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OSPF区域拓扑

[英]OSPF area topology

原文 2020-03-19 06:09:49 5 1 networking/ routing/ telecommunication/ ospf

While reading about OSPF, I stumbled upon the following text:在阅读 OSPF 时，我偶然发现了以下文字：

An OSPF area hides the topology from another area but allows for the networks to be visible in other areas within the OSPF domain. OSPF 区域对另一个区域隐藏拓扑，但允许网络在 OSPF 域内的其他区域中可见。

If a topology change occurs (link flap or additional network added) within an area, all routers in the same OSPF area calculate the SPF tree again.如果一个区域内发生拓扑变化（链路抖动或添加额外网络），则同一 OSPF 区域内的所有路由器都会重新计算 SPF 树。 Routers outside of that area do not calculate the full SPF tree again but will perform a partial SPF calculation if the metrics have changed or a prefix is removed.该区域之外的路由器不会再次计算完整的 SPF 树，但如果度量已更改或前缀被删除，则会执行部分 SPF 计算。

Could someone please explain what view of an area is available to router outside the area and how partial calculation is enough for router outside that area.有人可以解释一下区域外的路由器可以使用什么区域视图，以及该区域外的路由器如何进行部分计算就足够了。

1 个解决方案

Okay, Finally I found the answer:好吧，我终于找到了答案：
Lets say we have two areas Area0 and Area1234.假设我们有两个区域 Area0 和 Area1234。
In that case Collection of (Type1 + Type2) LSAs that belong to particular network of Area1234 become 1 single summary LSA for Area0.在这种情况下，属于 Area1234 特定网络的 (Type1 + Type2) LSA 的集合成为 Area0 的 1 个单一汇总 LSA。
Summary LSA does not have any topology information, it only contain information that which ABR router to follow for a particular network that lies outside my Area.总结 LSA 没有任何拓扑信息，它只包含对于位于我的区域之外的特定网络要遵循哪个 ABR 路由器的信息。