IPv4/IPv6 协议 清华大学研究生课程

Transcription

1 IPv4/IPv6 协议 1 清华大学研究生课程

2 << 上一页 2 下一页 >> Outline Protocol Background Technology Highlights Enhanced Capabilities Transition Issues Next Steps

3 << 上一页 3 下一页 >> What Ever Happened to IPv5? 0 IP March 1977 version (deprecated) 1 IP January 1978 version (deprecated) 2 IP February 1978 version A (deprecated) 3 IP February 1978 version B (deprecated) 4 IPv4 September 1981 version (current widespread) 5 ST Stream Transport (not a new IP, little use) 6 IPv6 December 1998 version (formerly SIP, SIPP) 7 CATNIP IPng evaluation (formerly TP/IX; deprecated) 8 Pip IPng evaluation (deprecated) 9 TUBA IPng evaluation (deprecated)

4 IPv4 header structure Version Version IHL IHL Time-to-live Time-to-live Identification Identification Type Type of of Service Service Protocol Protocol Options Options Total Total length length of of IP IP datagram datagram Flags Flags Fragment Fragment offset offset Header Header checksum checksum (for (for error error control) control) Source Source IP IP address address Destination Destination IP IP address address Padding Padding Payload Payload of of IP IP datagram datagram Version (4 bits): tells that this is IP Version 4 (IPv4) << 上一页 4 下一页 >>

5 << 上一页 5 下一页 >> IPv4 header structure Version Version Time-to-live Time-to-live IHL IHL Type Type of of Service Service Identification Identification Protocol Protocol Options Options Total Total length length of of IP IP datagram datagram Flags Flags Fragment Fragment offset offset Header Header checksum checksum (for (for error error control) control) Source Source IP IP address address Destination Destination IP IP address address Padding Padding Payload Payload of of IP IP datagram datagram Header length (4 bits) is needed since Options + Padding can vary in length. Options:Security (packet classification), Strict source routing (the whole routing list), Loose source routing (the mandatory routing list), Record route (record the IP address of each hop), Timestamp (record the IP address and timestamp of each hop).

6 IPv4 header structure Version Version IHL IHL Time-to-live Time-to-live Identification Identification Type Type of of Service Service Protocol Protocol Options Options Total Total length length of of IP IP datagram datagram Flags Flags Fragment Fragment offset offset Header Header checksum checksum (for (for error error control) control) Source Source IP IP address address Destination Destination IP IP address address Padding Padding << 上一页 6 下一页 >> Payload Payload of of IP IP datagram datagram ToS = Type of Service (8 bits) is used for QoS management purposes. The first 3 bits of TOS indicate priorities, 0 being low (normal packet) and 7 being high (network control packet); the next 3 bits indicate service types, being delay, throughput, and reliability; the last 2 bits are reserved. Source could use service type bits to indicate the routing metrics to be used.

7 IPv4 header structure Version Version IHL IHL Time-to-live Time-to-live Identification Identification Type Type of of Service Service Protocol Protocol Options Options Total Total length length of of IP IP datagram datagram Flags Flags Fragment Fragment offset offset Header Header checksum checksum (for (for error error control) control) Source Source IP IP address address Destination Destination IP IP address address Padding Padding Payload Payload of of IP IP datagram datagram Datagram length (16 bits): since this field is 16 bits long, the IP datagram can contain up to 2 16 = bytes (in theory). Most routers, however, cannot handle such large datagrams. << 上一页 7 下一页 >>

8 << 上一页 8 下一页 >> IPv4 header structure Version Version IHL IHL Time-to-live Time-to-live Identification Identification Type Type of of Service Service Protocol Protocol Flags Flags All fragments Has value contain the same zero in last Options number Optionsfragment Payload Payload of of IP IP datagram datagram Total Total length length of of IP IP datagram datagram Fragment Fragment offset offset Header Header checksum checksum (for (for error error control) control) Source Source IP IP address address Position Destination of fragment Destination IP IP address address in original datagram Padding Padding IP fragmentation: a large IP datagram may be fragmented (in any router along the path) and will be reassembled at the destination. Flags: 1st bit reserved; 2nd bit DF, 0=fragment yes, 1= fragment no; 3rd bit MF, 0=last fragment, 1=more fragment.

