全方位解读服务网格（Service Mesh）的背景和概念

{"type":"doc","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"一直以来“微服务”都是一个热门的词汇，在各种技术文章、大会上，关于微服务的讨论和主题都很多。对于基于 Dubbo、SpringCloud 技术体系的微服务架构，已经相当成熟并被大家所知晓，但伴随着互联网场景的复杂度提升、业务快速变更以及快速响应，如何快速、稳定、高效的应对变幻莫测的业务市场需求，这类技术体系（如：Spring 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相关组件版本","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"升级","attrs":{}},{"type":"text","text":"时的烦恼么？为了使用新版本中的某个特性，或者解决旧版本中存在的漏洞,Spring Cloud 版本升级屡见不鲜，一不留神就会出现版本依赖冲突、启动不了等等问题，升级完还得安排测试人员测试验证。技术含量不高，但确实招人烦啊。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"再完美的程序，也避免不了零 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结合，并在业务中更好的深度融合，对于大部分开发者而言都是一个高曲线的学习过程。","attrs":{}}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"多语言支持受限微服务提倡不同组件可以使用最适合它的语言开发，但是传统微服务框架，如 Spring Cloud 则是 Java 的天下，多语言的支持难度很大。这也就导致在面对异构系统对接时的无奈，或选择退而求其次的方案了。","attrs":{}}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"老旧系统维护难面对老旧系统，很难做到统一维护、治理、监控等，在过度时期往往需要多个团队分而管之，维护难度加大。","attrs":{}}]}]}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"上述这些问题都是在所难免，我们都知道技术演进来源于实践中不断的摸索，将功能抽象、解耦、封装、服务化。 随着传统微服务架构暴露出的这些问题，将迎来新的挑战，让大家纷纷寻找其他解决方案。","attrs":{}}]},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"1.3 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的概念和存在的意义，让我们我们来回顾一下这一演进过程中的四个阶段。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/55/5589876c06fe35ce4878833fb97f3ecd.png","alt":null,"title":"","style":[{"key":"width","value":"100%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"bulletedlist","content":[{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"耦合阶段","attrs":{}},{"type":"text","text":"：高度耦合、重复实现、维护困难，在耦合架构设计中体现的最为突出，单体架构就是典型的代表。","attrs":{}}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"公共 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