* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download IPv6
Survey
Document related concepts
Computer network wikipedia , lookup
Asynchronous Transfer Mode wikipedia , lookup
Point-to-Point Protocol over Ethernet wikipedia , lookup
Internet protocol suite wikipedia , lookup
SIP extensions for the IP Multimedia Subsystem wikipedia , lookup
Multiprotocol Label Switching wikipedia , lookup
IEEE 802.1aq wikipedia , lookup
Wake-on-LAN wikipedia , lookup
Deep packet inspection wikipedia , lookup
Dynamic Host Configuration Protocol wikipedia , lookup
Recursive InterNetwork Architecture (RINA) wikipedia , lookup
Transcript
IPv6 Sirak Kaewjamnong Computer Networks Agenda • • • • • • IPv4’s limitations? Protocol Features Addressing IPv4 V.S. IPv6 functional comparison IPv6 Standards Conclusion 2 IPv4’s Limitations • • Two driving factors : addressing and routing Addressing : address depletion concerns – Internet exhaust the IPv4 address space between 2005 and 2011 [RFC1752]. • Routing : routing table explosion – Currently ~120K entries in core router • More factors... – Opportunity to optimized on many years of deployment experience – New features needed : multimedia, security, mobile, etc.. 3 Key Issues The new protocol MUST • Support large global internetworks • A clear way to transition IPv4 based networks 4 What is IPv6? • IPv6 is short for "Internet Protocol Version 6". • IPv6 is the "next generation" protocol designed by the IETF to replace the current version Internet Protocol, IP Version 4 5 History of the IPv6 Effort (1) • 1990 : IETF defined a new version of IP, generally called IP Next Generation or IPng • Spring 1992 : IAB proposed the OSI CLNP (Connectionless Network Protocol). Finally rejected by IETF and working groups • Feb 1992: 4 proposals for IPng – CNAT, IP Encaps, Nimrod, Simple CLNP 6 History of the IPv6 Effort (2) • March 1992: merging – IP Encaps to IPAE (IP Address Encapsulation) – Simple CLNP to TUBA (TCP and UDP with bigger Address) • Dec 1992: 3 more proposals for IPng – PIP (P Internet Protocol), SIP (Simple IP), and TP/IX • Fall 1993 : resolution to 3 possibilities : – TUBA – TP/IX => CATNIP (Common Architecture for the Next Generation Internet Protocol) – SIP+IP encaps+PIP=> SIPP (Simple Internet Protocol Plus) • Jul 1994 : SIPP was chosen, known as IPv6 7 IPV6 Key Advantages • • • • • • • 128 bit fix length IP address Real time support Self-configuration of workstations or auto configuration Security features Support mobile workstations Protocol remains the same principle IPv4 compatibility 8 IPV6 Address Representation • Hexadecimal values of the eight 16-bit pieces x:x:x:x:x:x:x:x Example FEDC:BA98:7654:3210:FEDC:BA98:7654:3210 1080:0:0:0:8:800:200C:417A Compressed form: "::" indicates multiple groups of 16-bits of zeros. 1080:0:0:0:8:800:200C:417A FF01:0:0:0:0:0:0:101 0:0:0:0:0:0:0:1 0:0:0:0:0:0:0:0 1080::8:800:200C:417A FF01::101 ::1 :: 9 IPV6 Address Representation(cont) • Mixed environment of IPv4 and IPv6 address IPv4-compatible IPv6 address technique for hosts and routers to dynamically tunnel IPv6 packets over IPv4 routing infrastructure 0:0:0:0:0:0:13.1.68.3 => :: 13.1.68.3 IPv4-mapped IPv6 address represent the addresses of IPv4-only nodes (those that do not support IPv6) as IPv6 addresses IPv4-only IPv6-compatible addresses are sometimes used/shown for sockets created by an IPv6-enabled daemon, but only binding to an IPv4 address. These addresses are defined with a special prefix of length 96 (a.b.c.d is the IPv4 address): 0:0:0:0:0:FFFF:129.144.52.38/96 => :: FFFF:129.144.52.38/96 10 http://www.tldp.org/HOWTO/Linux+IPv6-HOWTO/x324.html Format