Configuring IPv6

Dual-stack routing
  • Dual-stack IPv4 and IPv6
    • Run both at the same time
    • Interfaces will be assigned multiple address types
  • IPv4
    • Configured with IPv4 addresses
    • Maintains an IPv4 routing table
    • Uses IPv4 dynamic routing protocols
  • IPv6
    • Configured with IPv6 addresses
    • Maintains a separate IPv6 routing table
    • Uses IPv6 dynamic routing protocols
Tunneling IPv6
  • 6 to 4 addressing
    • Send IPv6 over an existing IPv4 network
    • Creates an IPv6 based on the IPv4 address
    • Requires relay routers
      • IP protocol 41 - a transition technology
    • No support for NAT
  • 4in6
    • Tunnel IPv4 traffic on an IPv6 network
Teredo/Miredo
  • Tunnel IPv6 through NATed IPv4
    • End-to-end IPv6 through an IPv4 network
    • No special IPv6 router needed
    • Temporary use
      • We'll have IPv6 native networks soon (?)
  • Miredo - Open-source Teredo for Linux,
  • BSD Unix, and Mac OS X
    • Full functionality
NDP (Neighbor Discovery Protocol)
  • No broadcasts!
    • Operates using multicast over ICMPv6
  • Neighbor MAC Discovery
    • Replaces the IPv4 ARP
  • SLAAC (Stateless Address Auto Configuration)
    • Automatically configure an IP address without a DHCP server
  • DAD (Duplicate Address Detection)
    • No duplicate IPs!
  • Discover routers
    • Router Solicitation (RS) and Router Advertisement (RA)
Finding Router
  • ICMPv6 adds the Neighbor Discovery Protocol
  • Routers also send unsolicited RA messages
    • From the multicast destination of ff02::1
  • Transfers IPv6 address information, prefix value, and prefix length, etc.
    • Sent as a multicast
  • Neighbor Advertisement (NA)
Howdy Neighbor
  • There's no ARP in IPv6
    • So how do you find out the MAC address of a device?
  • Neighbor Solicitation (NS)
    • Sent as a multicast
  • Neighbor Advertisement (NA)

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