diff --git a/pom.xml b/pom.xml
index 345a0ef..fe15c2b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -37,7 +37,24 @@
             <artifactId>postgresql</artifactId>
             <version>42.7.3</version>
         </dependency>
-
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-oauth2-resource-server</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-security</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <optional>true</optional>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.security</groupId>
+            <artifactId>spring-security-test</artifactId>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>
diff --git a/src/main/java/de/anxietyprime/swajodel/security/JwtConverter.java b/src/main/java/de/anxietyprime/swajodel/security/JwtConverter.java
new file mode 100644
index 0000000..e59c25c
--- /dev/null
+++ b/src/main/java/de/anxietyprime/swajodel/security/JwtConverter.java
@@ -0,0 +1,60 @@
+package de.anxietyprime.swajodel.security;
+
+import org.springframework.core.convert.converter.Converter;
+import org.springframework.security.authentication.AbstractAuthenticationToken;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.security.oauth2.jwt.Jwt;
+import org.springframework.security.oauth2.jwt.JwtClaimNames;
+import org.springframework.security.oauth2.server.resource.authentication.JwtAuthenticationToken;
+import org.springframework.security.oauth2.server.resource.authentication.JwtGrantedAuthoritiesConverter;
+import org.springframework.stereotype.Component;
+
+import java.util.Collection;
+import java.util.Map;
+import java.util.Set;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+@Component
+public class JwtConverter implements Converter<Jwt, AbstractAuthenticationToken> {
+
+    private final JwtGrantedAuthoritiesConverter jwtGrantedAuthoritiesConverter = new JwtGrantedAuthoritiesConverter();
+
+    private final JwtConverterProperties properties;
+
+    public JwtConverter(JwtConverterProperties properties) {
+        this.properties = properties;
+    }
+
+    @Override
+    public AbstractAuthenticationToken convert(Jwt jwt) {
+        Collection<GrantedAuthority> authorities = Stream.concat(
+                jwtGrantedAuthoritiesConverter.convert(jwt).stream(),
+                extractResourceRoles(jwt).stream()).collect(Collectors.toSet());
+        return new JwtAuthenticationToken(jwt, authorities, getPrincipalClaimName(jwt));
+    }
+
+    private String getPrincipalClaimName(Jwt jwt) {
+        String claimName = JwtClaimNames.SUB;
+        if (properties.getPrincipalAttribute() != null) {
+            claimName = properties.getPrincipalAttribute();
+        }
+        return jwt.getClaim(claimName);
+    }
+
+    private Collection<? extends GrantedAuthority> extractResourceRoles(Jwt jwt) {
+        Map<String, Object> resourceAccess = jwt.getClaim("resource_access");
+        Map<String, Object> resource;
+        Collection<String> resourceRoles;
+
+        if (resourceAccess == null
+                || (resource = (Map<String, Object>) resourceAccess.get(properties.getResourceId())) == null
+                || (resourceRoles = (Collection<String>) resource.get("roles")) == null) {
+            return Set.of();
+        }
+        return resourceRoles.stream()
+                .map(role -> new SimpleGrantedAuthority("ROLE_" + role))
+                .collect(Collectors.toSet());
+    }
+}
diff --git a/src/main/java/de/anxietyprime/swajodel/security/JwtConverterProperties.java b/src/main/java/de/anxietyprime/swajodel/security/JwtConverterProperties.java
new file mode 100644
index 0000000..41acec0
--- /dev/null
+++ b/src/main/java/de/anxietyprime/swajodel/security/JwtConverterProperties.java
@@ -0,0 +1,19 @@
+package de.anxietyprime.swajodel.security;
+
+
+import lombok.Data;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.validation.annotation.Validated;
+
+@Data
+@Validated
+@Configuration
+@ConfigurationProperties(prefix = "jwt.auth.converter")
+
+
+public class JwtConverterProperties {
+
+    private String resourceId;
+    private String principalAttribute;
+}
diff --git a/src/main/java/de/anxietyprime/swajodel/security/SecurityConfig.java b/src/main/java/de/anxietyprime/swajodel/security/SecurityConfig.java
new file mode 100644
index 0000000..780ced2
--- /dev/null
+++ b/src/main/java/de/anxietyprime/swajodel/security/SecurityConfig.java
@@ -0,0 +1,33 @@
+package de.anxietyprime.swajodel.security;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.HttpMethod;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
+import org.springframework.security.config.http.SessionCreationPolicy;
+import org.springframework.security.web.SecurityFilterChain;
+
+@RequiredArgsConstructor
+@Configuration
+ @EnableWebSecurity
+public class SecurityConfig {
+
+    public static final String ADMIN = "admin";
+    public static final String USER = "user";
+    private final JwtConverter jwtConverter;
+    @Bean
+    public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
+        http.authorizeHttpRequests((authz) ->
+                authz.requestMatchers(HttpMethod.GET, "/messages/").permitAll()
+                        .anyRequest().authenticated());
+
+        http.sessionManagement(sess -> sess.sessionCreationPolicy(
+                SessionCreationPolicy.STATELESS));
+        http.oauth2ResourceServer(oauth2 -> oauth2.jwt(jwt -> jwt.jwtAuthenticationConverter(jwtConverter)));
+
+        return http.build();
+    }
+
+}
\ No newline at end of file
diff --git a/src/main/resources/application.properties b/src/main/resources/application.properties
index f440c33..50fef08 100644
--- a/src/main/resources/application.properties
+++ b/src/main/resources/application.properties
@@ -1 +1,5 @@
 spring.application.name=SWA-Jodel
+
+# Security Configuration
+spring.security.oauth2.resourceserver.jwt.issuer-uri=https://keycloak.anxietyprime.de/realms/Jodel
+spring.security.oauth2.resourceserver.jwt.jwk-set-uri=${spring.security.oauth2.resourceserver.jwt.issuer-uri}/protocol/openid-connect/certs