-ssl>
+  </PropertyGroup>
+
   <!-- Configuration -->
 
   <ItemDefinitionGroup>
     <ClCompile>
       <AdditionalIncludeDirectories>$(RepoRoot)include\;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <AdditionalIncludeDirectories>$(RepoRoot)include\bitcoin\ssl\;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+
+      <!-- Prevent boost from seeing ssl includes when ssl is deselected  (requires external headers). -->
+      <AdditionalIncludeDirectories Condition="'$(Option-ssl)' == 'true'">$(RepoRoot)include\bitcoin\ssl\;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <AdditionalOptions>/bigobj %(AdditionalOptions)</AdditionalOptions>
       <EnablePREfast>false</EnablePREfast>
       <PreprocessorDefinitions Condition="'$(ConfigurationType)' == 'DynamicLibrary'">BCT_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions Condition="'$(ConfigurationType)' == 'StaticLibrary'">BCT_STATIC;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <PreprocessorDefinitions>WOLFSSL_USER_SETTINGS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions Condition="'$(Option-ssl)' == 'true'">WOLFSSL_USER_SETTINGS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
     </ClCompile>
   </ItemDefinitionGroup>
 
-  <Target Name="SuppressWarningsForWolfSSLFiles" BeforeTargets="ClCompile">
+  <Target Name="WolfSSLSuppressions" BeforeTargets="ClCompile">
     <ItemGroup>
       <ClCompile Update="@(ClCompile)">
         <AdditionalOptions Condition="$([System.String]::new('%(RelativeDir)').StartsWith('..\..\..\..\src\ssl\'))">/wd4189 /wd4245 /wd4267 /wd4701 /wd4702 /wd4703 %(AdditionalOptions)</AdditionalOptions>
+        
+        <!-- This is only used as an inlining header, so never compile it directly. -->
+        <ExcludedFromBuild Condition="$([System.String]::new('%(RelativeDir)').StartsWith('..\..\..\..\include\bitcoin\ssl\'))">true</ExcludedFromBuild>
+        
+        <!-- Exclude wolfssl sources when ssl is deselected (requires external linkage). -->
+        <ExcludedFromBuild Condition="$([System.String]::new('%(RelativeDir)').StartsWith('..\..\..\..\include\bitcoin\ssl\wolfcrypt\src\')) And '$(Option-ssl)' == 'false'">true</ExcludedFromBuild>
       </ClCompile>
     </ItemGroup>
   </Target>
@@ -51,9 +71,19 @@
     <Linkage-secp256k1>static</Linkage-secp256k1>
     <Linkage-libbitcoin-system>static</Linkage-libbitcoin-system>
   </PropertyGroup>
+  
+  <!-- Options -->
 
+  <PropertyGroup>
+    <Option-ssl>true</Option-ssl>
+  </PropertyGroup>
+  
   <!-- Messages -->
 
+  <Target Name="OptionInfo" BeforeTargets="PrepareForBuild">
+    <Message Text="Option-ssl        : $(Option-ssl)" Importance="high"/>
+  </Target>
+
   <Target Name="LinkageInfo" BeforeTargets="PrepareForBuild">
     <Message Text="Linkage-secp256k1 : $(Linkage-secp256k1)" Importance="high"/>
     <Message Text="Linkage-_system   : $(Linkage-libbitcoin-system)" Importance="high"/>
diff --git a/props/version4/project/libbitcoin-network/libbitcoin-network/libbitcoin-network.xml b/props/version4/project/libbitcoin-network/libbitcoin-network/libbitcoin-network.xml
new file mode 100644
index 00000000..195b9cca
--- /dev/null
+++ b/props/version4/project/libbitcoin-network/libbitcoin-network/libbitcoin-network.xml
@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="utf-8"?>
+<ProjectSchemaDefinitions xmlns="clr-namespace:Microsoft.Build.Framework.XamlTypes;assembly=Microsoft.Build.Framework">
+  <Rule Name="libbitcoin-network-uiextension" PageTemplate="tool" DisplayName="Bitcoin Network Options" SwitchPrefix="/" Order="1">
+    <Rule.Categories>
+      <Category Name="ssl" DisplayName="ssl" />
+    </Rule.Categories>
+    <Rule.DataSource>
+      <DataSource Persistence="ProjectFile" ItemType="" />
+    </Rule.DataSource>
+    <EnumProperty Name="Option-ssl" DisplayName="Enable Embedded SSL" Description="Requires external SSL if not enabled." Category="ssl">
+      <EnumValue Name="false" DisplayName="No" />
+      <EnumValue Name="true" DisplayName="Yes" />
+    </EnumProperty>
+  </Rule>
+</ProjectSchemaDefinitions>
\ No newline at end of file
diff --git a/props/version4/project/libbitcoin-system/libbitcoin-system/libbitcoin-system.props b/props/version4/project/libbitcoin-system/libbitcoin-system/libbitcoin-system.props
index a4c55f38..310b4f60 100644
--- a/props/version4/project/libbitcoin-system/libbitcoin-system/libbitcoin-system.props
+++ b/props/version4/project/libbitcoin-system/libbitcoin-system/libbitcoin-system.props
@@ -19,12 +19,9 @@
     <ClCompile>
       <AdditionalIncludeDirectories>$(RepoRoot)include\;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <EnablePREfast>false</EnablePREfast>
-      <!-- WITH_ICU always defined in Visual Studio builds. -->
       <!-- NOMINMAX enables use of std::min/max without conflict. -->
       <!-- WIN32_LEAN_AND_MEAN avoids inclusion of certain headers, winsock.h conflicts with boost and protocol use of winsock2.h. -->
-      <PreprocessorDefinitions>WITH_ICU;WIN32_LEAN_AND_MEAN;NOMINMAX;_WIN32_WINNT=0x0600;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <!-- Disable auto-linking for all boost-json and its dependency boost-container so they can be header only. -->
-      <PreprocessorDefinitions>BOOST_JSON_NO_LIB;BOOST_CONTAINER_NO_LIB;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32_LEAN_AND_MEAN;NOMINMAX;_WIN32_WINNT=0x0600;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions Condition="'$(ConfigurationType)' == 'DynamicLibrary'">BC_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions Condition="'$(ConfigurationType)' == 'StaticLibrary'">BC_STATIC;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <PreprocessorDefinitions Condition="$(Configuration.IndexOf('Debug')) != -1">_CRTDBG_MAP_ALLOC;%(PreprocessorDefinitions)</PreprocessorDefinitions>