王忍成助理教授國立臺東大學資訊工程學系 E-mail: rcwang@nttu.edu.tw
IPv6 簡介
IPv6 第一印象 IPv4 = 32bits IPv6 = IPv6 128 bits Introduction RCWang 2011
All-IP IPv6 Introduction RCWang 2011
IPv4 的限制 因為 IPv4 address 的枯竭, 阻礙 Internet 的快速成長 IPv4 位址不斷的分割, 使得路由表日益龐 多半需要人為的設定 IP 層的安全性需求未內建 沒有 quality of service (QoS) 的支援 Limitations of IPv4 RCWang 2011
IPv4 位址不足的因應 : CIDR 廢止 IP 分類方式, 讓網路位址的位元數不在一定是 8 的倍數, 而是可變動的 加入維持路徑表大小的技術, 利用路由彙整方式來維持路由表的大小 遭遇困難 : 匯集的網路都必須是集中在附近的 各地域 國家 沿著 Network 的接續構造來分割區塊進而作分配 這跟目前實際依組織分配, 散佈全球的 IP 規劃是大不相同的, 也使得實際達成的可能性微乎其微 Limitations of IPv4 RCWang 2011
IPv4 位址不足的因應 : NAT Host 192.168.0.10 192.168.0.1 NAT Internet Server 210.240.173.16 74.125.31.103 Limitations of IPv4 RCWang 2011
NAT vs. Peer-to-Peer Applications Host A Host B NAT Internet Host C Intranet Limitations of IPv4 RCWang 2011
IPv6 的發展 1992 年 IETF 之 IPv4 的 Address 空間不足的問題開始被檢討 1994 年 下一代的網際網路協定開始被提案 1995 年 1 月,CATNIP (Common Architecture for the Internet), TUBA (TCP/IP with Bigger Addresses),SIPP (Simple Internet Protocol Plus) 三個提案中出線, 規範在 RFC1752 (The Recommendation for the IP Next Generation Protocol) 公開 12 月,SIPP 被更名為 IPv6, 第一批規範建立 RFC1883-Internet Protocol, Version 6 (IPv6) Specification RFC1884 -IP Version 6 Addressing Architecture IPv6 History RCWang 2011
IPv6 的發展 1998 年 IPv6 位址架構與通訊協定之規範修正 RFC2373 - IP Version 6 Addressing Architecture RFC2460 - Internet Protocol Version 6(IPv6) Specification 1999 年 全球第一個業界團體 ( 共有 42 個單位加盟 ) 成立了 IPv6 Forum ARIN 將全球第一個之 IPv6 Prefix: 2001:400::/35 授予給 ESnet IPv6 真正開始了 IPv6 History RCWang 2011
IPv6 History Standard RCWang 2011 IETF Standard 目前的標準規範 :1998 年 12 月 RFC2460 - Internet Protocol, Version6(IPv6) Specification Updates: 2007/12: RFC5095 - Deprecation of Type 0 Routing Headers in IPv6 2009/12: RFC5722 - Handling of Overlapping IPv6 Fragments 2010/05: RFC5871 - IANA Allocation Guidelines for the IPv6 Routing Header 2011/11: RFC6437 - IPv6 Flow Label Specification 位址的分配方式 : 2006 年 2 月 RFC4291 - Internet Protocol Version 6 (IPv6) Addressing Architecture) Updates: 2010/08: RFC5952 - A Recommendation for IPv6 Address Text Representation 2010/10: RFC6052 - IPv6 Addressing of IPv4/IPv6 Translators 裝置的需求 : 2006/04: RFC4294 - IPv6 Node Requirements 2011/04: RFC6204 - Basic Requirements for IPv6 Customer Edge Routers
IPv6 的改變 Upper Layer IP Layer Sub-IP Layer DNS DHCPv6 (RFC 3315) Transition Mechanisms Mobile IP Security Router-Specific Functionality Management Information Base Modules (MIBs) Internet Protocol Version 6 (RFC 2460) Neighbor Discovery for IPv6 (RFC 2461) Path MTU Discovery and Packet Size ICMP for the IPv6 (RFC 2463 ) Addressing Multicast Listener Discovery (MLD) for IPv6 (RFC 2710) IPv6 Packets over Ethernet (RFC2464) IPv6 over PPP(RFC2472) IPv6 over ATM (RFC2492) IPv6 Changes RCWang 2011
IPv4 與 IPv6 的差異 特性 IPv4 IPv6 位址長度 32 bits 128 bits IPSec 支援性 Optional Required QoS 支援性 Some Better 封包切割 Hosts and routers Hosts only 封包大小 576 bytes 1280 bytes 標頭驗證碼 Yes No 標頭選項 Yes No Link-layer 地址解析 ARP (broadcast) Multicast Neighbor Discovery Messages 群播群組 IGMP Multicast Listener Discovery (MLD) 路由器尋找 Optional Required 廣播功能 Yes No 設定方式 Manual, DHCP Automatic, DHCP 網域名稱查詢 Uses A records Uses AAAA records 網域名稱反向查詢 Uses IN-ADDR.ARPA Uses IP6.INT IPv4 vs. IPv6 RCWang 2011