9 IPv4 header structure Version Version IHL IHL Time-to-live Time-to-live Identification Identification Type Type of of Service Service Protocol Protocol Options Options Flags Flags Total Total length length of of IP IP datagram datagram Fragment Fragment offset offset Header Header checksum checksum (for (for error error control) control) Source Source IP IP address address Destination Destination IP IP address address Padding Padding Payload Payload of of IP IP datagram datagram Time-to-live (8 bits): this number is decreased by one in each router along the path. If number zero is reached in a router, IP datagram is discarded and router sends an ICMP message (TTL expired) to the source of the datagram. << 上一页 9 下一页 >>

10 IPv4 header structure Version Version IHL IHL Time-to-live Time-to-live Identification Identification Starts here... Type Type of of Service Service Protocol Protocol Options Options Flags Flags Payload Payload of of IP IP datagram datagram Total Total length length of of IP IP datagram datagram Fragment Fragment offset offset Header Header checksum checksum (for (for error error control) control) Source Source IP IP address address Destination Destination IP IP address address Padding Padding Protocol field (8 bits): describes which higher layer protocol is used (TCP, UDP, SCTP...). The header of this upper protocol is located at the beginning of the IP datagram payload. e.g. 6=TCP, 17=UDP, 1=ICMP, 89=OSPF, etc. << 上一页 10 下一页 >>

11 IPv4 header structure Version Version IHL IHL Time-to-live Time-to-live Identification Identification Type Type of of Service Service Protocol Protocol Options Options Flags Flags Total Total length length of of IP IP datagram datagram Fragment Fragment offset offset Header Header checksum checksum Source Source IP IP address address Destination Destination IP IP address address Padding Padding Payload Payload of of IP IP datagram datagram Header checksum (16 bits): used for error control (if used, routers along the path have to recalculate the checksum). This kind of error control is not used in IPv6 (since the same error control function is offered by TCP - and even UDP). << 上一页 11 下一页 >>

12 IPv4 header structure Version Version IHL IHL Time-to-live Time-to-live Identification Identification Type Type of of Service Service Protocol Protocol Options Options Flags Flags Total Total length length of of IP IP datagram datagram Fragment Fragment offset offset Header Header checksum checksum (for (for error error control) control) Source Source IP IP address address Destination Destination IP IP address address Padding Padding Payload Payload of of IP IP datagram datagram Source and destination IP address (32 bits each): note that these addresses are not changed in routers along the route. << 上一页 12 下一页 >>

13 << 上一页 13 下一页 >> IPv4 协议存在的不足 地址数量不足 性能 安全性 地址自动配置

14 << 上一页 14 下一页 >> Technologies & efforts to slow the consumption rate Dial-access / PPP / DHCP Provides temporary allocation aligned with actual endpoint use Strict allocation policies Reduced allocation rates by policy of currentneed vs. previous policy based on projectedmaximum-size CIDR Aligns routing table size with needs-based address allocation policy. Additional enforced aggregation actually lowered routing table growth rate to linear for a few years NAT Hides many nodes behind limited set of public addresses

15 新一代互联网的定义和主要特征 目前还没有统一的严格定义, 新一代互联网将是一个渐进的发展过程 目前已取得共识的主要特征 更大 :IPv6 的地址空间, 网络的规模更大, 接入网络的终端种类和数量更多, 网络应用更广泛 更快 :100Mbps 以上的端到端高性能通信 更安全可信 : 对象识别, 身份认证和访问授权, 数据加密和完整性, 基于真实 IPv6 源地址的可信任网络 更及时 : 组播服务, 服务质量 (QoS), 大规模实时交互应用 更方便 : 基于移动和无线通信的丰富应用 更可管理 : 有序的管理 有效的运营 及时的维护 更有效 : 有盈利模型, 获得重大社会效益和经济效益 << 上一页 15 下一页 >>

16 << 上一页 16 下一页 >> Would increased use of NATs be adequate? NO! NAT enforces a client-server application model where the server has topological constraints They won t work for peer-to-peer or devices that are called by others (e.g., IP phones) They inhibit deployment of new applications and services, because all NATs in the path have to be upgraded BEFORE the application can be deployed

17 << 上一页 17 下一页 >> Return to an End-to-End Architecture New Technologies/Applications for Home Users Always-on Cable, DSL, Wireless, Always-on Devices Need an Address When You Call Them Global Addressing Realm

18 << 上一页 18 下一页 >> Why is a larger address space needed? Overall Internet is still growing its user base ~320 million users in 2000 ~550 million users by 2006 ~1055 million users in 2010

19 << 上一页 19 下一页 >> Why is a larger address space needed? Users expanding their connected device count 405 million mobile phones in 2000, over 3.3 billion by 2007 ~1 billion cars in % likely to use GPS and locality based Yellow Page services Billions of new Internet appliances for Home users

20 << 上一页 20 下一页 >> 128 Bits as the IPv6 Address Size Settled on fixed-length, 128- bit addresses (340,282,366,920,938,463,463, 374,607,431,768,211,456 in all!)

