diff --git a/quic/core/http/quic_spdy_session_test.cc b/quic/core/http/quic_spdy_session_test.cc
index 23611b3..20cebee 100644
--- a/quic/core/http/quic_spdy_session_test.cc
+++ b/quic/core/http/quic_spdy_session_test.cc
@@ -177,6 +177,11 @@
   bool ValidateAddressToken(absl::string_view /*token*/) const override {
     return true;
   }
+  const CachedNetworkParameters* PreviousCachedNetworkParams() const override {
+    return nullptr;
+  }
+  void SetPreviousCachedNetworkParams(
+      CachedNetworkParameters /*cached_network_params*/) override {}
 
   MOCK_METHOD(void, OnCanWrite, (), (override));
 
diff --git a/quic/core/http/quic_spdy_stream_test.cc b/quic/core/http/quic_spdy_stream_test.cc
index 50dc9ea..ce48043 100644
--- a/quic/core/http/quic_spdy_stream_test.cc
+++ b/quic/core/http/quic_spdy_stream_test.cc
@@ -161,6 +161,11 @@
   bool ValidateAddressToken(absl::string_view /*token*/) const override {
     return true;
   }
+  const CachedNetworkParameters* PreviousCachedNetworkParams() const override {
+    return nullptr;
+  }
+  void SetPreviousCachedNetworkParams(
+      CachedNetworkParameters /*cached_network_params*/) override {}
 
   MOCK_METHOD(void, OnCanWrite, (), (override));
 
diff --git a/quic/core/quic_crypto_client_stream.cc b/quic/core/quic_crypto_client_stream.cc
index fe6471f..31d96a3 100644
--- a/quic/core/quic_crypto_client_stream.cc
+++ b/quic/core/quic_crypto_client_stream.cc
@@ -160,17 +160,6 @@
   handshaker_->OnNewTokenReceived(token);
 }
 
-std::string QuicCryptoClientStream::GetAddressToken() const {
-  QUICHE_DCHECK(false);
-  return "";
-}
-
-bool QuicCryptoClientStream::ValidateAddressToken(
-    absl::string_view /*token*/) const {
-  QUICHE_DCHECK(false);
-  return false;
-}
-
 void QuicCryptoClientStream::SetServerApplicationStateForResumption(
     std::unique_ptr<ApplicationState> application_state) {
   handshaker_->SetServerApplicationStateForResumption(
diff --git a/quic/core/quic_crypto_client_stream.h b/quic/core/quic_crypto_client_stream.h
index daea001..688d603 100644
--- a/quic/core/quic_crypto_client_stream.h
+++ b/quic/core/quic_crypto_client_stream.h
@@ -11,6 +11,7 @@
 
 #include "quic/core/crypto/proof_verifier.h"
 #include "quic/core/crypto/quic_crypto_client_config.h"
+#include "quic/core/proto/cached_network_parameters_proto.h"
 #include "quic/core/quic_config.h"
 #include "quic/core/quic_crypto_handshaker.h"
 #include "quic/core/quic_crypto_stream.h"
@@ -73,6 +74,26 @@
     QUICHE_NOTREACHED();
     return false;
   }
+
+  std::string GetAddressToken() const override {
+    QUICHE_DCHECK(false);
+    return "";
+  }
+
+  bool ValidateAddressToken(absl::string_view /*token*/) const override {
+    QUICHE_DCHECK(false);
+    return false;
+  }
+
+  const CachedNetworkParameters* PreviousCachedNetworkParams() const override {
+    QUICHE_DCHECK(false);
+    return nullptr;
+  }
+
+  void SetPreviousCachedNetworkParams(
+      CachedNetworkParameters /*cached_network_params*/) override {
+    QUICHE_DCHECK(false);
+  }
 };
 
 class QUIC_EXPORT_PRIVATE QuicCryptoClientStream
@@ -257,8 +278,6 @@
                           ConnectionCloseSource source) override;
   void OnHandshakeDoneReceived() override;
   void OnNewTokenReceived(absl::string_view token) override;
-  std::string GetAddressToken() const override;
-  bool ValidateAddressToken(absl::string_view token) const override;
   HandshakeState GetHandshakeState() const override;
   void SetServerApplicationStateForResumption(
       std::unique_ptr<ApplicationState> application_state) override;
diff --git a/quic/core/quic_crypto_server_stream_base.h b/quic/core/quic_crypto_server_stream_base.h
index 967d6d1..0a2a63e 100644
--- a/quic/core/quic_crypto_server_stream_base.h
+++ b/quic/core/quic_crypto_server_stream_base.h
@@ -73,11 +73,6 @@
   // the resumption actually occurred.
   virtual bool ResumptionAttempted() const = 0;
 
