Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.
Network layer functions <ul><li>Logical Addressing:  Every device that communicates over a network has associated with it ...
Current Internet Protocol <ul><li>Current version 4 : IPv4  </li></ul><ul><ul><li>Substantially unchanged since 1981:RFC 7...
Longevity of TCP/IP <ul><li>Sound Architecture </li></ul><ul><ul><li>Simple and Open </li></ul></ul><ul><ul><li>Layered </...
Problems with IPv4 <ul><li>IPv4 has been designed early in the 70s </li></ul><ul><li>Many « add-ons» to the protocol : </l...
Problems with IPv4 <ul><li>Impending exhaustion of address space </li></ul><ul><li>Configuration complexities </li></ul><u...
IP Datagram Header VERS HLEN TOS TOTAL LENGTH IDENTIFICATION FLAG FRAGMENT OFFSET TTL PROTOCOL CHECKSUM SOURCE ADDRESS DES...
IP datagram format <ul><li>how much overhead with TCP? </li></ul><ul><li>20 bytes of TCP </li></ul><ul><li>20 bytes of IP ...
IP Fragmentation & Reassembly <ul><li>network links have MTU (max.transfer size) - largest possible link-level frame. </li...
IP Fragmentation and Reassembly <ul><li>Example </li></ul><ul><li>4000 byte datagram </li></ul><ul><li>MTU = 1500 bytes </...
Problems with IPv4: Limited Address Space <ul><li>IPv4 has 32 bit addresses. </li></ul><ul><li>Flat addressing (only netid...
 
Problems with IPv4: Routing Table Explosion <ul><li>IP does not permit route aggregation </li></ul><ul><li>(limited supern...
IP Datagram Header VERS HLEN TOS TOTAL LENGTH IDENTIFICATION FLAG FRAGMENT OFFSET TTL PROTOCOL CHECKSUM SOURCE ADDRESS DES...
Problems with IPv4: Header Limitations <ul><li>Maximum header length is 60 octets. </li></ul><ul><li>(Restricts options) <...
Problems with IPv4: Other Limitations <ul><li>Lack of quality-of-service support. </li></ul><ul><ul><li>Only an 8-bit ToS ...
Problems with IPv4: Inadequate support to newer applications <ul><li>Many applications larger than Web </li></ul><ul><ul><...
Extended Life for IPv4 <ul><li>Strict monitoring of  IP address assignment </li></ul><ul><li>Private IP addresses for intr...
Next generation IP:IPng Security Issues
IPv6: Distinctive Features <ul><li>Header format simplification </li></ul><ul><li>Expanded routing and addressing capabili...
IPng Criteria <ul><li>At least 10 9  networks, 10 12  end-systems </li></ul><ul><li>Datagram service (best effort delivery...
IPng Criteria <ul><li>Support for mobile nodes </li></ul><ul><li>Support for quality-of-service </li></ul><ul><li>Provide ...
IPv6 road map Feb 1992  Dec 1992  March 1993  May 1993  Nov 1993 Simple CLNP  TUBA Nimrod CNAT IP encaps  IPAE  SIP  SIPP ...
IPv6 RFCs <ul><li>Internet Protocol, version 6 (IPv6) Specication , RFC-2460 [IPv6] </li></ul><ul><li>IPv6 Addressing Arch...
IPv6 RFCs <ul><li>Internet Protocol, version 6 (IPv6) Specication , RFC-2460 [IPv6] </li></ul><ul><li>IPv6 Addressing Arch...
IPv4 header to IPv6 header Source address Destination Address Payload Length Next Header Ver Hop Limit Traffic class Flow ...
IPv6 Header Fields <ul><li>Version number (4-bit field)  </li></ul><ul><li>The value is always 6. </li></ul><ul><li>Flow l...
IPv6 Header Fields <ul><li>Hop limit (8-bit field) </li></ul><ul><li>Decremented by 1 by each node that forwards the packe...
Header Changes from IPv4 <ul><li>Longer address -  32 bits    128 bits </li></ul><ul><li>Fragmentation field moved to sep...
Extension Headers <ul><li>Less used functions moved to extension headers. </li></ul><ul><li>Only present when needed. </li...
