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

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

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

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

IPv6 Header

Some ‘Next Header’ Values 2 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

Addressing As we saw yesterday, v4 is 32 bits, divided into 4 bytes / octets Each octet is expressed in base 10 - e.g. 128.4.32.101 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

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!

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

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

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!

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!

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

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

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) c.j.lord@ieee.org http://www.blueridgetechnc.com