Introduction to IPv6 Katherine Douglas, Instructor Herndon Career Center Local Cisco Networking Academy Before we start… Please write down the following Key Terms on a blank piece of notebook paper leaving a small underline before and after each word. Label your paper IPv6 Pre/Post Concept Check. _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ IPv4 IPng IPv6 Classful address NAT Scalability VLSM CIDR Hierarchy Aggregation Successive Unicast Multicast Anycast _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ More key terms… _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ Scope of address Type of address IPv4-Compatible IPv4-Mapped IANA ARIN RIPE NCC APNIC AfriNIC ISP Dual-Stack Tunneling Translation Node Router Host Upper layer Link Interface Address Packet _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ _____ Pre Check of Knowledge 1. Rate yourself as to your perceived knowledge of these key words. 2. Assess how much you already know about these terms by placing a (+), a check (√), or a zero (0) in the space to the left of each word. Plus (+) = Expert Check (√) = Heard of it Zero (0) = Have not heard of it. We will do a Post Check at the end of today’s lesson. IPv6 Defined Internet Protocol version 6 Originally known as IPng, or IP Next Generation Network Layer protocol for packet switched networks Successor of IPv4 which supports about 4.3 billion addresses (232 addresses) IPv6 increased the number of addresses to (2128 addresses) Useful for mobility, QoS, and privacy extension WOW! 128 2 Addresses 340,282,366,920,938,000,000,000,000,000,000,000,000 340*1036 million, billion, trillion, what?.... NO!! It’s 340 undecillion in America or 340 sextillion in Europe Picture This! 430 quintillion addresses per sq. inch of the Earth’s Surface Quintillion = American term for 1018 Trillion = European term for 1018 That’s more than a trillion addresses per square centimeter of surface on the planet Each person on Earth could be assigned 7 unique addresses for every atom in his or her body! (assuming 1,027 atoms per human for roughly 6.5 billion people alive today) 252 for every star in the known universe! Questions to ponder? Do we really need this extremely large address space? Is this overkill? How will this effect our routers and our routing tables? What about overhead on equipment and on our bandwidth? What happened to IPv5? Did we skip a version? Examine the Facts IPv6 longer address length is needed for: Routing Aggregation Autoconfiguration of Addresses Improved scalability for multicast routing More efficient forwarding Greater flexibility to introduce new options Flow labeling to aide in QoS and special handling Benefits Easier allocation of address blocks Flexibility of ISPs to subdivide blocks for customers Organizations can subdivide blocks for internal networks Unique IP addresses facilitate End-To-End (E2E) connections Embedded Quality of Service (QoS) to support services like VoIP & IP Video Okay, so what happened to IPv5? IPv5 was NOT a successor to IPv6 Known as Internet ST (Stream Protocol) Intended to be a connection oriented complement to IPv4 Experimental protocol….Not in public use IPv4 vs IPv6 IPv4 Fewer total addresses Address depletion Scalability problems Exponential growth of Internet & number of routes Need private addressing and Network Address Translation (NAT) Provides IP for ISPs, companies, governments, and educational institutions Represented in dotted decimal notation IPv6 Does not need NAT More addresses with additional levels of hierarchy to support network growth Increased bandwidth overhead Requires DNS Difficult to memorize addresses Provides IP for ALL citizens! NO BROADCASTS! Represented in Colon Hexadecimal notation Backward compatible with IPv4 What’s driving the need?? Internet growth Mobile devices PDAs Mobile phones Tablet PCs Gaming Voice/Video Security Monitoring Appliances Medical Imaging Animal Tags Media Services Traffic Control Planes Automobiles Hotspots IPv6 Header Fields Version – version 6 (4 bits) Traffic Class – packet priority (8 bits) where source provides congestion or non-congestion control Flow Label – QoS management (20 bits) Payload Length – when set to zero, the option is “jumbo payload” or hop-by-hop which carries optional info that must be examined by every node (16 bits) Next Header – next encapsulated protocol compatible with IPv4 protocol field. (8 bits) Hop Limit – replaces the TTL (time to live) in IPv4 (8 bits) Source Address and Destination Address – (128 bits each) IPv6 Addresses Unicast – identifies a single interface on a single node. A unicast packet is delivered to the identified single interface. Multicast - identifies a set of interfaces that belong to different nodes. A multicast packet is delivered to all identified interfaces. Anycast – a global unicast address that is assigned to a set of interfaces that belong to different nodes. An anycast packet is delivered to the closest interface. Broadcast – Not in IPv6!!! IPv6 Special Addresses Reserved – reserved by IETF for special uses. First eight bits are 00000000. IPv4 embedded addresses use this block. Private – private addresses are local to a particular site or company network and are never routed outside that network. First nine bits are: 111111101 Loopback – used for testing the “loop back” of the device. 