IPv5? Internet 的版本序號是由 IANA 管理 第五版被 RFC1190(Experimental Internet Stream Protocol, Version 2(ST-Ⅱ)) 歸為實驗型行的 Protocol 新的 IP 版本就成了第六版 版本序號 :7 8 9 及 15 都已被預約了, 沒被預約的只有 10~14 因此當下一次再有 IP 的下一版本要提出時, 應該是用第十版了 IP Version RCWang 2011
IPv6 Addressing
IPv6 位址與縮寫表示法 2 32 =4,294,967,296 IPv4 = 32bits IPv6 = 128 bits 2 128 =340,282,366,920,938,463,463,374,607,431,768,211,456 IPv6 Addressing RCWang 2011
IPv6 位址與縮寫表示法 210.240.173.130 IPv4 = 32bits IPv6 = 128 bits 2001:0288:9001:0000:0000:020c:29ff:0078 2001:288:9001:0:0:20c:29ff:78 2001:288:9001::20c:29ff:78 288:9001: 0: :20c:29ff:78 0: 0 0000:000 0 00 IPv6 Addressing RCWang 2011
IPv6 Addressing RCWang 2011 Why not > 128 bits? 考慮到 IP 標頭處理所造成的浪費 協定標頭長度 M T U 標頭浪費 IPv4 20Bytes 576Bytes 3.5% IPv6 40Bytes 1,280Bytes 3.1% 位址空間擴充了, 但標頭浪費卻幾乎不變, 可以判斷這樣的位址長為 128Bits 是妥當的
IPv6 Addressing RCWang 2011 IPv6 術語 Neighbors Host Host Host Link Scope LAN segment Bridge Intra-subnet router Router Site Scope Link Global Scope Subnet Network Additional subnets
IPv6 Addressing RCWang 2011 IPv6 Prefixes 128 bits Prefix Interface ID Prefix 是位址前面固定長度的部分, 代表一個路由或子網路的識別碼 IPv6 子網路遮罩使用的是 address/prefix-length 的表示法 依循 RFC1518 CIDR 表示法 舉例說明 : 2001:288:9001::/48 for a route 2001:288:9001:117::/64 for a subnet 不再有 dotted decimal 的子網路遮罩表示法
IPv6 Addressing RCWang 2011 IPv6 位址的種類 Unicast 單一介面使用的位址 一對一連線 Multicast 一或多個介面共用的位址 一對多連線 Anycast 一或多個介面共用的位址 一對多個其中之一 ( 最接近者 ) 連線 不再有廣播位址
Unicast RCWang 2011 Unicast IPv6 Addresses Unspecified Address 0:0:0:0:0:0:0:0 or :: The Loopback Address 0:0:0:0:0:0:0:1 or ::1 Global unicast addresses IPv6 Addresses with Embedded IPv4 Addresses Link-local addresses Site-local addresses Unique Local IPv6 Unicast Addresses
Global Unicast Addresses RFC 4291 標準 m bits global routing prefix RFC 3587 建議 n bits global routing prefix n bits subnet ID 64-n bits subnet ID 128-m-n bits Interface ID 64 bits Interface ID 現行架構 45 bits 16 bits 64 bits 001 global routing prefix subnet ID Interface ID 原 RFC2374 的 Top-Level Aggregation ID Next-Level Aggregation ID (NLA ID) Site-Level Aggregation ID(SLA ID) 架構自 2003/08 以後不復存在 Unicast RCWang 2011
Unicast RCWang 2011 IPv6 Addresses with Embedded IPv4 IPv4-compatible address 0:0:0:0:0:0:w.x.y.z or ::w.x.y.z IPv6 Host IPv6 Host IPv4 Network DST: ::w.x.y.z DST: w.x.y.z DST: ::w.x.y.z 已廢止不用, 但既有設備仍可延用
Unicast RCWang 2011 IPv6 Addresses with Embedded IPv4 IPv4-mapped address 0:0:0:0:0:FFFF:w.x.y.z or ::FFFF:w.x.y.z IPv6 Host IPv4 Host IPv6 Network DST: ::FFFF:w.x.y.z DST: ::FFFF:w.x.y.z DST: w.x.y.z
IPv6 Addresses with Embedded IPv4 RFC6052 /32 prefix IPv4 u suffix /40 prefix IPv4 u v4 suffix Prefix Length /48 /56 prefix prefix IPv4 v4 u u IPv4 IPv4 suffix suffix /64 prefix u IPv4 suffix /96 prefix IPv4 0 32 40 48 56 64 72 80 88 96 104 128 Unicast RCWang 2011