21 << 上一页 21 下一页 >> Benefits of 128 bit Addresses Room for many levels of structured hierarchy and routing aggregation Easy address auto-configuration Easier address management and delegation than IPv4 Ability to deploy end-to-end IPsec

22 << 上一页 22 下一页 >> Incidental Benefits of New Deployment Chance to eliminate some complexity in IP header improve per-hop processing Chance to upgrade functionality multicast, QoS, mobility Chance to include new features binding updates

23 << 上一页 23 下一页 >> Summary of Main IPv6 Benefits Expanded addressing capabilities Structured hierarchy to manage routing table growth Serverless autoconfiguration and reconfiguration Streamlined header format and flow identification Improved support for options / extensions

24 << 上一页 24 下一页 >> IPv6 Advanced Features Stateless Address Auto-configuration Mobility - More efficient and robust mechanisms Security - Built-in, strong IP-layer encryption and authentication Quality of Service

25 << 上一页 25 下一页 >> IPv6 Markets Home Networking Set-top Residential Voice over IP gateway Gaming (10B$ market) Sony, Sega, Nintendo, Microsoft Mobile devices Consumer PC Consumer Devices Sony (Mar/01 - energetically introducing IPv6 technology into hardware products ) Enterprise PC Service Providers Regional ISP, Carriers, Mobile ISP

26 << 上一页 26 下一页 >> Outline Protocol Background Technology Highlights Enhanced Capabilities Transition Issues Next Steps

27 << 上一页 27 下一页 >> The IPv6 Header 40 octets, 8 fields Version Class(8) Flow Label(20) Payload Length(16) Next Header Hop Limit 128 bit Source Address 128 bit Destination Address

28 << 上一页 28 下一页 >> Summary of Header Changes between IPv4 & IPv6 Streamlined Fragmentation fields moved out of base header IP options moved out of base header Header Checksum eliminated Header Length field eliminated Length field excludes IPv6 head

29 << 上一页 29 下一页 >> Summary of Header Changes between IPv4 & IPv6 Revised Time to Live Hop Limit Protocol Next Header Precedence & TOS Traffic Class Addresses increased 32 bits 128 bits Extended Flow Label field added

30 << 上一页 30 下一页 >> Extension Headers IPv6 header next header = TCP TCP header + data The next header refers the protocol type if no optional head IPv6 header Routing header TCP header + data next header = Routing next header = TCP IPv6 header next header = Routing Routing header next header = Fragment Fragment header next header = TCP fragment of TCP header + data

31 Extension Headers Generally processed only by node identified in IPv6 Destination Address field => much lower overhead than IPv4 options processing exception: Hop-by-Hop Options header Eliminated IPv4 s 40-byte limit on options in IPv6, limit is total packet size, or Path MTU in some cases Currently defined extension headers Hop-by-Hop Options, Routing, Fragment, Authentication, Encryption, Destination Options, Mobility << 上一页 31 下一页 >>

32 << 上一页 32 下一页 >> Fragment Header Next Header Reserved Fragment Offset 0 0 M Original Packet Identifier IPv6 frag. is an end-to-end function; routers do not fragment packets enroute if too big they send ICMP packet too big instead

33 << 上一页 33 下一页 >> Routing Same longest-prefix match routing as IPv4 CIDR Straightforward changes to existing IPv4 routing protocols to handle bigger addresses unicast: OSPFv3, RIPng, IS-IS, BGP4+, multicast: PIM, MOSPF, Use of Routing header with anycast addresses allows routing packets through particular regions e.g., for provider selection, policy, performance, etc.

34 Routing Header Next Header Hdr Ext Len Routing Type Segments Left Reserved Address[0] Address[1] << 上一页 34 下一页 >>

35 << 上一页 35 下一页 >> Example of Using the Routing Header S A B S wants to send packet to D though A and B D

36 << 上一页 36 下一页 >> Example of Using the Routing Header S A B Src Address: S Dest Address: A Routing Header Address: B and D D

37 << 上一页 37 下一页 >> Example of Using the Routing Header S A B Src Address: S Dest Address: B Routing Header Address: D D

38 << 上一页 38 下一页 >> Example of Using the Routing Header S A B Src Address: S Dest Address: D D

39 << 上一页 39 下一页 >> Some Terminology node router host link neighbors interface address a protocol module that implements IPv6 a node that forwards IPv6 packets not explicitly addressed to itself any node that is not a router a communication facility or medium over which nodes can communicate at the link layer, i.e., the layer immediately below IPv6 nodes attached to the same link a node s attachment to a link an IPv6-layer identifier for an interface or a set of interfaces

