diff --git a/docs/pom.xml b/docs/pom.xml
index ea1de046..b5c65aa6 100644
--- a/docs/pom.xml
+++ b/docs/pom.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 		 xmlns="http://maven.apache.org/POM/4.0.0"
-		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 	<parent>
 		<groupId>org.springframework.cloud</groupId>
diff --git a/pom.xml b/pom.xml
index ac65b0df..72b8c51f 100644
--- a/pom.xml
+++ b/pom.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 		 xmlns="http://maven.apache.org/POM/4.0.0"
-		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 
 	<groupId>org.springframework.cloud</groupId>
diff --git a/spring-cloud-gateway-core/pom.xml b/spring-cloud-gateway-core/pom.xml
index 17b26ab8..6538cbb0 100644
--- a/spring-cloud-gateway-core/pom.xml
+++ b/spring-cloud-gateway-core/pom.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 		 xmlns="http://maven.apache.org/POM/4.0.0"
-		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 
 	<parent>
diff --git a/spring-cloud-gateway-dependencies/pom.xml b/spring-cloud-gateway-dependencies/pom.xml
index bb5f4c5e..7a7c4c98 100644
--- a/spring-cloud-gateway-dependencies/pom.xml
+++ b/spring-cloud-gateway-dependencies/pom.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 		 xmlns="http://maven.apache.org/POM/4.0.0"
-		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 	<parent>
 		<artifactId>spring-cloud-dependencies-parent</artifactId>
diff --git a/spring-cloud-gateway-mvc/pom.xml b/spring-cloud-gateway-mvc/pom.xml
index 21fefa85..a0f2ffd9 100644
--- a/spring-cloud-gateway-mvc/pom.xml
+++ b/spring-cloud-gateway-mvc/pom.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 		 xmlns="http://maven.apache.org/POM/4.0.0"
-		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 
 	<artifactId>spring-cloud-gateway-mvc</artifactId>
diff --git a/spring-cloud-gateway-sample/pom.xml b/spring-cloud-gateway-sample/pom.xml
index 1f7f7628..62f96152 100644
--- a/spring-cloud-gateway-sample/pom.xml
+++ b/spring-cloud-gateway-sample/pom.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 		 xmlns="http://maven.apache.org/POM/4.0.0"
-		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 
 	<artifactId>spring-cloud-gateway-sample</artifactId>
diff --git a/spring-cloud-gateway-webflux/pom.xml b/spring-cloud-gateway-webflux/pom.xml
index cb25fef8..ceca2f4c 100644
--- a/spring-cloud-gateway-webflux/pom.xml
+++ b/spring-cloud-gateway-webflux/pom.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 		 xmlns="http://maven.apache.org/POM/4.0.0"
-		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 
 	<artifactId>spring-cloud-gateway-webflux</artifactId>
diff --git a/spring-cloud-starter-gateway/pom.xml b/spring-cloud-starter-gateway/pom.xml
index 21d22295..fd9e63a7 100644
--- a/spring-cloud-starter-gateway/pom.xml
+++ b/spring-cloud-starter-gateway/pom.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 		 xmlns="http://maven.apache.org/POM/4.0.0"
-		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 	<parent>
 		<groupId>org.springframework.cloud</groupId>
diff --git a/src/checkstyle/checkstyle-suppressions.xml b/src/checkstyle/checkstyle-suppressions.xml
index 9adff450..881f7187 100644
--- a/src/checkstyle/checkstyle-suppressions.xml
+++ b/src/checkstyle/checkstyle-suppressions.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0"?>
 <!DOCTYPE suppressions PUBLIC
 		"-//Puppy Crawl//DTD Suppressions 1.1//EN"
-		"http://www.puppycrawl.com/dtds/suppressions_1_1.dtd">
+		"https://www.puppycrawl.com/dtds/suppressions_1_1.dtd">
 <suppressions>
 	<suppress files=".*AbstractNameValueGatewayFilterFactory\.java" checks="LineLengthCheck"/>
 	<suppress files=".*AdhocTestSuite\.java" checks="LineLengthCheck"/>