Extension Headers
IPv6 Core Protocols:  IPv6 Extension Headers <ul><li>Order of Extension Headers when more than one is used in same packet:...
Address Types <ul><li>Unicast Address for a single interface. </li></ul><ul><li>( one to one) </li></ul><ul><li>Multicast ...
Text Representation of Addresses <ul><li>HEX in blocks of 16 bits </li></ul><ul><li>BC84 : 25C2 : 0000 : 0000 : 0000 : 55A...
Unicast IPv6 addresses:  <ul><li>Global unicast addresses </li></ul><ul><li>Link-local addresses </li></ul><ul><li>Site-lo...
Global Unicast Addresses
Link-Local Addresses FE80::/64
Site-Local Addresses FEC0::/10
Special addresses <ul><li>The unspecified address  </li></ul><ul><ul><li>0:0:0:0:0:0:0:0 or :: </li></ul></ul><ul><ul><li>...
Compatible addresses <ul><li>The IPv4-compatible address </li></ul><ul><ul><li>0:0:0:0:0:0: w.x.y.z  or :: w.x.y.z </li></...
Interface ID
MAC address format
Mapping IEEE 802 Addresses to EUI-64 Addresses
Anycast address overview <ul><li>Types of Addresses in IPv6/IPv4 </li></ul><ul><ul><li>Unicast – one to one </li></ul></ul...
Anycast address & use <ul><li>Allocated from unicast address space </li></ul><ul><ul><li>Link local, site local, global </...
Anycast address restrictions <ul><li>Cannot be used as a source address </li></ul><ul><li>Cannot be assigned to a host </l...
Multicasting <ul><li>One to many addressing </li></ul><ul><li>Delivery of packets to many destinations </li></ul><ul><ul><...
IPv4 multicast address Class D <ul><li>Range from 224.0.0.0 through 239.255.255.255 </li></ul><ul><li>A set of hosts liste...
Special multicast addresses <ul><li>224.0.0.0   Reserved; not used </li></ul><ul><li>224.0.0.1 All devices on the subnet <...
Ethernet Multicast address <ul><li>Host group to multicast source </li></ul><ul><ul><li>IP : group IP address </li></ul></...
Mapping of class D IP address into Ethernet Multicast Address <ul><li>IANA has allotted 01:00:5e:00:00:00 through 01:00:5e...
IPv6 Multicast address <ul><li>Format prefix : FF </li></ul><ul><li>Flags: 000T </li></ul><ul><ul><li>T= 0: well known per...
IPv6 Multicast address <ul><li>Group ID  – Identifies the multicast group and is unique within the scope </li></ul><ul><ul...
Mapping IPv6 Multicast Addresses to Ethernet Addresses When sending IPv6 multicast packets on an Ethernet link, the corres...
Solicited node multicast address <ul><li>Format: FF02:0:0:0:0:1:FFXX:XXXX </li></ul><ul><li>It is formed by taking the low...
An IPv6 Node’s multi cast addresses <ul><li>For example, a host with the Ethernet MAC address of 00-AA-00-3F-2A-1C (link-l...