40 << 上一页 40 下一页 >> Text Representation of Addresses Preferred form: 1080:0:FF:0:8:800:200C:417A Compressed form: FF01:0:0:0:0:0:0:43 becomes FF01::43 IPv4-compatible: 0:0:0:0:0:0: or ::

41 << 上一页 41 下一页 >> IPv6 - Addressing Model Addresses are assigned to interfaces No change from IPv4 Model Interface expected to have multiple addresses Addresses have scope Link Local Site Local (FEC0::1) Global Site-Local Link-Local Global Addresses have lifetime Valid and Preferred lifetime

42 << 上一页 42 下一页 >> Types of IPv6 Addresses Unicast Address of a single interface Delivery to single interface Multicast 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 more broadcast addresses

43 << 上一页 43 下一页 >> Address Type Prefixes Address type IPv4-compatible global unicast 001 Binary prefix (96 zero bits) link-local unicast site-local unicast multicast all other prefixes reserved (approx. 7/8ths of total) anycast addresses allocated from unicast prefixes

44 << 上一页 44 下一页 >> Global Unicast Addresses 001 TLA NLA* SLA* interface ID public topology (45 bits) site topology (16 bits) interface identifier (64 bits) TLA = Top-Level Aggregator NLA* = Next-Level Aggregator(s) SLA* = Site-Level Aggregator(s)

45 << 上一页 45 下一页 >> Link-Local & Site-Local Unicast Addresses Link-local addresses for use link locallly and can t be forwarded to other links interface ID Site-local addresses for use Lan locally and can t be forwarded to the global internet SLA* interface ID

46 Interface IDs Lowest-order 64-bit field of unicast address may be assigned in several different ways: auto-configured from a 64-bit EUI-64, or expanded from a 48-bit MAC address (e.g., Ethernet address) auto-generated pseudo-random number (to address privacy concerns) assigned via DHCP manually configured possibly other methods in the future << 上一页 46 下一页 >>

47 << 上一页 47 下一页 >> Some Special-Purpose Unicast Addresses The unspecified address, used as a placeholder when no address is available: 0:0:0:0:0:0:0:0 The loopback address, for sending packets to self: 0:0:0:0:0:0:0:1

48 << 上一页 48 下一页 >> Multicast Address Format FP (8bits) Flags (4bits) Scope (4bits) RESERVED (80bits) Group ID (32bits) T Lcl/Sit/Gbl MUST be 0 Locally administered flag field low-order bit (0/1) indicates permanent/transient group (three other flags reserved) scope field: 1 - node local 8 - organization-local 2 - link-local B - community-local 5 - site-local E - global (all other values reserved)

49 << 上一页 49 下一页 >> Outline Protocol Background Technology Highlights Enhanced Capabilities Transition Issues Next Steps

50 IPv6 Security 50 清华大学研究生课程

51 << 上一页 51 下一页 >> IPv6 Security 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

52 << 上一页 52 下一页 >> Authentication Header Next Header Hdr Ext Len Reserved Security Parameters Index (SPI) Sequence Number Authentication Data Destination Address + SPI identifies security association state (key, lifetime, algorithm, etc.) Provides authentication and data integrity for all fields of IPv6 packet that do not change en-route Default algorithm is Keyed MD5

53 << 上一页 53 下一页 >> Encapsulating Security Payload (ESP) Security Parameters Index (SPI) Sequence Number Payload Padding (0/255) Padding Length Next Header Authentication Data

54 IPv6 Quality of Service 54 清华大学研究生课程

55 << 上一页 55 下一页 >> IP Quality of Service Approaches Two basic approaches developed by IETF: Integrated Service (Intserv) fine-grain (per-flow), quantitative promises (e.g., x bits per second), uses RSVP signaling Differentiated Service (Diffserv) coarse-grain (per-class), qualitative promises (e.g., higher priority), no explicit signaling

56 << 上一页 56 下一页 >> IPv6 Support for IntServ 20-bit Flow Label field to identify specific flows needing special QoS each source chooses its own Flow Label values; routers use Source Addr + Flow Label to identify distinct flows Flow Label value of 0 used when no special QoS requested (the common case today) this part of IPv6 is not standardized yet, and may well change semantics in the future, RFC3697 only gives basic specification

57 << 上一页 57 下一页 >> IPv6 Support for DiffServ 8-bit Traffic Class field to identify specific classes of packets needing special QoS same as new definition of IPv4 Type-of- Service byte may be initialized by source or by router enroute; may be rewritten by routers enroute Traffic Class value of 0 used when no special QoS requested (the common case today)