IPv6 Addresses with Embedded IPv4 一般性例子 Network Prefix IPv4 address IPv4-embedded IPv6 address 2001:db8::/32 192.0.2.33 2001:db8:c000:221:: 2001:db8:100::/40 192.0.2.33 2001:db8:1c0:2:21:: 2001:db8:122::/48 192.0.2.33 2001:db8:122:c000:2:2100:: 2001:db8:122:300::/56 192.0.2.33 2001:db8:122:3c0:0:221:: 2001:db8:122:344::/64 192.0.2.33 2001:db8:122:344:c0:2:2100:: 2001:db8:122:344::/96 192.0.2.33 2001:db8:122:344::192.0.2.33 Well-known Prefix Network Prefix IPv4 address IPv4-embedded IPv6 address 64:ff9b::/96 192.0.2.33 64:ff9b::192.0.2.33 Unicast RCWang 2011
Unicast RCWang 2011 Link-local addresses Format Prefix 1111 1110 10 FE80::/10 prefix 10 bits 64 bits 54 bits 1111 1110 10 0 Interface ID 用途 Address Autoconfiguration Neighbor/Router Discovery 路由協定交換用 連接同網段的設備
Site-Local Addresses Format Prefix 1111 1110 11 FEC0::/10 prefix 10 bits 64 bits 54 bits 1111 1110 11 Subnet ID Interface ID 使用在 Intranet 原意在替代 IPv4 private addresses 在路由器應予過濾 已廢止不用, 但既有設備仍可延用 新標準視此位址為 Global Unicast Address Unicast RCWang 2011
Unicast RCWang 2011 Unique Local IPv6 Unicast Addresses RFC 4193 等同 IPv4 的 Private Address 7 bits 1 40 bits 16 bits 64 bits prefix 1 global ID subnet ID Interface ID FC00::/7 pseudo-random
Multicast RCWang 2011 Multicast Addresses 8 bits 4 bits 4 bits 112 bits 11111111 flgs scop group ID 0 依後面的參數決定 1 P=T=1(FF70::/12) Group ID 改採 RFC3956 格式指向 RP 0 R P T 0 依後面的參數決定 1 T=1(FF30::/12) Group ID 改採 RFC3306 格式指向 network prefix 0 永久性 1 臨時的 1 Interface-Local scope 2 Link-Local scope 4 Admin-Local scope 5 Site-Local scope 8 Organization-Local scope E Global scope 0, 3, F reserved 6, 7, 9, A, B, C, D unassigned
Multicast RCWang 2011 Multicast Addresses Scope Node-Local Link-Local Site-Local All Scope FF01:: FF02:: FF05:: FF0x:: RFC2375 ::1 All Nodes ::2 All Routers ::9 RIP Routers ::B Mobile Agents ::1:2 All-dhcp-agents ::1:3 All-dhcp-servers ::101 Network Time Protocol
Multicast RCWang 2011 Solicited Node Addresses Prefix Interface ID FF02 0 0001 FF XXXXXX 16 bits 64 bits 16 bits 8 bits 24 bits
Solicited Node Addresses (cont.) Multicast RCWang 2011
Anycast RCWang 2011 IPv6 Anycast Addresses 使用 Unicast Address 在多個介面上 會計算 longest prefix P 來判定是否有 Anycast 節點 需對路由進行額外設定 (Host Route) 唯一被指定的 Anycast Address 為 Subnet- Router anycast address n bits 128-n bits Subnet Prefix 0
IPv6 Anycast Addresses Anycast RCWang 2011
Anycast 的例子 Anycast RCWang 2011
IPv6 Addressing RCWang 2011 IPv6 Addresses for a Host Unicast addresses: A link-local address for each interface Unicast addresses for each interface (Unique Local or global addresses) A loopback address (::1) Multicast addresses: The node-local scope all-nodes multicast address (FF01::1) The link-local scope all-nodes multicast address (FF02::1) The solicited-node address for each unicast address The multicast addresses of joined groups