THANK YOU For your patient hearing
Upcoming SlideShare
Loading in …5
×

Network Layer And I Pv6

2,598 views

Published on

Unit 2 Of ACN

Published in: Technology
  • Be the first to comment

  • Be the first to like this

Network Layer And I Pv6

  1. 1. Network layer functions <ul><li>Logical Addressing: Every device that communicates over a network has associated with it a logical address, sometimes called a layer three address. On the Internet every machine has an IP address . L ogical addresses are independent of particular hardware and must be unique across an entire internetwork. </li></ul><ul><li>Routing: Moving data across a series of interconnected networks is an important function of the network layer. </li></ul><ul><li>Datagram Encapsulation: The network layer normally encapsulates messages received from higher layers by placing them into datagrams (also called packets ) with a network layer header. </li></ul><ul><li>Fragmentation and Reassembly: The network layer must send messages down to the data link layer for transmission. If the packet that the network layer wants to send is too large, the network layer must split the packet up, send each piece to the data link layer, and then have pieces reassembled once they arrive at the network layer on the destination machine. </li></ul><ul><li>Error Handling and Diagnostics: Special protocols are used at the network layer to allow devices that are logically connected to exchange inform ation about the status of hosts on the network or the devices thems elves </li></ul>
  2. 2. Current Internet Protocol <ul><li>Current version 4 : IPv4 </li></ul><ul><ul><li>Substantially unchanged since 1981:RFC 791 </li></ul></ul><ul><ul><li>Proven to be robust, easily implemented and interoperable </li></ul></ul><ul><ul><li>Stood the test of time for over two decades </li></ul></ul><ul><ul><li>A tribute to its initial design </li></ul></ul><ul><li>IPv4 lead to wired networks </li></ul><ul><ul><li>in business and in homes </li></ul></ul><ul><ul><li>leaving mainframes behind </li></ul></ul>
  3. 3. Longevity of TCP/IP <ul><li>Sound Architecture </li></ul><ul><ul><li>Simple and Open </li></ul></ul><ul><ul><li>Layered </li></ul></ul><ul><li>Open standard </li></ul><ul><li>Good Support systems </li></ul><ul><ul><li>Communication </li></ul></ul><ul><ul><li>Technology growth </li></ul></ul><ul><li>Prerogative of US </li></ul>
  4. 4. Problems with IPv4 <ul><li>IPv4 has been designed early in the 70s </li></ul><ul><li>Many « add-ons» to the protocol : </li></ul><ul><ul><li>Mobileip </li></ul></ul><ul><ul><li>QoS </li></ul></ul><ul><ul><li>Security (IPsec) </li></ul></ul><ul><ul><li>Others </li></ul></ul><ul><li>Using « add-ons » not easy </li></ul>
  5. 5. Problems with IPv4 <ul><li>Impending exhaustion of address space </li></ul><ul><li>Configuration complexities </li></ul><ul><li>Poor security at the IP level </li></ul><ul><li>Inadequate QoS support for real-time delivery of data. </li></ul>
  6. 6. IP Datagram Header VERS HLEN TOS TOTAL LENGTH IDENTIFICATION FLAG FRAGMENT OFFSET TTL PROTOCOL CHECKSUM SOURCE ADDRESS DESTINATION ADDRESS OPTIONS (if any) + PADDING 0 4 8 16 19 31
  7. 7. IP datagram format <ul><li>how much overhead with TCP? </li></ul><ul><li>20 bytes of TCP </li></ul><ul><li>20 bytes of IP </li></ul><ul><li>= 40 bytes + app layer overhead </li></ul>ver length 32 bits data (variable length, typically a TCP or UDP segment) 16-bit identifier header checksum time to live 32 bit source IP address IP protocol version number header length (bytes) max number remaining hops (decremented at each router) for fragmentation/ reassembly total datagram length (bytes) upper layer protocol to deliver payload to head. len type of service “ type” of data flgs fragment offset upper layer 32 bit destination IP address Options (if any) E.g. timestamp, record route taken, specify list of routers to visit.