0:0:0:0:0:0:0:1/128 or ::1/128 Unspecified – used in the source field when a host is seeking to have its IP address configured. All 128 bits are zeroes noted as 0:0:0:0:0:0:0:0, ::, or 0::0. IPv6 Addressing Format Written in Colon Hexadecimal Notation Typically see the IPv6 Address followed by a slash “/” for the Prefix Length Prefix Length is the number of leftmost bits that represent the prefix, written in slash notation just like CIDR in IPv4 IPv6 Ex: 2001:c001:c15c::/48 Two colons “::” represent successive leading zeroes Example: 2001:0:0:0:260:97FF:FE02:6EA5 same as 2001::260:97FF:FE02:6EA5 IPv6 Unicast Addresses 64 bits for Subnet + 64 bits for Interface ID Prefix + Subnet ID + Interface ID = IPv6 128 bit Address Prefix is the Global Routing Prefix (48 bits) Subnet ID is the subnet identifier within a site (16 bits) Interface ID is the interface identifier for a particular host or other device (64 bits) Represented in 16 bit Hexadecimal Number From ONE: To ONE: SOURCE -----------------------------Unicast Destination Routing Prefix Like the Network ID in IPv4 48 bits 1st three bits are fixed at “001” for unicast Next 45 bits - Regional Internet Registries determine how these bits are allocated. These bits are typically a combination of Level Identifier fields. For example, you could have: Level 1 Identifer (10 bits) for largest organizations + Level 2 Identifer (12 bits) for lower level organizations + Level 3 Identifer (23 bits) for Level 2’s customers Who’s in charge? IANA – Internet Assigned Numbers Authority is in charge of all IP address assignment and internet parameters. (owned and ran by ICANN) ICANN – Internet Corporation for Assigned Names and Numbers is a private, non-profit company responsible for all registration tasks such as IP address assignment, domain name assignment, and protocol parameters management. (ICANN has allowed accredited registrars to register names in many of the top-level domains) Often referred to as: IANA/ICANN or ICANN/IANA Back to IPv6 Addresses… How do they do it? IANA assigns largest blocks of addresses to RIRs (Regional Internet Registries) What’s an RIR? An RIR is a Regional Internet Registry that is responsible for managing IP addresses and Autonomous System numbers for a particular region. So who are the RIRs? APNIC – Asia Pacific Network Information Centre responsible for Asia/Pacific region ARIN – American Registry for Internet Numbers responsible for North America, part of the Carribean LACNIC – Latin American and Carribean Internet Addresses Registry responsible for Latin America and part of the Carribean RIPE-NCC – Réseaux IP Européens Network Coordination Center responsible for Europe, Middle East, and Central Asia AfriNIC - African Internet Numbers Registry responsible for continental Africa and the Indian Ocean IPv6 Multicast Addresses 1st 8 bits are all 1’s i.e., 1111 1111; Translate into Hex: FF Indicator (8 bits) + Flags (4 bits) + Scope ID (4 bits) + Group ID (112 bits) = IPv6 128 bit Multicast Address Indicator – 1st eight bits set to 1’s signifying a multicast packet. Flags – 1st three are 0’s. The last is either a “0” for a permanent/well known multicast address or a “1” for a transient multicast address. Scopes – Globally across the Internet or Locally within the organization Group – Defines a particular group within a scope. From ONE: SOURCE To MANY: ----------------------------- Multicast Destinations ----------------------------- Multicast Destinations ----------------------------- Multicast Destinations Multicast Scopes Node-Local (within a node) Link-Local (within a local network) Site-Local (within a local site) OrganizationLocal (within an organization) Global (across the Internet) Note: As the Scope ID Value Increases, the Scope expands to cover larger areas. Well Known Multicast Addresses FF01:0:0:0:0:0:1 used to multicast to all nodes for node-local. (Notice: FF signifies multicast, scope id of 1 signifies node-local, and group id of 1 signifies all nodes) FF02:0:0:0:0:0:1 used to multicast to all nodes for link-local. (Notice: FF signifies multicast, scope id of 2 signifies link-local, and group id of 1 signifies all