58 IPv6 Mobility 58 清华大学研究生课程

59 << 上一页 59 下一页 >> IPv4 Mobility: Vocabulary home network: permanent home of mobile (e.g., /24) home agent: entity that will perform mobility functions on behalf of mobile, when mobile is remote permanent address: address in home network, can always be used to reach mobile e.g., wide area network

60 IPv4 Mobility: more vocabulary permanent address: remains constant (e.g., ) visited network: network in which mobile currently resides (e.g., /24) care-of-address: address in visited network. (e.g., 79, ) wide area network correspondent: wants to communicate with mobile << 上一页 60 下一页 >> foreign agent: entity in visited network that performs mobility functions on behalf of mobile.

61 << 上一页 61 下一页 >> IPv4 Mobility: registration home network visited network 2 wide area network foreign agent contacts home agent : this mobile is resident in my network 1 mobile contacts foreign agent on entering visited network End result: foreign agent knows about mobile home agent knows location of mobile

62 << 上一页 62 下一页 >> IPv4 Mobility home network correspondent addresses packets using home address of mobile home agent intercepts packets, forwards to foreign agent 1 wide area network 2 foreign agent receives packets, forwards to mobile 4 3 visited network mobile replies directly to correspondent

63 << 上一页 63 下一页 >> IPv6 Mobility Mobile hosts have one or more home addresses relatively stable; associated with host name in DNS A Host will acquire a foreign address when it discovers it is in a foreign subnet (i.e., not its home subnet) uses auto-configuration to get the address registers the foreign address with a home agent, i.e, a router on its home subnet Packets sent to the mobile s home address(es) are intercepted by home agent and forwarded to the foreign address, using encapsulation

64 << 上一页 64 下一页 >> Home Agent Binding Maintenance home network visited network wide area network 1

65 << 上一页 65 下一页 >> Home Agent Binding Maintenance home network visited network wide area network 2 1

66 << 上一页 66 下一页 >> IPv6 Mobility home network home agent intercepts packets, forwards to mobile with tunnel In the inner IPv6 header, the source address is the correspondent node's address and the destination address is the mobile node's home address visited network correspondent addresses packets using home address of mobile 1 wide area network 2

67 << 上一页 67 下一页 >> IPv6 Mobility home network In the inner IPv6 header, the source address is the mobile node's home address and the destination address is the correspondent node's address. visited network 4 1 wide area network 2 3

68 ICMP and ND 68 清华大学研究生课程

69 << 上一页 69 下一页 >> ICMP Error Messages common format Type Code Checksum Parameter As much of the invoking packet as will fit without the ICMP packet exceeding MTU (code and parameter are type-specific)

70 << 上一页 70 下一页 >> ICMP Error Message Types destination unreachable no route administratively prohibited address unreachable port unreachable packet too big time exceeded parameter problem erroneous header field unrecognized next header type unrecognized option

71 << 上一页 71 下一页 >> ICMP Informational Messages Echo request & reply (same as IPv4) Multicast listener discovery messages: query, report, done (like IGMP for IPv4): Type Code Checksum Maximum Response Delay Reserved Multicast Address

72 << 上一页 72 下一页 >> Neighbor Discovery ICMP message types: router solicitation router advertisement neighbor solicitation neighbor advertisement redirect Functions performed: router discovery prefix discovery autoconfiguration of address & other parameters duplicate address detection (DAD) neighbor unreachability detection (NUD) Link-layer address resolution first-hop redirect

73 << 上一页 73 下一页 >> Router Advertisements Periodically multicast by router to allnodes multicast address (link scope) Contents: list of: prefix prefix length valid lifetime preferred lifetime on-link flag autoconfig OK flag

74 << 上一页 74 下一页 >> Other Neighbor Discovery Messages Router solicitations sent only at host start-up, to solicit immediate router advert sent to all-routers multicast address (link scope) Neighbor solicitations for address resolution: sent to solicited node multicast addr for unreachability detection: sent to neighbor s unicast addr Neighbor advertisements for address resolution: sent to unicast address of solicitor for link-layer address change: sent to all-nodes multicast addr includes router/host flag

75 << 上一页 75 下一页 >> Serverless Autoconfiguration Hosts can construct their own addresses: subnet prefix(es) learned from periodic multicast advertisements from neighboring router(s) interface IDs generated locally Other IP-layer parameters also learned from router adverts (e.g., router addresses, recommended hop limit, etc.) Higher-layer info (e.g., DNS server and NTP server addresses) discovered by multicast / anycast-based service-location protocol