  8. 8. IP Fragmentation & Reassembly <ul><li>network links have MTU (max.transfer size) - largest possible link-level frame. </li></ul><ul><ul><li>different link types, different MTUs </li></ul></ul><ul><li>large IP datagram divided (“fragmented”) within net </li></ul><ul><ul><li>one datagram becomes several datagrams </li></ul></ul><ul><ul><li>“ reassembled” only at final destination </li></ul></ul><ul><ul><li>IP header bits used to identify, order related fragments </li></ul></ul>fragmentation: in: one large datagram out: 3 smaller datagrams reassembly
  9. 9. IP Fragmentation and Reassembly <ul><li>Example </li></ul><ul><li>4000 byte datagram </li></ul><ul><li>MTU = 1500 bytes </li></ul>1480 bytes in data field offset = 1480/8 ID =x offset =0 fragflag =0 length =4000 ID =x offset =0 fragflag =1 length =1500 ID =x offset =185 fragflag =1 length =1500 ID =x offset =370 fragflag =0 length =1040 One large datagram becomes several smaller datagrams
  10. 10. Problems with IPv4: Limited Address Space <ul><li>IPv4 has 32 bit addresses. </li></ul><ul><li>Flat addressing (only netid + hostid with “fixed” boundaries). </li></ul><ul><li>Results in inefficient use of address space. </li></ul><ul><li>Class B addresses are almost over. </li></ul><ul><li>Addresses will exhaust very shortly. </li></ul><ul><li>IPv4 is victim of its own success. </li></ul>
  11. 12. Problems with IPv4: Routing Table Explosion <ul><li>IP does not permit route aggregation </li></ul><ul><li>(limited supernetting possible with new routers) </li></ul><ul><li>Mostly only class C addresses remain </li></ul><ul><li>Number of networks is increasing very fast </li></ul><ul><li>(number of routes to be advertised goes up) </li></ul><ul><li>Very high routing overhead </li></ul><ul><ul><li>lot more memory needed for routing table </li></ul></ul><ul><ul><li>lot more bandwidth to pass routing information </li></ul></ul><ul><ul><li>lot more processing needed to compute routes </li></ul></ul>
  12. 13. IP Datagram Header VERS HLEN TOS TOTAL LENGTH IDENTIFICATION FLAG FRAGMENT OFFSET TTL PROTOCOL CHECKSUM SOURCE ADDRESS DESTINATION ADDRESS OPTIONS (if any) + PADDING 0 4 8 16 19 31
  13. 14. Problems with IPv4: Header Limitations <ul><li>Maximum header length is 60 octets. </li></ul><ul><li>(Restricts options) </li></ul><ul><li>Maximum packet length is 64K octets. </li></ul><ul><li>(Do we need more than that ?) </li></ul><ul><li>ID for fragments is 16 bits. Repeats every 65537th packet. </li></ul><ul><li> (Will two packets in the network have same ID?) </li></ul><ul><li>Variable size header. </li></ul><ul><li>(Slower processing at routers.) </li></ul><ul><li>No ordering of options. </li></ul><ul><li>(All routers need to look at all options.) </li></ul>
  14. 15. Problems with IPv4: Other Limitations <ul><li>Lack of quality-of-service support. </li></ul><ul><ul><li>Only an 8-bit ToS field, which is hardly used. </li></ul></ul><ul><ul><li>Problem for multimedia services. </li></ul></ul><ul><li>No support for security at IP layer. </li></ul><ul><li>Mobility support is limited. </li></ul>
  15. 16. Problems with IPv4: Inadequate support to newer applications <ul><li>Many applications larger than Web </li></ul><ul><ul><li>VoIP, 3G, P2P (gaming, file sharing, ..) </li></ul></ul><ul><ul><li>Grid Computing, Ad hoc networks, networked RFIDs </li></ul></ul><ul><ul><li>Remote sensing, Intelligent Transport Systems (ITS) </li></ul></ul><ul><ul><li>Smart Homes, Mobile devices, Consumer Electronics, Home appliances </li></ul></ul>
