《IPv6技術(shù)講座》PPT課件.ppt
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1、2021/2/21 1 IPv6技術(shù)講座 滕小玲 北京大學(xué)計(jì)算中心 2021/2/21 2 主要內(nèi)容 為什么使用 IPv6 IPv6主要特性 IPv6報(bào)頭 IPv6地址 IPv6的發(fā)展歷程 2021/2/21 3 為什么使用 IPv6 The Case for IPv6 IPv4所面臨的問題 IPv4的地址嚴(yán)重匱乏 路由表急劇膨脹 網(wǎng)絡(luò)安全 暫時(shí)的解決方法 NAT CIDR 2021/2/21 4 IPv6主要特性 Larger Address Space 128位 Aggregation-based address hierarchy Efficient backbone routing
2、Efficient and Extensible IP datagram No fragmentation by routers 64 bits field alignement Simpler basic header Autoconfiguration Security IP Renumbering part of the protocol 2021/2/21 5 IPv6報(bào)頭 IPv 6 Pa c k e t De sc rip ti o n RF C2 460 V e r T r af f ic C l as s F l o w L ab e l P ayl oad L e n gt
3、h N e x t H e ad e r Hop L im it 128- b it S ou r c e A d d r e s s 128- b it D e s t in at ion A d d r e s s 2021/2/21 6 IPv6報(bào)頭 Version(4bits) 6 for IPv6 Traffic Class(8 bits) TOS in IPv4 identify classes and priorities(diffserv) Flow Label(20 bits) PayloadLength( 16 bits) Next Header(8bits) Extens
4、ible header structure Hop Limit (8 bits) TTL in IPv4 2021/2/21 7 IPv6地址類型 RFC2373 可聚集全球地址 ( Aggregateable Global Unicast Addresses) 001 1/8 total space 鏈路本地地址 ( Link-Local Unicast Addresses) 1111111010 1/1024 total space 節(jié)點(diǎn)本地地址 ( Site-Local Unicast Addresses) 1111111011 1/1024 total space 多點(diǎn)傳送地址 ( M
5、ulticast Addresses) 11111111 1/256 total space 2021/2/21 8 IPv6地址 Unicast addresses Link-Local FE80:/10 automatically configured with interface id used for neighbor and router discovery Aggregateable Global 2000:/3 T LA N LA S LA Inte rfa c e ID 1 6 b i t s 3 2 b i t s 1 6 b i t s 6 4 b i t s 2021/2
6、/21 9 IPv6地址 Multicast Addresses RFC2375 IPv6 Multicast Address Assignment FF00:/8 FFfs:/16 f: flag 0: permanent; 1: not permanent s: scope 1: node 2: link 5: site 8: organization E: global FF02:1 all nodes on the local network FF02:2 all routers on the local network 2021/2/21 10 IPv6地址 Anycast Addr
7、esses RFC2526 Reserved IPv6 Subnet Anycast Addresses Advantages of anycast routing optimization server load Anycast address style 2021/2/21 11 IPv6地址表示 Format is x:x:x:x:x:x:x:x x is a 16 bit hexadecimal field FEDC:BA98:7654:3210:FEDC:BA98:7654:3210 Leading zeros in a field are optional : can be use
8、d to represent multiple groups of 16 bits of zero : can only be used once in an address FF01:0:0:0:0:0:0:101 = FF01:101 0:0:0:0:0:0:0:1 = :1 0:0:0:0:0:0:0:0 = : 2021/2/21 12 IPv6地址表示 Loopback Addresses :1 Like 127.0.0.1 in IPv4 Automatic IPv6 Over IPv4 Tunnel : IPv4 Compatible Addresses :FFFF: for I
9、Pv4-only nodes 2021/2/21 13 IPv6地址表示 RFC2732: Preferred Format for Literal IPv6 Addresses in URL http:/1080:8:800:200C:417A:80/index.html 2021/2/21 14 IPv6地址 Required Node Addresses Its Link-Local Address for each interface Assigned Unicast Addresses Loopback Address All-Nodes Multicast Addresses So
10、licited-Node Multicast Address for each of its assigned unicast and anycast addresses Multicast Addresses of all other groups to which the host belongs. 2021/2/21 15 IPv6地址 Required Router Addresses All the required node addresses The Subnet-Router anycast addresses for the interfaces it is configur
