学习计算机网络的时候看到了“节点本地”,“链路本地”,“站点本地”这三个词,百度了一下,只看到大家解释了“链路本地”和“站点本地”的意思,但好像没有人解释“节点本地”的含义。想请教一下大牛们,能系统地,简洁地解释一下三者的含义和区别吗?
看图会比看文字易懂,更直观,直接上图不废话。
node-local(interface-local), link-local和site-local.
node-local最早定义在rfc1884,https://tools.ietf.org/html/rfc1884
现在的名字叫interface-local,在rfc4291,https://tools.ietf.org/html/rfc4291
区别在于地址前缀
FF01::就是node-local
FF02::就是link-local
| 8 | 4 | 4 | 112 bits |
+------ -+----+----+---------------------------------------------+
|11111111|flgs|scop| group ID |
+--------+----+----+---------------------------------------------+
scop is a 4-bit multicast scope value used to limit the scope of
the multicast group. The values are:
0 reserved
1 node-local scope
2 link-local scope
3 (unassigned)
4 (unassigned)
5 site-local scope
6 (unassigned)
7 (unassigned)
8 organization-local scope
9 (unassigned)
应用上
node-local scope就是单机内的多播,用于一个node不同进程间的通信
link-local scope就理解成局域网的多播
site-local scope么广域网的多播