  16. 17. Extended Life for IPv4 <ul><li>Strict monitoring of IP address assignment </li></ul><ul><li>Private IP addresses for intranets </li></ul><ul><ul><li>Only class C or a part of class C to an organization </li></ul></ul><ul><ul><li>Encourage use of proxy services </li></ul></ul><ul><ul><ul><li>Application level proxies </li></ul></ul></ul><ul><ul><ul><li>Network Address Translation (NAT) </li></ul></ul></ul><ul><li>Remaining class A addresses may use CIDR </li></ul><ul><li>Reserved addresses may be assigned </li></ul><ul><li>But these will only postpone address exhaustion. </li></ul><ul><li>They do not address problems like QoS, mobility, security. </li></ul>
  17. 18. Next generation IP:IPng Security Issues
  18. 19. IPv6: Distinctive Features <ul><li>Header format simplification </li></ul><ul><li>Expanded routing and addressing capabilities </li></ul><ul><li>Improved support for extensions and options </li></ul><ul><li>Flow labeling (for QoS) capability </li></ul><ul><li>Auto-configuration and Neighbour discovery </li></ul><ul><li>Authentication and privacy capabilities </li></ul><ul><li>Simple transition from IPv4 </li></ul>
  19. 20. IPng Criteria <ul><li>At least 10 9 networks, 10 12 end-systems </li></ul><ul><li>Datagram service (best effort delivery) </li></ul><ul><li>Independent of physical layer technologies </li></ul><ul><li>Robust (routing) in presence of failures </li></ul><ul><li>Flexible topology (e.g., dual-homed nets) </li></ul><ul><li>Better routing structures (e.g., aggregation) </li></ul><ul><li>High performance (fast switching) </li></ul><ul><li>Support for multicasting </li></ul>
  20. 21. IPng Criteria <ul><li>Support for mobile nodes </li></ul><ul><li>Support for quality-of-service </li></ul><ul><li>Provide security at IP layer </li></ul><ul><li>Extensible </li></ul><ul><li>Auto-configuration (plug-and--play) </li></ul><ul><li>Straight-forward transition plan from IPv4 </li></ul><ul><li>Minimal changes to upper layer protocols </li></ul>
  21. 22. IPv6 road map Feb 1992 Dec 1992 March 1993 May 1993 Nov 1993 Simple CLNP TUBA Nimrod CNAT IP encaps IPAE SIP SIPP SIP PIP TP/IX CATNIP
  22. 23. IPv6 RFCs <ul><li>Internet Protocol, version 6 (IPv6) Specication , RFC-2460 [IPv6] </li></ul><ul><li>IPv6 Addressing Architecture [RFC-2373] </li></ul><ul><li>Neighbor Discovery for IPv6 [RFC-2461] </li></ul><ul><li>IPv6 Stateless Address Autoconguration [RFC-2462] </li></ul><ul><li>Internet Control Message Protocol (ICMPv6) for IPv6 [RFC-2463] </li></ul><ul><li>Path MTU Discovery for IPv6 [RFC-1981] </li></ul><ul><li>Since the version number assigned by IANA was 6, the short name used for the Internet Protocol version 6 is IPv6. </li></ul>
  23. 24. IPv6 RFCs <ul><li>Internet Protocol, version 6 (IPv6) Specication , RFC-2460 [IPv6] </li></ul><ul><li>IPv6 Addressing Architecture [RFC-2373] </li></ul><ul><li>Neighbor Discovery for IPv6 [RFC-2461] </li></ul><ul><li>IPv6 Stateless Address Autoconguration [RFC-2462] </li></ul><ul><li>Internet Control Message Protocol (ICMPv6) for IPv6 [RFC-2463] </li></ul><ul><li>Path MTU Discovery for IPv6 [RFC-1981] </li></ul><ul><li>Since the version number assigned by IANA was 6, the short name used for the Internet Protocol version 6 is IPv6. </li></ul>
  24. 25. IPv4 header to IPv6 header Source address Destination Address Payload Length Next Header Ver Hop Limit Traffic class Flow Label
  25. 26. IPv6 Header Fields <ul><li>Version number (4-bit field) </li></ul><ul><li>The value is always 6. </li></ul><ul><li>Flow label (20-bit field) </li></ul><ul><li>Used to label packets requesting special handling by routers. </li></ul><ul><li>Traffic class (8-bit field) </li></ul><ul><li>Used to mark classes of traffic. </li></ul><ul><li>Payload length (16-bit field) </li></ul><ul><li>Length of the packet following the IPv6 header, in octets. </li></ul><ul><li>Next header (8-bit field) </li></ul><ul><li>The type of header immediately following the IPv6 header. </li></ul>
