Windows 7 / Networking

Understanding IPv6 Prefixes

An IPv6 prefix indicates the portion of the address used for routing (a subnet or a set of subnets as a summarized route) or for identifying an address range. IPv6 prefixes are expressed in a manner similar to the Classless Inter-Domain Routing (CIDR) notation used by IPv4. For example, 2001:DB8:3FA9::/48 might represent a route prefix in an IPv6 routing table.

In IPv4, CIDR notation can be used to represent individual unicast addresses in addition to routes and subnets. IPv6 prefixes, however, are used only to represent routes and address ranges, not unicast addresses. Unlike IPv4, IPv6 does not support variablelength subnet identifiers, and the number of high-order bits used to identify a subnet in IPv6 is almost always 64. It is thus redundant to represent the address in our example as 2001:DB8:3FA9::D3:9C5A/64; the /64 portion of the representation is understood.

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In this tutorial:

  1. Deploying IPv6
  2. Understanding IPv6
  3. Understanding IPv6 Terminology
  4. Understanding IPv6 Addressing
  5. Understanding IPv6 Prefixes
  6. Understanding IPv6 Address Types
  7. Understanding Unicast Addresses
  8. Identifying IPv6 Address Types
  9. Understanding Interface Identifiers
  10. Comparing IPv6 with IPv4
  11. Understanding IPv6 Routing
  12. How IPv6 Routing Works
  13. IPv6 Route Determination Process
  14. IPv6 Routing Table Structure
  15. Understanding ICMPv6 Messages
  16. Understanding Neighbor Discovery
  17. Understanding Address Autoconfiguration
  18. Understanding Name Resolution
  19. Understanding Name Queries
  20. Understanding Name Registration
  21. PTR Records and IPv6
  22. IPv6 Enhancements in Windows 7
  23. Summary of IPv6 Enhancements in Windows 7
  24. Configuring and Troubleshooting IPv6 in Windows 7
  25. Configuring IPv6 in Windows 7 Using the User Interface
  26. Configuring IPv6 in Windows 7 Using Netsh
  27. Other IPv6 Configuration Tasks
  28. Enabling or Disabling IPv6
  29. Disabling Random Interface IDs
  30. Resetting IPv6 Configuration
  31. Displaying Teredo Client Status
  32. Troubleshooting IPv6 Connectivity
  33. Planning for IPv6 Migration
  34. Blocking Teredo
  35. Understanding ISATAP
  36. Migrating an Intranet to IPv6
  37. Step 1: Upgrading Your Applications and Services
  38. Step 2: Preparing Your DNS Infrastructure
  39. Step 3: Upgrading Your Hosts
  40. Step 4: Migrating from IPv4-only to ISATAP
  41. Step 5: Upgrading Your Routing Infrastructure
  42. Step 6: Upgrading Your DHCP Infrastructure
  43. Step 7: Migrating from ISATAP to Native IPv6
  44. The Advantages of IPv6
  45. Address Resolution in IPv6