IPv6

We are currently running out of IPv4 addresses, thus the need for IPv6. We should be out of addresses by February.

128 bits vs. 32 bit, 4x bigger than ipv4

• Unicast - 1 to 1
• Multicast - 1 to many - required in ipv6
• No Broadcast in IPV6. If you want to do a broadcast, you use multicast
• Anycast - 1 to nearest - auto sends the request to the nearest device in the network
• Simplified header. Same size as IPv4/Options
• ICMPv6/DHCPv6
• Neighbor discovery
• Auto-configuration
• IPSec mandatory
• Minimum of 2 IP addresses per interface

Addressing

• 128 bits split into 8 octets
• separated by colon
• Each Octet can be up to 4 digits
• In hex

URLs/URIs/SIP

• sip:bob@[2002::3:1]:5060
• localhost == ::1
• any == 0.0.0.0 == ::

Prefixes

• IPV4

 255.255.255.0 == /24

• IPv6

 fc00::/8
 2002::/3
 3fff:ffff::/32
 ::1/128
 loopback ::1/128

Prefix Type

link-local - fe80::/10 - cannot control it, defined by the switch you're connected to

• every interface will have link local
• each interface can have same IP
• resolved by using scope id

Scope ID

• Only applies to non-global IPs (link-local, etc)
• only valid for the machine making the request - defines what interface it will be talking out on
• post-fixed via %

 http://[fe80::1:2%2]:80/index.html
 http://[fe80::1:2]%2:80/index.html

Site-local - fec0::/10 - private network, whatever we want it to be

• equivalent to 192.168/16, 127/12, 10/8
• deprecated in favor of unique-local
• can still be used, useful for labs

unique-local@@ - fc00::/8 and fd00::/8

• fc00::/8 == alocation authority
• fd00::/8 == random assigned via rfc4193
• don't get more than one, reuse! 80 bits avail.
• Should block at edge
• Voxeo's random assigned - fd59:8f91:f52d::/48

Global - 2000::/3

• all publicly accessible IPs will be in this range
• expected all devices will be global (no NAT)

Tunnel IPv6 over IPv4 network

• 6 to 4 - requires edpoint to have public IP
• 2002::/16
• Teredo - encapsulate ipv6 packet in IPv4 UDP
• 2001::/16

IPv4 Mapped - ::ffff/96

• ::ffff:10.67.12.12
• Dual stack
• Some security concern

DNS

• 2 records you can have in IPV6
• AAAA - deprecated
• A6 - in place
• CNAME == DNAME