  26. 27. IPv6 Header Fields <ul><li>Hop limit (8-bit field) </li></ul><ul><li>Decremented by 1 by each node that forwards the packet. </li></ul><ul><li>Packet discarded if hop limit is decremented to zero. </li></ul><ul><li>Source Address (128-bit field) </li></ul><ul><li>An address of the initial sender of the packet. </li></ul><ul><li>Destination Address (128-bit field) </li></ul><ul><li>An address of the intended recipient of the packet. May not be the ultimate recipient, if Routing Header is present. </li></ul>
  27. 28. Header Changes from IPv4 <ul><li>Longer address - 32 bits  128 bits </li></ul><ul><li>Fragmentation field moved to separate header </li></ul><ul><li>Header checksum removed </li></ul><ul><li>Header length removed (fixed length header) </li></ul><ul><li>Length field excludes IPv6 header </li></ul><ul><li>Time to live  Hop limit </li></ul><ul><li>Protocol  Next header </li></ul><ul><li>64-bit field alignment </li></ul><ul><li>TOS replaced by flow label, traffic class </li></ul>
  28. 29. Extension Headers <ul><li>Less used functions moved to extension headers. </li></ul><ul><li>Only present when needed. </li></ul><ul><li>Processed only by node identified in IPv6 destination field. </li></ul><ul><li>=> much lower overhead than IPv4 options </li></ul><ul><li>Exception: Hop-by-Hop option header </li></ul><ul><li>Eliminated IPv4’s 40-byte limit on options </li></ul><ul><li>Order of extension headers in a packet is defined. </li></ul><ul><li>Headers are aligned on 8-byte boundaries. </li></ul>
  29. 30. Extension Headers
  30. 31. IPv6 Core Protocols: IPv6 Extension Headers <ul><li>Order of Extension Headers when more than one is used in same packet: </li></ul><ul><ul><ul><li>IPv6 Header </li></ul></ul></ul><ul><ul><ul><li>Hop-by-hop Options Header </li></ul></ul></ul><ul><ul><ul><li>Destination Options Header ( every Routing Header destination) </li></ul></ul></ul><ul><ul><ul><li>Routing Header </li></ul></ul></ul><ul><ul><ul><li>Fragment Header </li></ul></ul></ul><ul><ul><ul><li>Authentication Header (AH) </li></ul></ul></ul><ul><ul><ul><li>Encapsulation Security Payload (ESP) Header </li></ul></ul></ul><ul><ul><ul><li>Destination Options Header ( last Routing Header destination) </li></ul></ul></ul><ul><ul><ul><li>Upper-Layer Header </li></ul></ul></ul>TCP Header + Data Payload IPv6 Header Next Header = Routing Fragment Header Next Header = Security (ESP) Security Header (ESP) Next Header = TCP Routing Header Next Header = Fragment
  31. 32. Address Types <ul><li>Unicast Address for a single interface. </li></ul><ul><li>( one to one) </li></ul><ul><li>Multicast Identifier for a set of interfaces. </li></ul><ul><li>Packet is sent to all these interfaces. </li></ul><ul><li>( one to many) </li></ul><ul><li>Anycast Identifier for a set of interfaces. </li></ul><ul><li>Packet is sent to the nearest one. </li></ul><ul><li>( one to one of many) </li></ul>
  32. 33. Text Representation of Addresses <ul><li>HEX in blocks of 16 bits </li></ul><ul><li>BC84 : 25C2 : 0000 : 0000 : 0000 : 55AB : 5521 : 0018 </li></ul><ul><li>leading zero suppression </li></ul><ul><li>BC84 : 25C2 : 0 : 0 :55AB : 5521 : 18 </li></ul><ul><li>Compressed format removes strings of 0 s </li></ul><ul><li>BC84 : 25C2 :: 55AB : 5521 : 18 </li></ul><ul><li>:: can appear only once in an address. </li></ul><ul><li>can also be used to compress leading or trailing 0 s </li></ul><ul><li>Mixed Notation (X:X:X:X:X:X:d.d.d.d) </li></ul><ul><li>e.g., ::144.16.162.21 </li></ul>
  33. 34. Unicast IPv6 addresses: <ul><li>Global unicast addresses </li></ul><ul><li>Link-local addresses </li></ul><ul><li>Site-local addresses </li></ul><ul><li>Special addresses </li></ul><ul><li>Compatible addresses </li></ul>
  34. 35. Global Unicast Addresses
  35. 36. Link-Local Addresses FE80::/64
  36. 37. Site-Local Addresses FEC0::/10