76 Minimum MTU Definitions: link MTU a link s maximum transmission unit, i.e., the max IP packet size that can be transmitted over the link path MTU the minimum MTU of all the links in a path between a source and a destination Minimum link MTU for IPv6 is 1280 octets (versus 68 octets for IPv4) On links with MTU < 1280, link-specific fragmentation and reassembly must be used << 上一页 76 下一页 >>

77 << 上一页 77 下一页 >> Path MTU Discovery Implementations are expected to perform path MTU discovery to send packets bigger than 1280 octets: for each dest., start by assuming MTU of firsthop link if a packet reaches a link in which it cannot fit, will invoke ICMP packet too big message to source, reporting the link s MTU; MTU is cached by source for specific destination occasionally discard cached MTU to detect possible increase Minimal implementation can omit path MTU discovery as long as all packets kept 1280 octets e.g., in a boot ROM implementation

78 << 上一页 78 下一页 >> ND Autoconfiguration, Prefix & Parameter Discovery 1. RS 2. RA 2. RA 1. RS: ICMP Type = 133 Src = :: Dst = All-Routers multicast Address query= please send RA 2. RA: ICMP Type = 134 Src = Router Link-local Address Dst = All-nodes multicast address Data= options, prefix, lifetime, autoconfig flag Router solicitation are sent by booting nodes to request RAs for configuring the interfaces.

79 << 上一页 79 下一页 >> ND Address Resolution & Neighbor Unreachability Detection A B ICMP type = 135 (NS) Src = A Dst = Solicited-node multicast of B Data = link-layer address of A Query = what is your link address? ICMP type = 136 (NA) Src = B Dst = A Data = link-layer address of B A and B can now exchange packets on this link

80 << 上一页 80 下一页 >> ND Redirect Src = A Dst Ethernet = R1 A B R2 R1 3FFE:B00:C18:2::/64 Src = A Dst IP = 3FFE:B00:C18:2::1 Dst Ethernet = R2 (default router) Redirect: Src = R2 Dst = A Data = good router = R1 Redirect is used by a router to signal the reroute of a packet to an onlink host to a better router or to another host on the link

81 << 上一页 81 下一页 >> ND Duplicate Address Detection A B ICMP type = 135 Src = 0 (::) Dst = Solicited-node multicast of A Data = link-layer address of A Query = what is your link address? Duplicate Address Detection (DAD) uses neighbor solicitation to verify the existence of an address to be configured

82 IPv6 Routing 82 清华大学研究生课程

83 << 上一页 83 下一页 >> IPv6 Routing Straightforward changes to existing IPv4 routing protocols to handle bigger addresses RIPng Same destination/mask/metric information as RIPv2 BGP4+ MultiProtocols Extensions Integrated IS-IS 20 byte NSAP support facilitates IPv6 address/routing OSPFv3 Packet formats changed to reflect 128 bits IPv6 Multicast Routing PIM, MOSPF, MBGP have IPv6 extensions, have to move forward IPv6 Multicast has larger address space removing potential collision

84 << 上一页 84 下一页 >> BGP4+ Overview Added IPv6 address-family Added IPv6 transport All generic BGP functionality works as for IPv4

85 << 上一页 85 下一页 >> Outline Protocol Background Technology Highlights Enhanced Capabilities Transition Issues Next Steps

86 IPv4 - IPv6 Co-Existence / Transition 86 清华大学研究生课程

87 << 上一页 87 下一页 >> IPv6 Timeline (A pragmatic projection) Q Q Q 2 3 Q 4 Q Q Q 2 3 Q 4 Q Q Q 2 3 Q 4 Q Q Q 2 3 Q 4 Q Q Q 2 3 Q 4 Q Q Q 2 3 Q 4 Q Q Q 2 3 Q 4 Q Q Q 2 3 Q 4 Early adopter Application porting <= Duration 3+ years => ISP adoption <= Duration 3+ years => Consumer adoption <= Duration 5+ years => Enterprise adoption <= Duration 3+ years =>

88 DoD IPv6 Timeline Successful Transition to IPv4 from NCP in << 上一页 88 下一页 >>

89 << 上一页 89 下一页 >> Deployments IPv6 deployments will occur piecewise from the edge Core infrastructure only moving when significant customer usage demands it Whenever possible, devices and applications should be capable of both IPv4 & IPv6, to minimize the delays and potential failures inherent in translation points

