IPV4-IPV6过渡技术之6to4隧道
IPV4-IPV6过渡技术之6to4隧道_IPV4 (2012-12-14 14:06:22)
1、6to4 tunnel编址
在IPV6全局单播地址中，有一段地址保留给了6to4的tunnel（IANA规定，http://www.ietf.org/assignments/ipv6-unicast-address-assignments/ipv6-unicast-address-assignments.xml），地址范围为2002::/16，6to4中用到的位2002::/48（融入了IPV4的32bit)地址网段这是在6to4tunnel中要利用到的地址，并且一定是要用此地址网段。(RFC3056)
 
   The IANA has permanently assigned one 13-bit IPv6 Top Level
   Aggregator (TLA) identifier under the IPv6 Format Prefix 001 [AARCH,
   AGGR] for the 6to4 scheme.Its numeric value is 0x0002, i.e., it is
   2002::/16 when expressed as an IPv6 address prefix.
The subscriber site is then deemed to have the following IPv6 address
   prefix, without any further assignment procedures being necessary:
Prefix length: 48 bits
      Format prefix: 001
      TLA value: 0x0002
      NLA value: V4ADDR
This is illustrated as follows:
      |  3   |     13   |        32         |     16    |              64 bits                |
     +----- +----------+----------------+----------+-------------------------------+
     |FP   |    TLA   | V4ADDR     | SLA ID |         Interface ID             |
     |001|0x0002|                      |             |                                           |
     +----- +----------+----------------+----------+-------------------------------+
Thus, this prefix has exactly the same format as normal /48 prefixes
   assigned according to [AGGR].  It can be abbreviated as
   2002:V4ADDR::/48.  Within the subscriber site it can be used exactly
   like any other valid IPv6 prefix, e.g., for automated address
   assignment and discovery according to the normal mechanisms such as
   [CONF, DISC], for native IPv6 routing, or for the "6over4" mechanism
   [6OVER4].
 
 
2、6to4 tunnel细节；
 
6to4tunnel不仅适用在两个ipv6孤岛穿越IPV4核心进行通信的路由器环境中，而且还适用于主机路由器环境、路由器到主机等环境。为了和前面一致，还是使用下图；
 
 
IPV4-IPV6过渡技术之6to4隧道_IPV6_02
 
 

 

IPV4-IPV6过渡技术之6to4隧道_IPV4_03