11、ed to act as a router on. All other Anycast addresses with which the router has been configured. All-Routers Multicast Addresses 2021/2/21 16 IPv6的發(fā)展歷程 6BONE IPv6地址分配 CERNET IPv6實(shí)驗(yàn)床 北京大學(xué) IPv6實(shí)驗(yàn)床 2021/2/21 17 6BONE 國際 IPv6實(shí)驗(yàn)床,不是實(shí)用的網(wǎng)絡(luò)。 通過 tunnels 和一些純 IPv6鏈接 (mostly IPv6 over ATM) 技術(shù)文檔 RFC2471 IPv6 Te
12、sting Address Allocation 3FFE:/16 6bone TLA RFC2546 6bone routing policies 6Bone registry http:/ 2021/2/21 18 IPv6地址申請 主要分配 IPv6地址的機(jī)構(gòu): IANA( Internet Assigned Numbers Authority) 1999年 12月, IANA開始通過分配正式的 IPv6地址 200:/13 歐洲的 RIPE-NCC 亞太平洋地區(qū)的 APNIC CERNIC 地址范圍為 2001:250:/35 2021/2/21 19 CERNET IPv6 Test
13、bed 背景 1998年 6月加入 6BONE 同年 11月成為其骨干成員 1999年, CERNET在國內(nèi)教育網(wǎng)范圍內(nèi)組建了 IPv6試驗(yàn)床 目標(biāo) 研究同下一代互聯(lián)網(wǎng)有關(guān)的網(wǎng)絡(luò)技術(shù) 開發(fā)新型網(wǎng)絡(luò)應(yīng)用 示范上述技術(shù)和應(yīng)用,推動(dòng)國內(nèi) IPv4向 IPv6的過度 2021/2/21 20 Addressing B i t 3 13 32 16 64 FP T L A I D G e n e r a l a d d r e s s a r c h i - t e c t u r e * De f i n i t i o n 001 0 x 1 F F E N L A I D S L A ID I n
14、 te r fa c e I D V a l u e 3F F E : 32 x r : p oo o: aa aa : aa aa : aa aa : aa a a: aa aa M e a n i n g TLA F o r 6b o n e p s eu d o - T L A I D F o r C E R N E T R egi o n N L A 1 ID O rg an i z at i o n N L A 2 ID S u b n et ID N et w o rk I n t er f ace I D Ad d r e s s a r c h i - t e c t u r
15、e i n t h e T e s t b e d B i t 16 8 8 16 16 64 N ot e s : On ly g lob al aggregateable unicast address architectu re is descri bed. FP : F o r m a t P r e f i x; 00 1 = a gg r e ga t a bl e g l o ba l u ni c a s t a dd r e s s e s TLA : T o p L e v e l A gg r e ga t i o n; 0 x 1FF E = 6b o n e N L
16、A : N e x t L e ve l A gg r e ga t i o n SL A : S i t e L e v e l A gg r e ga t i o n x : 0 = Of f ic ia l; 1 = St ud e nt E x pe r im e nt r : R e gion C ode ( s pe c if ie d by C E R N E T ) p : C ode f or P r ov in c e ( s pe c if ie d by N L A 1 de l e ga t ion in t he r e gion) ooo : Or ga ni z
17、 at ion C ode ( s pe c if ie d by N L A 1 de l e ga t ion in t he r e gion) 2021/2/21 21 Addressing p TL A: CE RN ET N LA1 : P r o vi n c e C od e p =r R e g i o n 1 2 3 4 5 1 No r t h C h i n a B e ij i n g T ia n j i n H e b e i S h a n xi I n n e r M on g o li a 2 No r t h Wes t S h aa n xi G a n
18、 s u Ni n g x ia Q i n g h ai Xi n j i a n g 3 S ou t h Wes t S ic h u a n C h on g q i n g G u i z h ou Y u n n a n T ib e t 4 S ou t h C h i n a G u a n gd on g G u a n g x i H ai n a n 5 Ce n t r al C h i n a H u b e i H u n a n H e n a n 6 E as t Ch i n a N Jia n gs u A n h u i S h a n d on g 7
19、E as t Ch i n a S S h a n g h ai Z h e j ia n g Jia n g xi F u j ia n 8 No r t h E as t L iaon i n g Jil i n H e il on g j ia n g 2021/2/21 22 CERNET IPv6 Testbed Contact Information: Technical Staff General Mail List URL http:/ 2021/2/21 23 加入實(shí)驗(yàn)床 遵從如下的程序 加入試驗(yàn)床的郵件列表 M 組建 IPv6網(wǎng)絡(luò) 規(guī)劃網(wǎng)絡(luò)地址和拓?fù)?申請地址空間和接入
20、點(diǎn) 配置主機(jī)和路由節(jié)點(diǎn) 申請域名 2021/2/21 24 北京大學(xué) IPv6實(shí)驗(yàn)床 2000年 4月開始 Nokia路由器和 FreeBSD系統(tǒng) IPv6 over IPv4 測試路由和 DNS 移植 tcp_wrappers 2021/2/21 25 IPv6實(shí)驗(yàn)床結(jié)構(gòu) 2021/2/21 26 IPv4到 IPv6網(wǎng)絡(luò)應(yīng)用的遷移 SUN Scrubber IPv6 Socket API RFC2133,RFC2292,RFC2553 已有的 IPv6網(wǎng)絡(luò)應(yīng)用: BIND SENDMAIL APACHE TCPDUMP NEWS 2021/2/21 27 相關(guān)站點(diǎn)資源 http:/www.
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