90 << 上一页 90 下一页 >> Transition / Co-Existence Techniques A wide range of techniques have been identified and implemented, basically falling into three categories: (1) dual-stack techniques, to allow IPv4 and IPv6 to co-exist in the same devices and networks (2) tunneling techniques, to avoid order dependencies when upgrading hosts, routers, or regions (3) translation techniques, to allow IPv6- only devices to communicate with IPv4- only devices Expect all of these to be used, in combination

91 << 上一页 91 下一页 >> Dual-Stack Approach When adding IPv6 to a system, do not delete IPv4 Applications (or libraries) choose IP version to use This allows indefinite co-existence of IPv4 and IPv6, and gradual app-by-app upgrades to IPv6 usage

92 << 上一页 92 下一页 >> Dual-Stack and DNS Application can ask DNS server return IPv4 and IPv6 address Application can choose one of them

93 << 上一页 93 下一页 >> IPv6 Tunnel

94 Manual Configuration Tunnel << 上一页 94 下一页 >>

95 << 上一页 95 下一页 >> Translation This is a simple extension to NAT techniques, to translate header format as well as addresses IPv6 nodes behind a translator get full IPv6 functionality when talking to other IPv6 nodes located anywhere they get the normal (i.e., degraded) NAT functionality when talking to IPv4 devices

96 << 上一页 96 下一页 >> NAT-PT

97 << 上一页 97 下一页 >> Outline Protocol Background Technology Highlights Enhanced Capabilities Transition Issues Next Steps

98 << 上一页 98 下一页 >> So what can I do? Begin porting NOW! Establish test networks to verify configurations, and application compatibility

99 << 上一页 99 下一页 >> Dual Stack IPv4/IPv6 backbone

100 << 上一页 100 下一页 >> Native IPv6-Only Backbone Requires: IPv4 over IPv6 Tunnels for IPv4 traffic Hardware forwarding for IPv6 Network Management over IPv6 Not recommended today as IPv4 traffic is still the main source But it is a good testbed for IPv6 IPv4 Tunnel IPv6 Intranet IPv4 Intranet IPv6 Backbone Mobile IPv6 IPv6 Intranet IPv4/v6 Intranet Translating Gateway Translating Gateway

101 << 上一页 101 下一页 >> CERNET II

102 << 上一页 102 下一页 >>

103 << 上一页 103 下一页 >> IPv6 Myths It s more secure No except that e2e IPSEC should be possible Higher layer security must not be impacted by IP version It has better QOS No except that e2e addressing makes QOS management a bit easier It enables VoIP No but e2e addresses simplify being always on for incoming calls Big addresses solve the routing problem No routing problem is identical to IPv4 But better aggregation, simplified renumbering

104 << 上一页 104 下一页 >> IETF Hot Topics Multihoming Address allocation DNS discovery 3GPP use of IPv6 Mobile IPv6 Scoped addressing Flow labels API issues Site renumbering Address privacy DNS deployment Inter-domain multicast AAA Transition DNS development Anycast

105 << 上一页 105 下一页 >> For More Information gwg-charter.html ans-charter.html

106 << 上一页 106 下一页 >> For More Information s2000/library/howitworks/communi cations/networkbasics/ipv6.asp

107 << 上一页 107 下一页 >> 大规模 IPv6 网络新进展 全球下一代 IPv6 互联网络规模不断扩大, 主干网已经形成 Internet2,Geant2,TEIN2,CNGI 纯 IPv6 技术路线正在被逐渐采用 CNGI-CERNET2 于 2004 年开始率先采用纯 IPv6 技术 微软全球网络 2007 年 12 月全部采用纯 IPv6 技术 日本最大的下一代互联网学术网 JGN 在 2008 年开始的新一期工程中全部采用 IPv6 技术 ICANN 宣布 2010 年 IPv4 地址将分配完毕 2010 年以后新建的互联网将只能采用 IPv6 技术

108 << 上一页 108 下一页 >> IETF 的 IPv6 新进展 68 届 IETF 大会 2007 年 3 月 大会主题 : 大规模路由和寻址 解决 20 年内 100 亿 IP 地址,1000 万多接入 IP 地址的互联网路由和寻址等技术问题 69 和 70 届 IETF 大会 2007 年 7 月和 12 月 大会主题 :IPv6 解决 IPv6 大规模组网和运行管理,IPv4 向 IPv6 过渡等技术问题

109 << 上一页 109 下一页 >> 各国新的下一代互联网研究计划 美国的 FIND 和 GENI FIND:NSF 从 2005 年开始支持 GENI:NSF 从 2005 年开始策划 欧盟的 FIRE 欧盟 2007 年 7 月完成初步建议 日本 2007 年开始策划 韩国 2006 年开始策划