IPv6 Addressing RCWang 2011 IPv6 Addresses for a Router Unicast addresses: A link-local address for each interface Unicast addresses for each interface Loopback address (::1) Anycast addresses Subnet-router anycast address Additional anycast addresses (optional) Multicast addresses: The node-local scope all-nodes multicast address (FF01::1) The node-local scope all-routers multicast address (FF01::2) The link-local scope all-nodes multicast address (FF02::1) The link-local scope all-routers multicast address (FF02::2) The site-local scope all-routers multicast address (FF05::2) The solicited-node address for each unicast address The multicast addresses of joined groups
Block Prefix CIDR Block Assignment Fraction 0000 0000 0000::/8 Reserved (IPv4 compatible) 1/256 0000 0001 0100::/8 Reserved 1/256 0000 001 0200::/7 Reserved 1/128 0000 01 0400::/6 Reserved 1/64 0000 1 0800::/5 Reserved 1/32 0001 1000::/4 Reserved 1/16 001 2000::/3 Global unicast 1/8 010 4000::/3 Reserved 1/8 011 6000::/3 Reserved 1/8 100 8000::/3 Reserved 1/8 101 A000::/3 Reserved 1/8 110 C000::/3 Reserved 1/8 1110 E000::/4 Reserved 1/16 1111 0 F000::/5 Reserved 1/32 1111 10 F800::/6 Reserved 1/64 1111 110 FC00::/7 Unique local unicast 1/128 1111 1110 0 FE00::/9 Reserved 1/512 1111 1110 10 FE80::/10 Link local addresses 1/1024 1111 1110 11 FEC0::/10 Reserved 1/1024 1111 1111 FF00::/8 Multicast addresses 1/256 IPv6 Addressing RCWang 2011
Hierarchical Addressing & Aggregation Customer no 1 2001:0410:0001:/48 ISP 2001:0410::/32 Only announces the /32 prefix Customer no 2 2001:0410:0002:/48 IPv6 Internet 2001::/16 Larger address space enables: Aggregation of prefixes announced in the global routing table. Efficient and scalable routing. But current Multi-Homing schemes break the model IPv6 Addressing RCWang 2011
IPv6 Data Link Layer Protocol
IPv6 & Data Link Layer RCWang 2011 Interface Identifiers 128 bits Prefix Interface ID 64 bits Data Link Layers Ethernet RFC 2464, Transmission of IPv6 Packets over Ethernet Networks FDDI RFC 2467, Transmission of IPv6 Packets over FDDI Networks Token Ring RFC 2470, Transmission of IPv6 Packets over Token Ring Networks ATM RFC 2492, IPv6 over ATM Networks PPP RFC 2472, IP Version 6 over PPP Frame Relay RFC 2590, Transmission of IPv6 Packets over Frame Relay Networks NBMA RFC 2491, IPv6 over Non-Broadcast Multiple Access (NBMA) networks ARCnet RFC 2497, Transmission of IPv6 Packets over ARCnet Networks Generic packet tunneling RFC 2473, Generic Packet Tunneling in IPv6 Specification IEEE-1394 RFC 3146, Transmission of IPv6 Packets over IEEE 1394 Networks SONET/SDH RFC 3572, Internet Protocol Version 6 over MAPOS Fibre Channel RFC 4338, Transmission of IPv6, IPv4, and Address Resolution Protocol (ARP) Packets over Fibre Channel
Ethernet Protocol ID IPv6 over Ethernet RCWang 2011
Multicast Mapping over Ethernet IPv6 over Ethernet RCWang 2011
EUI-64 to IPv6 Interface ID IPv6 over Ethernet RCWang 2011
Privacy Expansion IPv6 over Ethernet RCWang 2011
Layer2 Protocol ID Number for IPv6 Ethernet and IP Protocol Numbers RCWang 2011
