diff --git a/OpenStack/base.md b/OpenStack/base.md
index 2e1da3b..cd0fdb0 100644
--- a/OpenStack/base.md
+++ b/OpenStack/base.md
@@ -6,5 +6,5 @@
 6. glance: 镜像服务
 7. ceilometer: 计量计费,监控
 8. heat: 编排服务
-9. 
+9. keystone: 身份认证
 10. ironic: 裸金属管理
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