-  virtual const CachedNetworkParameters* PreviousCachedNetworkParams()
-      const = 0;
-  virtual void SetPreviousCachedNetworkParams(
-      CachedNetworkParameters cached_network_params) = 0;
-
   // NOTE: Indicating that the Expect-CT header should be sent here presents
   // a layering violation to some extent. The Expect-CT header only applies to
   // HTTP connections, while this class can be used for non-HTTP applications.
diff --git a/quic/core/quic_crypto_stream.h b/quic/core/quic_crypto_stream.h
index 8206f35..056186a 100644
--- a/quic/core/quic_crypto_stream.h
+++ b/quic/core/quic_crypto_stream.h
@@ -21,6 +21,7 @@
 
 namespace quic {
 
+class CachedNetworkParameters;
 class QuicSession;
 
 // Crypto handshake messages in QUIC take place over a reserved stream with the
@@ -114,6 +115,16 @@
   // Called to validate |token|.
   virtual bool ValidateAddressToken(absl::string_view token) const = 0;
 
+  // Get the last CachedNetworkParameters received from a valid address token.
+  virtual const CachedNetworkParameters* PreviousCachedNetworkParams()
+      const = 0;
+
+  // Set the CachedNetworkParameters that will be returned by
+  // PreviousCachedNetworkParams.
+  // TODO(wub): This function is test only, move it to a test only library.
+  virtual void SetPreviousCachedNetworkParams(
+      CachedNetworkParameters cached_network_params) = 0;
+
   // Returns current handshake state.
   virtual HandshakeState GetHandshakeState() const = 0;
 
diff --git a/quic/core/quic_crypto_stream_test.cc b/quic/core/quic_crypto_stream_test.cc
index 093d245..fb1374f 100644
--- a/quic/core/quic_crypto_stream_test.cc
+++ b/quic/core/quic_crypto_stream_test.cc
@@ -68,6 +68,11 @@
   bool ValidateAddressToken(absl::string_view /*token*/) const override {
     return true;
   }
+  const CachedNetworkParameters* PreviousCachedNetworkParams() const override {
+    return nullptr;
+  }
+  void SetPreviousCachedNetworkParams(
+      CachedNetworkParameters /*cached_network_params*/) override {}
   HandshakeState GetHandshakeState() const override { return HANDSHAKE_START; }
   void SetServerApplicationStateForResumption(
       std::unique_ptr<ApplicationState> /*application_state*/) override {}
diff --git a/quic/core/quic_session_test.cc b/quic/core/quic_session_test.cc
index f55ac6e..81decdc 100644
--- a/quic/core/quic_session_test.cc
+++ b/quic/core/quic_session_test.cc
@@ -145,6 +145,11 @@
   bool ValidateAddressToken(absl::string_view /*token*/) const override {
     return true;
   }
+  const CachedNetworkParameters* PreviousCachedNetworkParams() const override {
+    return nullptr;
+  }
+  void SetPreviousCachedNetworkParams(
+      CachedNetworkParameters /*cached_network_params*/) override {}
   HandshakeState GetHandshakeState() const override {
     return one_rtt_keys_available() ? HANDSHAKE_COMPLETE : HANDSHAKE_START;
   }
diff --git a/quic/test_tools/quic_test_utils.h b/quic/test_tools/quic_test_utils.h
index e746ddb..e059f31 100644
--- a/quic/test_tools/quic_test_utils.h
+++ b/quic/test_tools/quic_test_utils.h
@@ -831,6 +831,11 @@
   bool ValidateAddressToken(absl::string_view /*token*/) const override {
     return true;
   }
+  const CachedNetworkParameters* PreviousCachedNetworkParams() const override {
+    return nullptr;
+  }
+  void SetPreviousCachedNetworkParams(
+      CachedNetworkParameters /*cached_network_params*/) override {}
   void OnConnectionClosed(QuicErrorCode /*error*/,
                           ConnectionCloseSource /*source*/) override {}
   HandshakeState GetHandshakeState() const override { return HANDSHAKE_START; }