IPv4 Addresses and IPv6 Equivalents IPv4 Address Internet address classes Multicast addresses (224.0.0.0/4) Broadcast addresses IPv6 Address N/A IPv6 multicast addresses (FF00::/8) N/A Unspecified address is 0.0.0.0 Unspecified address is :: Loopback address is 127.0.0.1 Loopback address is ::1 Public IP addresses Private IP addresses APIPA addresses Dotted decimal notation Subnet mask or prefix length Aggregatable global unicast addresses Site-local addresses (FEC0::/48) Link-local addresses (FE80::/64) Colon hexadecimal format Prefix length notation only Addressing IPv4 vs. IPv6 RCWang 2011
IPv6 Header
Packet Structure RCWang 2011 IPv4 Header RFC791(Internet Protocol Darpa Internet Program Protocol Specification) 於 IPv6 取消或變更的欄位
Packet Structure RCWang 2011 IPv6 Header 32 bits Version Traffic Class Flow Label Payload Length Next Header Hop Limit Source Address Basic Header 40 octets Destination Address Next Header Extension Header Extension Header Variable Length Data Portion
Packet Structure RCWang 2011 IPv6 Header 32 bits Version Traffic Class Flow Label Payload Length Next Header Hop Limit Version Source Address (4 Bits) 表示 Internet Protocol 的版本號碼 IPv6 即為 Destination 0110 Address Basic Header 40 octets Next Header Extension Header Extension Header Variable Length Data Portion
Packet Structure RCWang 2011 IPv6 Header 32 bits Version Traffic Class Flow Label Payload Length Next Header Hop Limit Next Header Traffic Class Source Address (8 Bits) 表示封包的類別或優先度 這個欄位與 Destination IPv4 之 Address Service Type 提供相同的功能 Extension Header Basic Header 40 octets Extension Header Variable Length Data Portion
Packet Structure RCWang 2011 IPv6 Header 32 bits Version Traffic Class Flow Label Payload Length Next Header Hop Limit Next Header Flow Label Source Address (20 Bits) 顯示封包所屬的 Flow 編號 在不支援 Flow Label 欄位的機能的主機或路由 Destination Address 器上, 會使用其預設值 0 Extension Header Basic Header 40 octets Extension Header Variable Length Data Portion
Packet Structure RCWang 2011 IPv6 Header 32 bits Version Traffic Class Flow Label Payload Length Next Header Hop Limit Source Address Payload Length Basic Header 40 octets Next Header (16 Bits) Destination Address 以無號整數表示在 IPv6 基本標頭之後剩下的封包長度, 以 Byte 為單位計算 Extension Header Extension Header Variable Length Data Portion
Packet Structure RCWang 2011 IPv6 Header 32 bits Version Traffic Class Flow Label Payload Length Next Header Hop Limit Source Address Next Header Basic Header 40 octets (8 Bits) 指出下一個標頭的種類 Destination Address Next Header Extension Header Extension Header Variable Length Data Portion
Packet Structure RCWang 2011 IPv6 Header 32 bits Version Traffic Class Flow Label Payload Length Next Header Hop Limit Source Address Hop Limit Basic Header 40 octets Next Header (8 Bits) Destination Address 以無號數表示 IPv6 封包被捨棄之前最多可經過的節點數 Extension Header Extension Header Variable Length Data Portion
Packet Structure RCWang 2011 IPv6 Header 32 bits Version Traffic Class Flow Label Payload Length Next Header Hop Limit Source Address Basic Header 40 octets Source Address Destination Address Next Header (128 Bits) 封包來源的 Extension IPv6 位址 Header Extension Header Variable Length Data Portion