  37. 38. Special addresses <ul><li>The unspecified address </li></ul><ul><ul><li>0:0:0:0:0:0:0:0 or :: </li></ul></ul><ul><ul><li>only used to indicate the absence of an address. </li></ul></ul><ul><ul><li>Equivalent to the IPv4 unspecified address of 0.0.0.0. </li></ul></ul><ul><ul><li>It is typically used as a source address for packets attempting to verify the uniqueness of a tentative address. </li></ul></ul><ul><li>The loop back address </li></ul><ul><ul><li>0:0:0:0:0:0:0:1 or ::1 </li></ul></ul><ul><ul><li>Enables a node to send packets to itself. </li></ul></ul><ul><ul><li>Equivalent to the IPv4 loop back address 127.0.0.1 </li></ul></ul>
  38. 39. Compatible addresses <ul><li>The IPv4-compatible address </li></ul><ul><ul><li>0:0:0:0:0:0: w.x.y.z or :: w.x.y.z </li></ul></ul><ul><ul><ul><li>w.x.y.z is the dotted decimal representation of an IPv4 address </li></ul></ul></ul><ul><ul><li>Used by IPv6/IPv4 nodes that are communicating using IPv6 </li></ul></ul><ul><ul><li>For auto tunneling over IPv4 infrastructure </li></ul></ul><ul><li>The IPv4-mapped address </li></ul><ul><ul><li>0:0:0:0:0:FFFF: w.x.y.z or ::FFFF: w.x.y.z </li></ul></ul><ul><ul><li>Only for internal representations </li></ul></ul><ul><li>The 6to4 address </li></ul><ul><ul><li>Formed by combining the prefix 2002::/16 & 32 bit IPv4 address to get a 48 bit prefix </li></ul></ul><ul><ul><li>Used for configured tunneling over IPv4 infrastructure between two IPv6/IPv4 nodes. </li></ul></ul>
  39. 40. Interface ID
  40. 41. MAC address format
  41. 42. Mapping IEEE 802 Addresses to EUI-64 Addresses
  42. 43. Anycast address overview <ul><li>Types of Addresses in IPv6/IPv4 </li></ul><ul><ul><li>Unicast – one to one </li></ul></ul><ul><ul><li>Multicast – one to many </li></ul></ul><ul><ul><li>Broadcast – one to all ( only in IPv4 ) </li></ul></ul><ul><ul><li>Anycast – one to one of many ( Only in IPv6) </li></ul></ul><ul><li>A new type in IPv6. Not defined for IPv4 </li></ul><ul><li>It is assigned to more than one interface </li></ul><ul><li>Refers to one among many address </li></ul><ul><ul><li>A packet sent to an anycast address is routed to the nearest interface with that address. </li></ul></ul>
  43. 44. Anycast address & use <ul><li>Allocated from unicast address space </li></ul><ul><ul><li>Link local, site local, global </li></ul></ul><ul><li>It is an unicast address assigned to many interfaces </li></ul><ul><li>Nodes with anycast address must be explicitly configured to receive anycast packets. </li></ul><ul><li>Used to identify </li></ul><ul><ul><li>a set of routers of an ISP </li></ul></ul><ul><ul><li>a set of routers in a subnet </li></ul></ul><ul><ul><li>A set of routers providing entry to a routing domain </li></ul></ul>
  44. 45. Anycast address restrictions <ul><li>Cannot be used as a source address </li></ul><ul><li>Cannot be assigned to a host </li></ul><ul><li>May be assigned to a router only </li></ul>
  45. 46. Multicasting <ul><li>One to many addressing </li></ul><ul><li>Delivery of packets to many destinations </li></ul><ul><ul><li>Interactive conferencing </li></ul></ul><ul><ul><li>Dissemination of mail </li></ul></ul><ul><ul><li>News to multiple recepients </li></ul></ul><ul><ul><li>Webcasts to multiple registered recipients </li></ul></ul><ul><ul><li>Location of servers by clients </li></ul></ul>
  46. 47. IPv4 multicast address Class D <ul><li>Range from 224.0.0.0 through 239.255.255.255 </li></ul><ul><li>A set of hosts listening to a IP multicast address is called a host group </li></ul><ul><li>A host group can span multiple networks </li></ul><ul><li>Membership to a host group is dynamic </li></ul><ul><li>No restriction on number of hosts to a group </li></ul><ul><li>Non member can send a message to a group </li></ul>1 1 1 0 28 bit multicast gp ID
