diff --git a/spring-session/src/main/java/org/springframework/session/web/http/CookieHttpSessionStrategy.java b/spring-session/src/main/java/org/springframework/session/web/http/CookieHttpSessionStrategy.java
index add722b1..21512e88 100644
--- a/spring-session/src/main/java/org/springframework/session/web/http/CookieHttpSessionStrategy.java
+++ b/spring-session/src/main/java/org/springframework/session/web/http/CookieHttpSessionStrategy.java
@@ -72,7 +72,7 @@ import org.springframework.util.Assert;
  * </p>
  *
  * <pre>
- * GET /messages/?u=1416195761178 HTTP/1.1
+ * GET /messages/?_s=1416195761178 HTTP/1.1
  * Host: example.com
  * Cookie: SESSION=f81d4fae-7dec-11d0-a765-00a0c91e6bf6
  * </pre>
@@ -87,7 +87,7 @@ import org.springframework.util.Assert;
  * <p>
  * To use the original session a request without the HTTP parameter u can be
  * made. To use the new session, a request with the HTTP parameter
- * u=1416195761178 can be used. By default URLs will be rewritten to include the
+ * _s=1416195761178 can be used. By default URLs will be rewritten to include the
  * currently selected session.
  * </p>
  *
@@ -150,7 +150,7 @@ import org.springframework.util.Assert;
 public final class CookieHttpSessionStrategy implements MultiHttpSessionStrategy, HttpSessionManager {
     static final String DEFAULT_ALIAS = "0";
 
-    static final String DEFAULT_SESSION_ALIAS_PARAM_NAME = "u";
+    static final String DEFAULT_SESSION_ALIAS_PARAM_NAME = "_s";
 
     private String cookieName = "SESSION";
 
diff --git a/spring-session/src/test/java/org/springframework/session/web/http/CookieHttpSessionStrategyTests.java b/spring-session/src/test/java/org/springframework/session/web/http/CookieHttpSessionStrategyTests.java
index 4257d078..1418cf03 100644
--- a/spring-session/src/test/java/org/springframework/session/web/http/CookieHttpSessionStrategyTests.java
+++ b/spring-session/src/test/java/org/springframework/session/web/http/CookieHttpSessionStrategyTests.java
@@ -132,49 +132,49 @@ public class CookieHttpSessionStrategyTests {
 
     @Test
     public void encodeURLNoExistingQuery() {
-        assertThat(strategy.encodeURL("/url", "2")).isEqualTo("/url?u=2");
+        assertThat(strategy.encodeURL("/url", "2")).isEqualTo("/url?_s=2");
     }
 
     @Test
     public void encodeURLNoExistingQueryEmpty() {
-        assertThat(strategy.encodeURL("/url?", "2")).isEqualTo("/url?u=2");
+        assertThat(strategy.encodeURL("/url?", "2")).isEqualTo("/url?_s=2");
     }
 
     @Test
     public void encodeURLExistingQueryNoAlias() {
-        assertThat(strategy.encodeURL("/url?a=b", "2")).isEqualTo("/url?a=b&u=2");
+        assertThat(strategy.encodeURL("/url?a=b", "2")).isEqualTo("/url?a=b&_s=2");
     }
 
     @Test
     public void encodeURLExistingQueryExistingAliasStart() {
-        assertThat(strategy.encodeURL("/url?u=1&y=z", "2")).isEqualTo("/url?u=2&y=z");
+        assertThat(strategy.encodeURL("/url?_s=1&y=z", "2")).isEqualTo("/url?_s=2&y=z");
     }
 
     @Test
     public void encodeURLExistingQueryExistingAliasMiddle() {
-        assertThat(strategy.encodeURL("/url?a=b&u=1&y=z", "2")).isEqualTo("/url?a=b&u=2&y=z");
+        assertThat(strategy.encodeURL("/url?a=b&_s=1&y=z", "2")).isEqualTo("/url?a=b&_s=2&y=z");
     }
 
     @Test
     public void encodeURLExistingQueryExistingAliasEnd() {
-        assertThat(strategy.encodeURL("/url?a=b&u=1", "2")).isEqualTo("/url?a=b&u=2");
+        assertThat(strategy.encodeURL("/url?a=b&_s=1", "2")).isEqualTo("/url?a=b&_s=2");
     }
 
     //
 
     @Test
     public void encodeURLExistingQueryParamEndsWithActualParamStart() {
-        assertThat(strategy.encodeURL("/url?xu=1&y=z", "2")).isEqualTo("/url?xu=1&y=z&u=2");
+        assertThat(strategy.encodeURL("/url?x_s=1&y=z", "2")).isEqualTo("/url?x_s=1&y=z&_s=2");
     }
 
     @Test
     public void encodeURLExistingQueryParamEndsWithActualParamMiddle() {
-        assertThat(strategy.encodeURL("/url?a=b&xu=1&y=z", "2")).isEqualTo("/url?a=b&xu=1&y=z&u=2");
+        assertThat(strategy.encodeURL("/url?a=b&x_s=1&y=z", "2")).isEqualTo("/url?a=b&x_s=1&y=z&_s=2");
     }
 
     @Test
     public void encodeURLExistingQueryParamEndsWithActualParamEnd() {
-        assertThat(strategy.encodeURL("/url?a=b&xu=1", "2")).isEqualTo("/url?a=b&xu=1&u=2");
+        assertThat(strategy.encodeURL("/url?a=b&x_s=1", "2")).isEqualTo("/url?a=b&x_s=1&_s=2");
     }
 
     //
@@ -197,17 +197,17 @@ public class CookieHttpSessionStrategyTests {
     @Test
     public void encodeURLExistingQueryExistingAliasStartDefaultAlias() {
         // relaxed constraint as result /url?&y=z does not hurt anything (ideally should remove the &)
-        assertThat(strategy.encodeURL("/url?u=1&y=z", "0")).doesNotContain("u=0&u=1");
+        assertThat(strategy.encodeURL("/url?_s=1&y=z", "0")).doesNotContain("_s=0&_s=1");
     }
 
     @Test
     public void encodeURLExistingQueryExistingAliasMiddleDefaultAlias() {
-        assertThat(strategy.encodeURL("/url?a=b&u=1&y=z", "0")).isEqualTo("/url?a=b&y=z");
+        assertThat(strategy.encodeURL("/url?a=b&_s=1&y=z", "0")).isEqualTo("/url?a=b&y=z");
     }
 
     @Test
     public void encodeURLExistingQueryExistingAliasEndDefaultAlias() {
-        assertThat(strategy.encodeURL("/url?a=b&u=1", "0")).isEqualTo("/url?a=b");
+        assertThat(strategy.encodeURL("/url?a=b&_s=1", "0")).isEqualTo("/url?a=b");
     }
 
     // --- getCurrentSessionAlias