1. Get Ready for the New Internet: IPv.6
Class 2: Features of IPv.4 Versus IPv.6
September 9, 2014
Charles J. Lord, PE President, Consultant, Trainer Blue Ridge Advanced Design and Automation

2. This Week’s Agenda
9/8 Background and Overview of IP4 / IP6 9/9 Features of IPv.4 Versus IPv.6 9/10 Addressing in IPv.6 9/11 IPv.6: Traffic and Routing 9/12 Co-existing and Adopting IPv.6 – The Challenges

3. This Week’s Agenda
9/8 Background and Overview of IP4 / IP6 9/9 Features of IPv.4 Versus IPv.6 9/10 Addressing in IPv.6 9/11 IPv.6: Traffic and Routing 9/12 Co-existing and Adopting IPv.6 – The Challenges

4. IPv4 vs IPv6
V6 is NOT “v4 plus” – totally new and not meant to be backward compatable
There are ways for both to exist – we will address these Friday
Bigger addresses means a bigger header – but the v6 header has been simplified
Less computation needed by routers if the packet is to be passed on to another router

5. IPv6 Header

6. Some ‘Next Header’ Values2
Internet Group Management Protocol (IGMPv4)—IPv4 support 4
IPv4 5
Stream Protocol (RFC 1819) 6
TCP 8
Exterior Gateway Protocol (EGP) 9
IGP—any private interior gateway (used by Cisco for their IGRP) 17
UDP 41
IPv6 43
Routing header 44
Fragmentation header 45
Interdomain Routing Protocol (IDRP) 46
Resource Reservation Protocol (RSVP) 47
General Routing Encapsulation (GRE) 50
Encapsulating Security Payload header 51
Authentication header 58
ICMPv6 59
No Next Header for IPv6

8. Addressing
As we saw yesterday, v4 is 32 bits, divided into 4 bytes / octets
Each octet is expressed in base e.g
In v6, our address space is 128 bits, expressed as 8 16-bit words, written in hex - e.g. 2001:db8:510:200:0:5efe:c0a8:1
Note that leading zeroes are not written

9. DHCP Dynamic Host Configuration Protocol
Used in v4 to assign mask and address
Alternative for hard-coded IP address
Not needed in v6 – new protocols for assigning addresses
More on this tomorrow!

10. NAT Network Address Translation
Allows traffic coming into a router at one IP address to be distributed over a separate sub-net, each with its own local IP address (usually in a address block set aside for local addresses
Allowed extension of the original 232 address space – an ISP could provide one address to a customer then the customer could have as many nodes as they wanted

11. NAT (cont)
NAT leads to some challenges for peer-to-peer, web / ftp servers, etc inside of a subnet where an outside node needs to find a specific node within the NAT subnet
IPv6 does away with NAT by assigning addresses within a subnet that
Has a high likelihood of being unique in the Internet
Is checked before this address is passed to the Net

12. ARP Address Resolution Protocol
Searches a subnet / link in v4 to find all nodes and assign an IP address to each link local address (typically a MAC address)
Replaced with Neighbor Discovery in v6 – much more on this on Thursday!

19. DNS Domain Name Server Functionality is similar in v4 and v6
DNSv6 allows both A records (v4) and AAAA (quad-A) records (v6)
A v6 DNS lookup searches only for AAAA records
As we will see Friday, only about 14% of the ‘top’ websites have AAAA records
NOTE! The existence of a AAAA record infers that the website is fully v6 operational!

20. TCP / UDP Primary data transmission protocols
TCP is very similar between v4 and v6
UDP – biggest change is that the checksum is now required in v6

23. This Week’s Agenda
9/8 Background and Overview of IP4 / IP6 9/9 Features of IPv.4 Versus IPv.6 9/10 Addressing in IPv.6 9/11 IPv.6: Traffic and Routing 9/12 Co-existing and Adopting IPv.6 – The Challenges

24. Please stick around as I answer your questions!
Please give me a moment to scroll back through the chat window to find your questions
I will stay on chat as long as it takes to answer!
I am available to answer simple questions or to consult (or offer in-house training for your company)