IPv6 Flashcards
global unicast address
globally unique and routable on internet, always starts with 200::1 /3 or 001 in binary. also always starts with a 2 or 3 in hex
what does SLA stand for in IPv6
site-level aggregator, it is analogous to a subnet and can also be called the Subnet ID
local unicast address
analogous to private addres in IPv4, always starts with FC00:: /7 followed by the subnet prefix
link-local address
automatically configured on an IPv6 interface, prefix of FE80:: /10 or 1111 1110 10 in binary, used in neighbor discovery processes and stateless autoconfiguration
What is an IPv4 compatible IPv6 address?
This is an IPv6 unicast address that has zeros in the high-order 96 bits of the address and an IPv4 address in the low-order 32 bits of the address. The format of an IPv4-compatible IPv6 address is 0:0:0:0:0:0:A.B.C.D or ::A.B.C.D.
IPv6 multicast address prefix
first octet is FF00::/8 1111 1111 second octet defines lifetime and scope
anycast address
created by assigning the same unicast address to multiple interfaces, the node must be configured to recognize it as an anycast address. Hosts cannot use anycast addresses and anycast addresses cannot be used as the source address for a packet.
EUI-64 Host ID
pads the 48 bit mac address of the device by inserting FFFE into the middle 16 bits and uses that as the host portion of the IPv6 address. Commonly used for phones gateways and routers
Stateless Autoconfiguration
node automatically configures its address by appending its 64 bit interface identifier to the 64 bit network prefix. This enables plug and play for devices on networks with IPv6 routers
Stateful Autoconfiguration
uses a DHCPv6 Server, enables record keeping for which hosts have which address unlike stateless autoconfiguration
default muticast groups for IPv6 interface
- Solicited-node multicast group FF02:0:0:0:0:1:FF00::/104 (for each unicast and anycast address that is assigned to the interface) - All-nodes link-local multicast group FF02::1 - All-routers link-local multicast group FF02::2
What is neighbor discovery used for in IPv6?
- Determining the data link layer address of a neighbor on the same link, like ARP does in IPv4 - Finding neighbor routers - Keeping track of neighbors
What is the command to configure stateless autoconfiguration on the router?
ipv6 address autoconfig [default] enter on a per interface basis. If the default keyword is added the router will advertise itself as the default gateway.
IPv6 routing protocols
RIPng (next generation) OSPFv3 EIGRP for IPv6 MP-BGP4
Steps to enable IPv6 routing
first enter command ipv6 unicast routing to enable the router forward ipv6 unicast packets, then enable ipv6 on each necessary interface with the ipv6 enable command
How to configure a static route in IPv6
ipv6 route *ipv6-network/ipv6-mask *outgoing_interface [ipv6-next-hop]
OSPFv3 multicast address
FF02::5 for OSPF routers FF02::6 for OSPF designated routers
main differences in OSPFv3
support for IPv6 In version 3, you assign the router ID, area ID, and link-state ID, which are all still 32-bit values but are no longer found using the IP address because an IPv6 address is 128 bits
Router(config)#ipv6 router ospf process-id:
Enables the OSPF routing process for IPv6. The process-id identifies the specific routing process and does not need to be the same on all routers in the OSPF routing domain.
Router(config-rtr)#router-id router-id:
The router uses the 32-bit value to select the router ID for OSPFv3 represented in dotted decimal notation.
Router(config-if)#ipv6 ospf process-id area area-id:
Enables the OSPFv3 routing process on an interface. The process-id identifies the specific routing process and must be the same as the process-id used to create the routing process in the ipv6 router ospf process-id command. The area-id is the area that must be associated with the OSPFv3 interface.
Router(config-rtr)#default-information originate:
Generates a default external route into the OSPFv3 routing domain.
When an IPv6 router sends a router advertisement, what is the destination multicast address?
FF02::1
unique local address
These are addresses similar to RFC 1918, “Address Allocation for Private Internets,” in IPv4 today In hexadecimal, site-local addresses begin with FE and then C to F for the third hexadecimal digit. So, these addresses begin with FEC, FED, FEE, or FEF.
