Category: IPv6

• Unicast:  One-to-one.
• Multicast: One-to-many.
• Anycast: One-to-closest.

• Link-local scope address:  layer2 domain
• Unique / Site-local scope address: Organization
• Global scope address: Internet

(more…)

• Transition technique designed to allow native IPv6 hosts to access IPv4-only content.
  • (Translation technique not a tunneling technique).
• Primarily used to allow v6 hosts to initiate connections to IPv4 content.
  • Mechanisms do exist to allow the reverse.
• Stateful and stateless versions.
  • stateful can use any prefix
  • stateless has restriction on prefix

NAT64 and DNS64 co-existance.

1. IPv6 host sends AAAA DNS Query
2. DNS64 server tries AAAA lookup and fails
3. DNS64 server successfully resolves IPv4 address
4. DNS64 server generates AAAA DNS response of <IPv6 prefix:IPv4 adress> and sends it back to the client.

(more…)

• point-to-point tunnels
• MCT ( manually configured tunnel )
• GRE ( Generic Routing Encapsulation )

• Virtual point-to-point between two IPv4 routers
• IPv6 iGP routing protocols can run over these virtual links.

(more…)

Similarities to IPv4

• Redistribution takes routes from the IP routing table, not from the iGP databases.
• Route maps can be used for filtering, metrics, route tags.
• Admnistrative distance has not changed.
• Options to prevent routing loops; Administrative distance, route tags, filtering.
• Syntax is the same.

Differences to IPv4

• Supported “match” commands in route-maps vary on iGP
  • OSPF/RIP cannot match op “route-type” with a Route-map
    • EIGRP has no problems using “route-type”
  • Route-map matching IPv6 ACLs must have IPv6 prefix as source portion and “any” as destination of ACL.
• IPv6 redistribute connected does not include interfaces running the iGP;
  • redistribute include-connected

RIPng

• UPD port number 521
• No autosummarization for IPv6
• Destination address FF02::9
• Link-Local next-hops
• IPv6 uses IPv6 AH/ESP Authentication
• Enable it on the interface
  • ipv6 rip CCNP enable fa0/0
• No network command

EIGRP IPv6

• EIGRP uses the neighbor’s link local address as the next-hop
• Destination FF02::AA
• Authentication relies on the IPv6 built-in authentication nad privacy
• IPv4 defaults to auto summarization, IPv6 doesn’t
  • ipv6 unicast-routing
  • ipv6 route eigrp 100
  • (config-if)#ipv6 eigrp 100
  • eigrp router-id RID

(more…)