  47. 48. Special multicast addresses <ul><li>224.0.0.0 Reserved; not used </li></ul><ul><li>224.0.0.1 All devices on the subnet </li></ul><ul><li>224.0.0.2 All routers on the subnet </li></ul><ul><li>224.0.0.11 Mobile agents (for Mobile IP) </li></ul><ul><li>224.0.0.12 DHCP Server / Relay Agent </li></ul>
  48. 49. Ethernet Multicast address <ul><li>Host group to multicast source </li></ul><ul><ul><li>IP : group IP address </li></ul></ul><ul><ul><li>MAC : next hop address </li></ul></ul><ul><li>Multicast source to Host group </li></ul><ul><ul><li>IP : group IP address </li></ul></ul><ul><ul><li>MAC : Ethernet multicast address </li></ul></ul>
  49. 50. Mapping of class D IP address into Ethernet Multicast Address <ul><li>IANA has allotted 01:00:5e:00:00:00 through 01:00:5e:7f:ff:ff for multicast </li></ul><ul><li>Lower order 23 bits if gp id copied to ethernet address </li></ul><ul><li>Eg1: 224.128.64.32 (hex e0.80.40.20) maps to hex 01:00:5e:00:40:20 </li></ul><ul><li>Eg2 : 224.0.64.32 (hex e0.00.40.20) also maps to hex 01:00:5e:00:40:20 </li></ul>IEEE 802 address
  50. 51. IPv6 Multicast address <ul><li>Format prefix : FF </li></ul><ul><li>Flags: 000T </li></ul><ul><ul><li>T= 0: well known permanent </li></ul></ul><ul><ul><li>T=1: temporary </li></ul></ul><ul><li>Scope: 0 to 15 </li></ul><ul><ul><li>0: reserved </li></ul></ul><ul><ul><li>1: interface local </li></ul></ul><ul><ul><li>2: link local </li></ul></ul><ul><ul><li>3 : reserved </li></ul></ul><ul><ul><li>4 : admin local </li></ul></ul><ul><ul><li>5 : site local </li></ul></ul><ul><ul><li>8 : org local </li></ul></ul><ul><ul><li>E : global </li></ul></ul><ul><ul><li>F : reserved </li></ul></ul>Multicast address structure
  51. 52. IPv6 Multicast address <ul><li>Group ID – Identifies the multicast group and is unique within the scope </li></ul><ul><ul><li>Two well known group IDs </li></ul></ul><ul><ul><ul><li>1 : all nodes </li></ul></ul></ul><ul><ul><ul><li>2 : all routers </li></ul></ul></ul><ul><li>Examples: </li></ul><ul><ul><li>FF01::1 (interface-local scope all-nodes multicast address) </li></ul></ul><ul><ul><li>FF02::1 (link-local scope all-nodes multicast address) </li></ul></ul><ul><ul><li>FF01::2 (interface-local scope all-routers multicast address) </li></ul></ul><ul><ul><li>FF02::2 (link-local scope all-routers multicast address) </li></ul></ul><ul><ul><li>FF05::2 (site-local scope all-routers multicast address) </li></ul></ul>
  52. 53. Mapping IPv6 Multicast Addresses to Ethernet Addresses When sending IPv6 multicast packets on an Ethernet link, the corresponding destination MAC address is 33-33-mm-mm-mm-mm where mm-mm-mm-mm is a direct mapping of the last 32 bits of the IPv6 multicast address, as shown in Figure above
  53. 54. Solicited node multicast address <ul><li>Format: FF02:0:0:0:0:1:FFXX:XXXX </li></ul><ul><li>It is formed by taking the lower order 24 bits of ( unicast or anycast ) </li></ul><ul><li>When A node n1 which wants to find MAC address of node n2, it will send neighbor solicitation message with solicited multicast address to n2. </li></ul><ul><li>Node n2 will reply with neighbor advertisement message </li></ul>
  54. 55. An IPv6 Node’s multi cast addresses <ul><li>For example, a host with the Ethernet MAC address of 00-AA-00-3F-2A-1C (link-local address of FE80::2AA:FF:FE3F:2A1C) registers the following multicast MAC addresses with the Ethernet adapter: </li></ul><ul><li>          The address of 33-33-00-00-00-01, which corresponds to the link-local scope all-nodes multicast address of FF02::1. </li></ul><ul><li>          The address of 33-33-FF-3F-2A-1C, which corresponds to the solicited-node address of FF02::1:FF3F:2A1C. Remember that the solicited-node address is the prefix FF02::1:FF00:0/104 and the last 24-bits of the unicast IPv6 address. </li></ul>
  55. 56. THANK YOU For your patient hearing

×