nodes) Multicasting to “all nodes” replaces IPv4 Broadcasts. More well-known Multicast Addresses FF01:0:0:0:0:0:2 used to multicast to all routers for node-local. (Notice: FF signifies multicast, scope id of 1 signifies node-local, and group id of 2 signifies all routers) FF02:0:0:0:0:0:2 used to multicast to all routers for link-local. (Notice: FF signifies multicast, scope id of 2 signifies link-local, and group id of 2 signifies all routers) FF05:0:0:0:0:0:2 used to multicast to all routers for node-local. (Notice: FF signifies multicast, scope id of 5 signifies site-local, and group id of 2 signifies all routers) IPv6 Anycast Addresses Anycast Packets are new to IPv6 Automatically sends packet to the closest member within a group. Provides flexibility when requesting a service provided by several different routers. Designed for devices within the same network. Addresses assigned from Unicast Addressing space. Subnet Prefix (# bits) + Interface Identifier (128 - # bits in Subnet Prefix) = IPv6 128 bit Anycast Address Interface Identifier is set to ALL 0’s. Subnet-Router Anycast Address is required to communicate with one of multiple routers in a particular subnet. From ONE: SOURCE ----------------------------------------------------------------------------------------- To ONE of Many: Multicast Destination Multicast Destination CLOSEST Multicast Destination Deploying IPv6 Migration to IPv6 from IPv4 will not occur all at once…it’s way too complex IPv4 and IPv6 must coexist Migration requires careful planning Overall transition worldwide will take several years Migrating from IPv4 to IPv6 Methods that make the migration easier. Dual-Stack – running both IPv4 and IPv6 simultaneously. Applications talk to both. Tunneling – wrapping or packaging one type of packet into another to be sent on dissimilar network i.e., tunneling ipV6 packets on IPv4 network Translation – converting IPv4 to IPv6 and vice versa which can be complex and result in problems. Required for devices that only support one version. (temporary solution until more devices make the move to IPv6) IPv6/IPv4 Address Embedding – embeds the IPv4 addresses within the IPv6 address structure Dual-Stack Devices are IPv6 Aware Devices speak both IPv6 and IPv4 Dual Stack is the primary approach for introducing IPv6 into an IPv4 network Tunneling Enables interconnection of IP networks. IPv6 networks can be connected through an IPv4 WAN link. IPv6 packets are encapsulated and decapsulated by border routers for transmission over the IPv4 WAN link. Thus, IPv6 packets are tunnelled through the IPv4 network cloud. Translation Required when IPv6 host needs to communicate with IPv4 host. Application Level Gateways (ALGs) are required to translate. Can be implemented in border routers and hosts. Temporary Solution Complexity and overhead issues IPv6/IPv4 Address Embedding Addresses are in the Reserved Block for IPv6 addresses. The first 80 bits are zeroes. (Recall that the reserved block has zeroes in the first 8 bits) IPv4 addresses are put in special format IPv6 address so they are recognized as IPv4 addresses by IPv6 devices. Types of Embedding IPv4-Compatible IPv6 Addresses Used with IPv6 capable devices All zeroes for middle 16 bits 80 zeroes + 16 zeroes + 32 bit IPv4 Address Example in Hybrid IPv4-Compatible format: ::220.127.116.11 Example in Standard IPv6 Hexadecimal format: ::4457:4882 IPv4-Mapped IPv6 Addresses Regular IPv4 addresses that have been mapped into IPv6 addresses Used with devices that are only IPv4 capable All ones for middle 16 bits 80 zeroes + 16 ones + 32 bit IPv4 Address Example in Hybrid IPv4-Compatible Format: ::FFFF:18.104.22.168 Example in Standard IPv6 Hexadecimal format: ::FFFF:4457:4882 IPv6 Post Check Now, go back to your IPv6 Pre/Post Concept Check paper with your Key Terms Rate your understanding of the Key Terms on the Right Side. Remember: (+) = Expert (√ ) = Heard of it (-) = Have not heard of it Reflection as a group. Summary IPv6 or Internet Protocol Version 6 is the successor to IPv4 or Internet Protocol Version 4. It is needed to address the need for additional address space with an ever growing Internet population as well as new internet devices. IPv6 addresses are written in Colon Hex notation. IPv6 addresses are Unicast, Multicast, and Anycast. Broadcast is not part of IPv6. IPv6 has four special addresses: Reserved, Private, Loopback, and Unspecified. Two colons in an address represent successive leading zeroes. Summary #2 IANA assigns blocks of addresses to RIRs. RIRs manage addresses for a particular region. Full IPv6 deployment will take years. IPv4 and IPv6 must coexist in the meantime. Dual-Stack, Tunneling, Translation, and IPv6/IPv4 Address Embedding all make the migration easier.