Packet Structure RCWang 2011 IPv6 Header Version Traffic Class Flow Label 32 (128 bits Bits) 封包目的地的 IPv6 位址 一般來說, 會設定為最終目的地的位址, 但若延伸標頭中有 Routing Header 存在時, 則不設定最終目的地, 而是設定於 Source Routing List 所記錄的下一個 Route Interface 的位址 Payload Length Next Header Hop Limit Source Address Destination Address Destination Address Basic Header 40 octets Next Header Extension Header Extension Header Variable Length Data Portion
Packet Structure RCWang 2011 IPv6 Header cap Echo Request Echo Reply fe80::260:97ff:fe02:6e8f fe80::260:97ff:fe02:6d3d
Extension Headers Extension Headers RCWang 2011
Extension Headers RCWang 2011 Extension Headers Next Header (8 Bits) 值 (10 進位 ) Next Header Type 0 Hop By Hop Option Header 6 TCP 17 UDP 41 Capsule IPv6 Header 43 Routing Header 44 Fragment Header 46 Resource Reservation Protocol 50 Security Payload Capsule Header (RFC2406) 51 Authentication Header (RFC2402) 58 ICMPv6 59 No Next Header 60 Destination Option Header
Extension Headers RCWang 2011 Example and Exception IPv6 Header Next Header = 6 (TCP) TCP Segment IPv6 Header Next Header = 43 (Routing) Routing Header Next Header = 6 (TCP) TCP Segment IPv6 Header Next Header = 43 (Routing) Routing Header Next Header = 51 (AH) Authentication Header Next Header = 6 (TCP) TCP Segment 並不是所有的 IPv6 封包都使用延伸標頭 : 當遇到沒有支援的延伸標頭時, 回覆給對方 ICMP Parameter Problem Message (Type=1, Code=1), 將封包捨棄 有延伸標頭, 但附有延伸標頭的 Option 不被支援時, 對 Option 編號要求錯誤處理
Extension Headers RCWang 2011 Extension Headers Standard Hop By Hop Option Header(RFC2460) Routing Header Fragment Header(RFC2460) Destination Option Header(RFC2460) Authentication Header (RFC2402) Security Payload Capsule (ESP:Encapsulating Security Payload) Header (RFC2406) Mobility Header (RFC6275)
Order Order Header Type Next Header Code 1 Basic IPv6 Header - 2 Hop-by-Hop Options 0 3 Destination Options (with Routing Options) 60 4 Routing Header 43 5 Fragment Header 44 6 Authentication Header 51 7 Encapsulation Security Payload Header 50 8 Destination Options 60 9 Mobility Header 135 No next header 59 TCP 6 UDP 17 ICMPv6 58 Extension Headers RCWang 2011
Extension Headers RCWang 2011 Hop By Hop Option Header Next Header (8 Bits) 顯示緊接於 Hop By Hop Option 標頭之後連續標頭的種類 Hdr Ext Len (Header Extension Length) (8 Bits) 以無號數來表示 Hop By Hop Option 標頭的長度, 以 8 Bytes 為單位 這個長度沒有包含 Hop By Hop Option 標頭最初的 8 Bytes Options ( 可變長度 ) 含一個以上以 TLV (Type-Length-Valve) 方式編碼的選項 cap
Extension Headers Options RCWang 2011 Structure of an Option Type 00x 01x 10x 11x xx0 xx1 Action Option Type Option Length Option data... Skip the option Silently discard the packet Discard the packet and send an ICMPv6 parameter problem message to the sender if the destination address field in IPv6 header is a unicast or multicast address Discard the packet and send an ICMPv6 parameter problem message to the sender if the destination address field in IPv6 header is not a multicast address Option data can not change in the path to the destination Option data can change in the path to the destination
Extension Headers Options RCWang 2011 Structure of the Pad1 Option Option Type = 0
Extension Headers Options RCWang 2011 Structure of the PadN Option Option Type = 1 Option Length Option data...
