Address Scope Figure 2-3 IPv6 Address Scopes Global Unique Local Link Local
Address Scope
Global Unicast Addresses Routable and reachable across the Internet Identified by their three high-level bits set to001(2000:/3) Network ID ISP Site LAN Host 3 29 Bits 16Bits、16Bits 64 Bits Global Prefix SLA LAN Interface ID 001 1/32 /48 /64
Global Unicast Addresses ◼ Routable and reachable across the Internet ◼ Identified by their three high-level bits set to 001 (2000::/3)
Global routing prefix ▣service provider ■ Site level aggregator Customer of service provider ■LAN ID Individual networks in customer site
◼ Global routing prefix service provider ◼ Site level aggregator Customer of service provider ◼ LAN ID Individual networks in customer site
Unique Local Unicast Addresses Analogous to private IPv4 addresses Used for local communications,inter-site VPNs,and so forth Not routable on the Internet(routing would require IPv6 NAT) Figure 2-5 Unique Local Unicast Address Format -128 Bits- 1 Global ID 40 Bits Interface ID 1111110 Subnet ID ED00:/7 16 Bits 7 Bits 1 Bit:L=1 Locally assigned;L=0 Future Use
Unique Local Unicast Addresses ◼ Analogous to private IPv4 addresses ◼ Used for local communications, inter-site VPNs, and so forth ◼ Not routable on the Internet (routing would require IPv6 NAT)
Subnet IDs using a hierarchical addressing plan to allow for route summarization
◼ Subnet IDs using a hierarchical addressing plan to allow for route summarization