110 FIND:Future INternet Design 美国 NSF 的研究计划 NeTS: 传感器系统网络 NOSS 可编程的无线通信 ProWin 广义联网 NBD 未来互联网设计 FIND FIND 面向端到端的网络体系结构和设计 FIND Challenged the Research Community to: Create the Future Internet you want to have in years 30 Sep 不面向单元技术和子网 Accelerate innovations and maintain US leadership in this vital area << 上一页 110 下一页 >>

111 不断演进的 FIND 进程 30 Sep << 上一页 111 下一页 >> Iterative FIND Phases Research on architectural elements Naming, identities, forwarding, interdomain protocols, etc. Cross-cutting requirements of built-in security, robustness, manageability, economic feasibility etc. Build community and formulate architectures Multiple PI meetings, focused on aspects of architectures Inclusive of architectural researchers e.g. funded by other NSF programs, DARPA, industry, internationally funded researchers, etc. Coordinated effort to assemble overarching coherent architectures Develop small number of architectures Simulate, emulate, test on research infrastructure Explore social implications of architectures

112 FIND 计划的新进展 每年召开两次项目工作会 第四次 FIND 工作会 2007 年 11 月 日在美国华盛顿召开, 会议主要内容 特邀报告 : 进一步研讨新一代互联网需求 分四个主题研讨 : 信息层联网 灾害期间联网 高可靠性和限时传递的网络 易于管理的网络 特邀中国 日本 韩国和欧洲代表参加会议, 并探讨进行国际合作研究的可能性 << 上一页 112 下一页 >>

113 << 上一页 113 下一页 >> GENI: Global Environment for Networking Innovation 发现和评估可以作为 21 世纪互联网基础的新的革命性概念 示范和技术 建立一个支持新网络体系结构探险和评估的大规模试验环境 未来的互联网 : 值得社会信任 激发科学和工程革命 支持新技术融合 支持普适计算 成为物理世界和虚拟世界的桥梁 支持革命性服务和应用

114 << 上一页 114 下一页 >> GENI 项目的进展 2007 年初,NSF 委托 BBN 技术公司进行 GENI 工程设计, 历时四年 2009 年 4 月召开第四次 GENI 工程会议

115 << 上一页 115 下一页 >> GENI 计划时间表

116 GENI supports Fundamental Challenges in Network Science & Engineering (NetSE) Science Understand the complexity of large-scale networks - Understand emergent behaviors, local global interactions, system failures and/or degradations - Develop models that accurately predict and control network behaviors Network science and engineering researchers Technology Develop new architectures, exploiting new substrates - Develop architectures for self-evolving, robust, manageable future networks - Develop design principles for seamless mobility support - Leverage optical and wireless substrates for reliability and performance - Understand the fundamental potential and limitations of technology Distributed systems and substrate researchers Society - Design secure, survivable, persistent systems, especially when under attack - Understand technical, economic and legal design trade-offs, enable privacy protection - Explore AI-inspired and game-theoretic paradigms for resource and performance optimization Sponsored by the National Science Foundation Enable new applications and new economies, while ensuring security and privacy April 1, 2009 Security, privacy, economics, AI, social science researchers 116

117 We are here GENI Spiral 1 Multiple competing control frameworks, beginnings of an at-scale experiment plane GENI Prototyping Plan Sponsored by the National Science Foundation April 1,

118 << 上一页 118 下一页 >> 欧盟新一代互联网研究计划 The European FIRE Future Internet Research and Experimentation Activities FIRE 科学和产业预备专家组 2007 年 6 月 14 日草案

119 << 上一页 119 下一页 >> FIRE 的战略目标 FIRE is therefore an experimentally-driven long-term research initiative on Future Internet concepts, protocols and architectures, encompassing technological, industrial and socio-economic aspects. 因此,FIRE 是长期的试验驱动的原创性研究, 涉及了未来互联网的概念 协议和体系结构 相关的科技 工业和社会经济学等方面

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121 下一代互联网研究的关键技术挑战 GENI FIND FIRE 安全和鲁棒性 对网络新技术的支持 ( 特别是无线和光传输 ) 对计算新技术的支持 ( 特别是 sensor 网络 ) 新的分布式应用和系统 网络管理 良好的经济效益 相关的社会问题 << 上一页 121 下一页 >> 采用 clean-slate 的方式重新设计新一代互联网体系结构 从体系结构设计上支持安全可靠和可用 体系结构需要为信息分发 位置管理 标识管理等提供更好支持 对新技术的支持 ( 特别是无线和光传输 ) 技术和经济的相互作用 维护社会的自由和开放 移动 可扩展 安全和隐私保护

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