Extension Headers Options RCWang 2011 Structure of the Jumbo Payload Option Option Type Option Length Jumbo Payload Length = 194 = 4
Extension Headers Options RCWang 2011 Structure of the Router Alert Option (RFC2711) Option Type Option Length Router Alert Value = 5 = 2 = 0
Mobility Options Value Description Reference 0 Pad1 [RFC6275] 1 PadN [RFC6275] 2 Binding Refresh Advice [RFC6275] 3 Alternate Care-of Address [RFC6275] 4 Nonce Indices [RFC6275] 5 Authorization Data [RFC6275] 6 Mobile Network Prefix Option [RFC3963] 7 Mobility Header Link-Layer Address option [RFC5568] 8 MN-ID-OPTION-TYPE [RFC4283] 9 AUTH-OPTION-TYPE [RFC4285] 10 MESG-ID-OPTION-TYPE [RFC4285] 11 CGA Parameters Request [RFC4866] 12 CGA Parameters [RFC4866] 13 Signature [RFC4866] 14 Permanent Home Keygen Token [RFC4866] 15 Care-of Test Init [RFC4866] 16 Care-of Test [RFC4866] 17 DNS-UPDATE-TYPE [RFC5026] 18 Experimental Mobility Option [RFC5096] 19 Vendor Specific Mobility Option [RFC5094] 20 Service Selection Mobility Option [RFC5149] 21 Binding Authorization Data for FMIPv6 (BADF) [RFC5568] 22 Home Network Prefix Option [RFC5213] 23 Handoff Indicator Option [RFC5213] 24 Access Technology Type Option [RFC5213] 25 Mobile Node Link-layer Identifier Option [RFC5213] Value Description Reference 26 Link-local Address Option [RFC5213] 27 Timestamp Option [RFC5213] 28 Restart Counter [RFC5847] 29 IPv4 Home Address [RFC5555] 30 IPv4 Address Acknowledgement [RFC5555] 31 NAT Detection [RFC5555] 32 IPv4 Care-of Address [RFC5555] 33 GRE Key Option [RFC5845] 34 Mobility Header IPv6 Address/Prefix [RFC5568] 35 Binding Identifier [RFC5648] 36 IPv4 Home Address Request [RFC5844] 37 IPv4 Home Address Reply [RFC5844] 38 IPv4 Default-Router Address [RFC5844] 39 IPv4 DHCP Support Mode [RFC5844] 40 Context Request Option [RFC5949] 41 Local Mobility Anchor Address Option [RFC5949] 42 Mobile Node Link-local Address Interface Identifier Option [RFC5949] 43 Transient Binding [RFC6058] 44 Flow Summary Mobility Option [RFC6089] 45 Flow Identification Mobility Option [RFC6089] 46 Redirect-Capability Mobility Option [draft-ietf-netextredirect-12] 47 Redirect Mobility Option 48 Load Information Mobility Option 49 Alternate IPv4 Care-of Address Extension Headers Options RCWang 2011
Extension Headers RCWang 2011 Routing Header Next Header (8 Bits) 顯示緊接於 Routing Header 之後連續標頭的種類 Hdr Ext Len (Header Extension Length) (8 Bits) 以無號數來表示標頭的長度, 以 8 Bytes 為單位 Routing Type (8 Bits) 表示特定的路由型態 Segments Left (8 Bits) 以無號數來表示來表示剩餘 Segment 數, 也就是顯示出到達最終目的地必通過之路徑的 Segment 數 Type-Specific Data ( 可變長度 ) 此欄位的內容與型式由指定的 Routing Type 決定
Extension Headers RCWang 2011 Routing Header RFC5871: IANA Allocation Guidelines for the IPv6 Routing Header Type 0: Source Routing, 原 RFC2460 中定義, 在 RFC5095 中被取消 2: Mobile IPv6, RFC6275 253, 254: Experiment, RFC4727
Extension Headers RCWang 2011 Routing Header (Type 2) =2 =2 =1 Reserved = 0 Home Address (128 bits)
Extension Headers RCWang 2011 Fragment Header Next Header (8 Bits) 顯示緊接於 Fragment 標頭之後連續標頭的種類 Reserved (8 Bits) 為被保留之欄位 傳送時為 0, 接收時則忽略掉 Fragment Offset (13 Bit) 無符號整數 相對於原始標頭之分割部分的起點, 跟隨在此標頭之後的資料偏移值, 以 8Bytes 為單位 M Flag (1 Bit) M Flag = 1 尚有 Fragment M Flag = 0 最終的 Fragment Identification (32 Bits) 原本附加於各 Fragment 之識別子, 可於 Packet 再構成時使用
