标题: ipv6组播地址中的问题 [打印本页] 作者: Clark.Ho 时间: 2006-04-12 14:50 标题: ipv6组播地址中的问题 在组播地址的说明中,对于scop字段的说明中，其中的1 node-local scop 和5 site-local scop 有什么区别？
原文如下：
An IPv6 multicast address is an identifier for a group of nodes. A
node may belong to any number of multicast groups. Multicast
addresses have the following format:
| 8 | 4 | 4 | 112 bits |
+------ -+----+----+---------------------------------------------+
|11111111|flgs|scop| group ID |
+--------+----+----+---------------------------------------------+
11111111 at the start of the address identifies the address as
being a multicast address.
+-+-+-+-+
flgs is a set of 4 flags: |0|0|0|T|
+-+-+-+-+
The high-order 3 flags are reserved, and must be initialized to
0.
T = 0 indicates a permanently-assigned ("well-known") multicast
address, assigned by the global internet numbering authority.
T = 1 indicates a non-permanently-assigned ("transient")
multicast address.
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)
A (unassigned)
B (unassigned)
C (unassigned)作者: firebird 时间: 2006-04-12 15:08
Currently, the following regions (scopes) are defined:
· ffx1: node−local, packets never leave the node.
· ffx2: link−local, packets are never forwarded by routers, so they never leave the specified link.
· ffx5: site−local, packets never leave the site.
·ffx8: organization−local, packets never leave the organization (not so easy to implement, must becovered by routing protocol).
· ffxe: global scope.
· others are reserved作者: Clark.Ho 时间: 2006-04-12 15:28
thank you for your answer.
but i want to know what is the site,and what is the node ?
How to distinguish them?作者: firebird 时间: 2006-04-12 17:10
留个EMAIL，我发给你两个文件你看下，我具体也不太清楚。作者: wonderliang 时间: 2006-04-12 21:27
我记得不是很清楚了