Update 计算机网络知识总结.md

Snailclimb · Snailclimb · commit 874a58bcf302 · 2021-07-13T23:25:21.000+08:00
diff --git a/docs/network/计算机网络知识总结.md b/docs/network/计算机网络知识总结.md
@@ -163,7 +163,7 @@
 
 ## 3. 数据链路层（Data Link Layer）
 
-![数据链路层](https://www.cloudflare.com/img/learning/ddos/glossary/open-systems-interconnection-model-osi/2-data-link-layer.svg)
+![数据链路层](https://guide-blog-images.oss-cn-shenzhen.aliyuncs.com/java-guide-blog/2-data-link-layer.svg)
 
 ### 3.1. 基本术语
 