Extension Headers RCWang 2011 IPv6 Fragmentation Process Original IPv6 Packet Unfragmentable part Fragmentable part Unfragmentable part Fragment header First fragment Unfragmentable part Fragment header Second fragment cap Unfragmentable part Fragment header Third fragment
Extension Headers RCWang 2011 IPv6 Reassembly Process Unfragmentable part Fragment header Fragmentable part Unfragmentable part Fragment header Fragmentable part Unfragmentable part Fragment header Fragmentable part Unfragmentable part Fragmentable part Original IPv6 Packet
Extension Headers RCWang 2011 Destination Options Header Next Header (8 Bits) 顯示緊接於 Destination Options Header 之後連續標頭的種類 Hdr Ext Len (Header Extension Length) (8 Bits) 以無號數來表示 Destination Options Header 的長度, 以 8 Bytes 為單位 這個長度沒有包含 Destination Options Header 最初的 8 Bytes Options ( 可變長度 ) 此欄位包含一個以上的 TLV (Type-Length-Valve) 編碼的 Option 選項
Extension Headers RCWang 2011 No Next Header 下一個標頭欄位值為 59 時, 即表示下一個延伸標頭不存在
Extension Headers RCWang 2011 Authentication Header Next Header (8 Bits) 顯示緊接於認證標頭之後連續標頭的種類 Payload Length (8 Bits) 認證標頭的長度, 以 4 Bytes(32 Bits) 單位表示 這個長度沒有包含認證標頭最初的 8 Bytes Reserved (16 Bits) 為被保留之欄位 傳送時為 0, 接收時則忽略掉
Extension Headers RCWang 2011 Authentication Header Security Parameter Index(SPI) (32 Bits) 這個欄位值 (SPI 值 ) 以 32 Bits 的值將此 Datagram 之 Security Association(SA) 指定出來 Sequence Number (32 Bits) 這個欄位為無號數計數器, 是用於防止 SA Replay(anti-replay Protection) 用的 Authentication Data (32 Bits 倍數的可變長度 ) 這個欄位值為以 32 Bits 的整數倍之可變長度, 包含為了檢查此封包的安全性之 Integrity Check Valve 值 (ICV) 無法成為 32 Bits 的整數倍時, 用 Padding 來填補
Security Payload Capsule Header Extension Headers RCWang 2011
Extension Headers RCWang 2011 Security Payload Capsule Header SPI:Security Parameters Index (32 Bits) 這個欄位以任意之 32 Bist 的值將此 Datagram 之 Security Association SA 指示出來之識別子 Sequence Number (32 Bit) 這個欄位為無號數計數器, 是用於防止 SA Replay(antireplay Protection) 用的 Payload Data ( 可變長度 ) 這個欄位值為以 32 Bits 的整數倍之可變長, 包含下一個標頭所顯示之 Data 此 Filed 是必要的 Padding ( 可變長 0~255 Bytes) 這個欄位是被加密所使用 Payload Data 以加密演算法需要之 Block Size 的倍數被填入
Extension Headers RCWang 2011 Security Payload Capsule Header Padding Length (8 Bits) 計算前一個 Padding 的長度, 以 Bytse 為單位 數值範圍是 0~225,0 則表示沒有 Padding Byte 此欄位是必要的 Next Header (8 Bits) 顯示緊接於 Security Payload Capsule Header 之後連續標頭的種類 Authentication Data (32 Bits 倍數的可變長度 ) 這個欄位值為以 32 Bits 的整數倍之可變長度, 包含為了檢查自此 ESP Packet 減去認證標頭後計算之 Packet 的安全性之 Integrity Check Valve 值 (ICV) 無法成為 32 Bit 的整數倍時, 用 Padding 來填補
Mobility Header Value Description Reference 0 Binding Refresh Request [RFC6275] 1 Home Test Init [RFC6275] 2 Care-of Test Init [RFC6275] 3 Home Test [RFC6275] 4 Care-of Test [RFC6275] 5 Binding Update [RFC6275] 6 Binding Acknowledgement [RFC6275] 7 Binding Error [RFC6275] 8 Fast Binding Update [RFC5568] 9 Fast Binding Acknowledgment [RFC5568] 10 Fast Neighbor Advertisement (Deprecated) [RFC5568] 11 Experimental Mobility Header [RFC5096] 12 Home Agent Switch Message [RFC5142] 13 Heartbeat Message [RFC5847] 14 Handover Initiate Message [RFC5568] 15 Handover Acknowledge Message [RFC5568] 16 Binding Revocation Message [RFC5846] Ref: http://www.iana.org/assignments/mobility-parameters/mobility-parameters.xml Extension Headers RCWang 2011
Pseudo-Header RCWang 2011 IPv6 Pseudo-Header Source Address Destination Address Upper Layer Packet Length Zero Next Header = 0
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