Transcript ADDRESSES!
IPv6 at Yale
Rick Beebe
Page 1
IPv what?
IPv4 = tcp/ip = IP address + protocols
130.132.35.53
Page 2
Why Do We Need IPv6?
MORE ADDRESSES!
•Depletion of IPv4 addresses
• 4 billion possible
• 1.8 billion mobile communication devices sold
in 2008
• IPv4 was never expected to last this long
• OSF.1 was going to take over
• CIDR and NAT gained us a decade
Page 3
Explosion of New Internet Appliances
Page 4
What Ever Happened to IPv5?
0
1
2
3
4
5
6
7
8
9
10-15
IP
IP
IP
IP
IPv4
ST
IPv6
CATNIP
Pip
TUBA
March 1977 version
January 1978 version
February 1978 version A
February 1978 version B
September 1981 version
Stream Transport
December 1998 version
IPng evaluation
IPng evaluation
IPng evaluation
unassigned
(deprecated)
(deprecated)
(deprecated)
(deprecated)
(current widespread)
(not a new IP, little use)
(formerly SIP, SIPP)
(TP/IX; deprecated)
(deprecated)
(deprecated)
Page 5
What Does IPv6 Offer?
•Fixes many of the shortcomings of IPv4
• More efficient routing
• More efficient packet processing
• Directed data flows
• Simplified network configuration
• No more NAT
• Security built in
and, of course, 128 bits of addresses
Page 6
What were the goals of a
new IP design?
• Expectation of a resurgence of “always-on” technologies
– xDSL, cable, Ethernet-to-the-home, Cell-phones, etc.
• Expectation of new users with multiple devices.
– China, India, etc. as new growth
– Consumer appliances as network devices
– (1015 endpoints)
• Expectation of millions of new networks.
– Expanded competition and structured delegation.
– (1012 sites)
Page 7
How big is 128 bits?
IPv4 is 32 bits: 4,294,967,296 addresses
IPv6 is 128 bits:
340,282,366,920,938,463,463,374,607,431,768,2
11,456 addresses
(Three hundred and forty undecillion, two hundred and eighty-two decillion, three
hundred and sixty-six nonillion, nine hundred and twenty octillion, nine hundred
and thirty-eight septillion, four hundred and sixty-three sextillion, four hundred
and sixty-three quintillion, three hundred and seventy-four quadrillion, six
hundred and seven trillion, four hundred and thirty-one billion, seven hundred
and sixty-eight million, two hundred and eleven thousand, four hundred and fiftysix.)
The smallest subnet allocation is /64 which
contains 4 billion IPv4 networks!
Page 8
What does an address look like?
Eight groups of four hexadecimal digits separated
by colons:
2604:b200:85a3:0000:0000:8a2e:0370:7334
• The hexadecimal digits are case-insensitive.
• An IPv6 address can be abbreviated with the following rules:
• Omit leading zeroes in a 16-bit value.
• Replace one group of consecutive zeroes by a double
colon.
Page 9
Compression rules
Fully qualified address
fe80 : 0000 : 0000 : 0000 : 0202 : b3ff : fe1e : 8329
Omit leading zeroes in a 16-bit value
fe80 : 0 : 0 : 0 : 202 : b3ff : fe1e : 8329
Replace one group of consecutive zeroes by a double colon
fe80 : : 202 : b3ff : fe1e : 8329
Below are the text representations of these addresses:
fe80:0000:0000:0000:0202:b3ff:fe1e:8329
fe80:0:0:0:202:b3ff:fe1e:8329
fe80::202:b3ff:fe1e:8329
Page 10
Yale IPv6 Address Scheme
2604 : b200
Yale prefix
Page 11
Yale IPv6 Address Scheme
2604 : b200 : 0000
Service/Router
• 0000 – infrastructure and p to p
• 0001 – Data Center subnets
• 0002 – Anger
• 0003 – College
• 0004 – Envy
• 0005 – Lust
• 0600 – access.yale.edu (VPN)
• 0609 – Med imaging firewall
etc
Page 12
Yale IPv6 Address Scheme
2604 : b200 : 0000 : 0000
VLAN ID in hex
Service ID
• 0 = data
• 1 = voice
Page 13
Yale IPv6 Address Scheme
2604 : b200 : 0000 : 0000 : 0202 : b3ff : fe1e : 8329
Interface address
Page 14
Yale IPv6 Address Scheme
2604 : b200 : 0000 : 0000 : 0202 : b3ff : fe1e : 8329
Easy calculator available at:
http://dno.med.yale.edu/ipv6.php
Page 15
IPv6 - Addressing Model
Addresses are assigned to interfaces
change from IPv4 model :
Interface 'expected' to have multiple addresses
Addresses have scope
Link Local
Site Local
Global
Global
Site-Local
Link-Local
Addresses have lifetime
Valid and Preferred lifetime
Page 16
Types of IPv6 Addresses
•
Unicast
–
–
•
Multicast
–
–
•
One address on a single interface
Delivery to single interface
Address of a set of interfaces
Delivery to all interfaces in the set
Anycast
–
–
Address of a set of interfaces
Delivery to a single interface in the set
No broadcast addresses
Page 17
Types of IPv6 Addresses
• Unicast and Anycast: first 3 bits 001
• Reserved: first 8 bits 0000 0000 (hex 00)
• Embedded IPv4 addresses in this space
• Multicast: first 8 bits 1111 1111 (hex ff)
•
•
•
•
•
Default route: ::/0
(0.0.0.0/0)
Loopback: ::1/128
(127.0.0.1)
Link Local: fe80::/10
(169.254.0.0/16)
Site Local: fc00::/7
(rfc1918)
IPv4: 0:0:0:0:0:FFFF:10.1.68.3 (::FFFF:10.1.68.3)
Page 18
Advantage: Efficient Routing
•
•
•
•
•
Header is larger, but simpler
Routers do not fragment
No checksum
TTL is now Hop Limit
Route aggregation
Page 19
Advantage: Multicast
• No more broadcasts
• All-Nodes packet sent to ff02::1
• Because Multicast is built-in, configuration is
significantly easier than in IPv4
Page 20
Advantage: SLAAC
Stateless Address Autoconfiguraton
• Host sends a router solicitation message
• Router sends back router advertisement
• Includes network, netmask and gateway
• May remove the need for DHCP servers
• Host generates its own host address
• May be NIC address
• May be randomly generated for privacy
Page 21
Advantage: Security
• IPSec encryption is built into the protocol
although its use is optional
• All implementations required to support
authentication and encryption headers (“IPsec”)
• Authentication separate from encryption for use
in situations where encryption is prohibited or
prohibitively expensive
• Key distribution protocols are under development
(independent of IP v4/v6)
• Support for manual key configuration required
Page 22
Where is it at Yale?
• Prefix assigned through ARIN:
•2604:b200::/32
• IPv6 enabled through virtually entire
infrastructure
• www.yale.edu reachable via IPv6:
• 2604:b200:6:65::10
• Building 25 4th floor
• Computer Science Zoo
• Sprague Hall
• IPv6 on DNS servers
Participated in World IPv6 Day!
Page 23
Thank you
Page 24