systemSessionFactory
                        .newRepositorySession(request)
                        .getConfigProperties()
                        .get("aether.priority.WagonTransporterFactory"));
        properties.remove("maven.resolver.transport");

        // illegal
        properties.setProperty("maven.resolver.transport", "illegal");
        request.setSystemProperties(properties);

    private static final String MAVEN_RESOLVER_TRANSPORT_AUTO = "auto";

    private static final String WAGON_TRANSPORTER_PRIORITY_KEY = "aether.priority.WagonTransporterFactory";

    private static final String APACHE_HTTP_TRANSPORTER_PRIORITY_KEY = "aether.priority.ApacheTransporterFactory";