Prefix • Format Prefix : – Leading bits indicate specific type of an IPv6 address – The variable-length field – Represented by the notation: IPv6-address/prefix-length Example : the 60-bit prefix 12AB00000000CD3 12AB:0000:0000:CD30:0000:0000:0000:0000/60 12AB::CD30:0:0:0:0/60 12AB:0:0:CD30::/60 11 Type of Addresses Three type of addresses UNICAST : defines a single interface A packet sent to a unicast address is delivered to the interface identified by that address. • ANYCAST : defines a set of interfaces A packet sent to an anycast address is delivered to one of the interfaces • MULTICAST : defines a set of interfaces A packet sent to a multicast address is delivered to all interfaces identified by that address • 12 Address Types • Unspecified address, 0:0:0:0:0:0:0:0 or :: • Loopback address, 0:0:0:0:0:0:0:1 of ::1 • Global address, 2000::/3 and E000::/3 currently only 2000::/3 is being assigned • Link local address, FE80::/64 • Site local address, FEC0::/10 13 IPV6 Address Allocation Allocation Prefix bit Prefix form at fraction of address apace Reserved 0000 0000 0::/8 1/256 Unassigned 0000 0001 100::/8 1/256 Reserved for NSAP Allocation Reserved for IPX Allocation 0000 001 0000 010 200::/7 400::/7 1/128 1/128 Unassigned 0000 011 600::/7 1/128 Unassigned 0000 1 800::/5 1/32 Unassigned 0001 1000::4 1/16 Aggregatable Global Unicast Addresses 001 2000::/3 1/8 Unassigned 010 4000::/3 1/8 Unassigned 011 6000::/3 1/8 Unassigned 100 8000::/3 1/8 Unassigned 101 A000::/3 1/8 Unassigned 110 C000::/3 1/8 Unassigned 1110 E000::/4 1/16 Unassigned 1111 0 F000::/5 1/32 Unassigned 1111 10 F800::/6 1/64 Unassigned 1111 110 FC00::/7 1/128 Unassigned 1111 1110 0 FE00::/9 1/512 Link-Local Unicast Addresses Site-Local Unicast Addresses Multicast Addresses 1111 1110 10 1111 1110 11 1111 1111 FE80::/10 FEC0::/10 FF00::/8 1/1024 1/1024 1/256 14 Address Registries Address registries for IPv6 are the same one as for IPv4, ARIN,RIPE and APNIC. • Only large network providers will ever obtain addresses directly from the registries, such as UNINET : one such provider in Thailand • If a /35 prefix is allocates, the registry internally will reserve a /32. • The basic unit of assignment to any organization is a /48 prefix 15 Aggregatable Unicast Address Three level hierarchy: • Public Topology : providers and exchanges who provide public Internet transit services (P1, P2, P3, P4, X1, X2, P5 and P6) P3 P1 x2 X1 P2 P4 • Site Topology : does not provide public transit service to nodes outside of the site (S1, S2, S3, S4, S5 and S6) S1 S2 P5 S4 • S5 P6 S3 S6 Interface Identifier: interfaces on links 16 Aggregatable Unicast Address 3 13 8 FP TLA ID RES 24 NLA ID Public Topology FP=Format Prefix= 001 TLA= Top Level Aggregation RES= Reserved NLA=Next-Level Aggregation SLA=Site-Level Aggregation 16 SLA ID 64 bits Interface ID Site Topology Interface Identifier 17 Header Comparison 0 15 16 vers hlen 20 bytes TOS • flags protocol frag offset header checksum source address destination address • options and padding pay load length 40 bytes flow label next header hop limit • source address Added: (2) – Traffic class – flow label destination address IPv6 Changed: (3) – total length=> payload – protocol => next header – TTL=> hop limit IPv4 vers traffic class Removed (6) – ID, Flags, frag offset – TOS, hlen – header checksum total length identification TTL 31 • Expanded – address 32 bits to 128 bits 18 IPv6 Node Configuration • Ethernet address is an IEEE EUI-48 • Node address is an IEEE EUI-64 • EUI-48 can be converted into an EUI-64 by inserting the bits FF FE between the 3 rd and 4th octets EUI-48 EUI-64 00:06:5B:DA:45:AD = 00:06:5B:FF:FE:DA:45:AD 19 Auto configuration “Plug and play” feature • Stateless mode :via ICMP (no server required) Prefix 4c00::/80 Link Address 00:A0:C9:1E:A5:B6 IPv6 Address 4c00::A0:C9FF:EF1E:A5B6 Router adv. • Stateful server mode : via DHCP 00:A0:C9:1E:A5:B6 DHCP server DHCP request DHCP response 4c00::A0:C9FF:FE1E:A5B6 20 Multimedia Support • Applications reserve resources in advance via Flow Label Workstation Flow1 File Server Flow2 Multimedia Server PC All packets belonging to the same flow must be sent with the same source/destination address, priority, and flow label 21 Security • • Authentication/Confidential Authentication: – MD5 based • Confidential : – payload encryption – Cipher Block Chaining mode of the Data Encryption Standard (DES-CBC) 22 Support Protocols • • • • ICMPv6 [RFC1885] DHCPv6 DNS extensions to support IPv6 [RFC1886] Routing Protocols – – – – – RIPv6 [RFC2080] OSPFv6 IDRP IS-IS Cisco EIGRP 23 Transition Strategy • • • Dual Stack – run both IPv4 and IPv6 Tunneling – IPv6 packet over IPv4 infrastructure Header Translation – IPv4-only by header translation 24 Dual Stack • • Dual stack hosts support both IPv4 and IPv6 Determine stack via DNS Application TCP IPv6 IPv4 Ethernet IPV6 Dual stack host IPv4 25 Tunneling: automatic tunneling • • Encapsulate IPv6 packet in IPv4 Rely on IPv4-compatible IPv6 address IPv6 host ::1.2.3.4 R1 IPv4 Network 2.3.4.5 ::2.3.4.5 6 traffic flow label payload len next hops src = ::1.2.3.4 (IPv4-compatible IPv6 adr) dst = ::2.3.4.5 (IPv4-compatible IPv6 adr) payload IPv4/6 host 2.3.4.5 R2 2.3.4.5 4 hl TOS len frag id frag ofs TTL prot checksum src: 1.2.3.4 dst: 2.3.4.5 6 traffic flow label 4 hl TOS len frag id frag ofs TTL prot checksum src: 1.2.3.4 dst: 2.3.4.5 6 traffic flow label payload len payload len next hops next hops src = ::1.2.3.4 (IPv4-compatible IPv6 adr) src = ::1.2.3.4 (IPv4-compatible IPv6 adr) dst = ::2.3.4.5 (IPv4-compatible IPv6 adr) dest = ::2.3.4.5 (IPv4-compatible IPv6 adr) payload payload 26 Tunneling : configured tunneling • • Encapsulate IPv6 packet in IPv4 Rely on IPv6-only address IPv6 address (IPv4-compatible address are unavailable) IPv6 host ::1:2:3:4 R1 ::2:3:4:5 6 traffic flow label payload len next src = ::1:2:3:4 (IPv6 adr) dst = ::2:3:4:5 (IPv6 adr) payload hops IPv6 host :: 2:3:4:5 IPv4 Network R2 ::2:3:4:5 R2 4 hl TOS len frag id frag ofs TTL prot checksum src = R1 dst =R2 6 traffic flow label payload len next src =::1:2:3:4 (IPv6 adr) hops 6 traffic flow label payload len next hops src = ::1:2:3:4 (IPv6 adr) dst = ::2:3:4:5 (IPv6 adr) payload dst = ::2:3:4:5 (IPv6 adr) payload 27 Header Translation Full IPv6 system need to support few IPv4-only systems rely on IPv6 host IPv4-mapped ::1:2:3:4 IPv6 address R1 ::2:3:4:5 IPv4 host 2.3.4.5 IPv6 Network R2 2.3.4.5 ::2.3.4.5 6 traffic flow label 6 traffic flow label payload len next payload len next src = ::1:2:3:4 (IPv6 adr) dst = ::2.3.4.5 (IPv6 adr) payload hops src = ::1:2:3:4 (IPv6 adr) dst = ::2.3.4.5 (IPv6 adr) hops 4 hl TOS len frag id frag ofs TTL prot checksum src = R1 dst =R2 payload payload 28 Migration Steps 1. Upgrade DNS servers to handle IPv6 Address 2. Introduce dual stack systems that support IPv4 and IPv6 3. Rely on tunnels to connect IPv6 networks separated by IPv4 networks 4. Remove support for IPv4 5. Rely on header translation for IPv4-only systems 29 Conclusion • • IPv6 will provide for future Internet growth and enhancement IPv6 : – – – – – solve the Internet scaling problem support large hierarchical address provide a flexible transition mechanism interoperate with IPv4 provide a platform for new Internet functionality 30