Unit 1 Introduction From IPv 4 to IPv

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Unit 1: Introduction. From IPv 4 to IPv 6 • Introduction: – Internet Evolution

Unit 1: Introduction. From IPv 4 to IPv 6 • Introduction: – Internet Evolution – The need for high-speed, high-capacity networks with quality-ofservice (Qo. S) guarantees – Protocol and implementation: a simple example • IPv 6 – – – Goals Main Features Main Header Address Formats and Notation Extension Header Transition from IPv 4 to IPv 6 • Dual stack • Header translation • Tunneling – Configured – Automatic TDC 563 -98 -201/202, Winter 2002 1 -1

Introduction: Internet Evolution Year Event 1966 APRA packet-switching experimentation 1969 First ARPANET nodes operational

Introduction: Internet Evolution Year Event 1966 APRA packet-switching experimentation 1969 First ARPANET nodes operational 1972 Distributed e-mail invented 1973 First non-U. S. computer linked to ARPANET 1975 ARPAET transitioned to Defense Communications Agency 1980 TCP/IP experimentation begins 1981 New host added every 20 days 1983 TCP/IP switchover complete 1986 NSFnet backbone created 1990 ARPANET retired 1991 Gopher introduced 1991 WWW invented 1991 PGP (Pretty Good Privacy) released 1992 Mosaic introduced 1995 Internet backbone privatized 1996 OC-3 (155 Mbps) backbone built 1998 Number of registered domain names exceeds 2 million 2000 Number of indexable web pages exceeds 1 billion TDC 563 -98 -201/202, Winter 2002 1 -2

TDC 563 -98 -201/202, Winter 2002 1 -3

TDC 563 -98 -201/202, Winter 2002 1 -3

The need for high-speed, high-capacity networks with quality-of-service (Qo. S) guarantees Availability of Web-based

The need for high-speed, high-capacity networks with quality-of-service (Qo. S) guarantees Availability of Web-based applications that are palatable to the end user Increased speed and efficiency of networks and the Internet Increase in traffic volume generated by users • Emergence of High-Speed LANs • Corporate Wide Area Networking needs: from centralized to network-centric • Digital electronics: DVD, digital cameras etc. TDC 563 -98 -201/202, Winter 2002 1 -4

Qo. S on the Internet TDC 563 -98 -201/202, Winter 2002 1 -5

Qo. S on the Internet TDC 563 -98 -201/202, Winter 2002 1 -5

To provide Qo. S • Two emerging changes to the internet architecture • ISA

To provide Qo. S • Two emerging changes to the internet architecture • ISA (Integrated Services Architecture) • Differentiating Services (DS) • Involve upgrading router hardware and involve a number of new protocols • IPv 6: it provides features that are useful to ISA and DS • RSVP: The Resource Re. Servation Protocol – Key element of ISA • RTP: The Real-Time Transport Protocol • Multicast routing protocols TDC 563 -98 -201/202, Winter 2002 1 -6

Network Protocols = agreed-upon ways in which computers exchange information ·Syntax: structure or format

Network Protocols = agreed-upon ways in which computers exchange information ·Syntax: structure or format of the data ·Semantics: meanings ·Timing: when data should be sent and how fast it can be sent. A simple example protocol and its implementation: SLIP TDC 563 -98 -201/202, Winter 2002 1 -7

SLIP (Serial Line IP): RFC 1055 ·Character-oriented ·END IP-packet END … ·Character stuffing The

SLIP (Serial Line IP): RFC 1055 ·Character-oriented ·END IP-packet END … ·Character stuffing The following C language function sends SLIP packets. They depend on two functions, send_char() and recv_char(), which send and receive a single character over the serial line. /* SLIP special character codes */ #define END 0300 /* indicates end of packet */ #define ESC 0333 /* indicates byte stuffing */ #define ESC_END 0334 /* ESC_END means END data byte */ #define ESC_ESC 0335 /* ESC_ESC means ESC data byte */ TDC 563 -98 -201/202, Winter 2002 1 -8

/* for each byte in the packet, send the appropriate character * sequence */

/* for each byte in the packet, send the appropriate character * sequence */ while(len--) { switch(*p) { /* if it's the same code as an END character, we send a * special two character code so as not to make the * receiver think we sent an END */ case END: send_char(ESC); send_char(ESC_END); break; /* if it's the same code as an ESC character, * we send a special two character code so as not * to make the receiver think we sent an ESC */ case ESC: send_char(ESC); send_char(ESC_ESC); break; /* otherwise, we just send the character */ default: send_char(*p); } p++; } /* tell the receiver that we're done sending the packet */ send_char(END); } TDC 563 -98 -201/202, Winter 2002 1 -9

IPv 6 (IPng) (1990: IETF starts to work on a new protocol. RFC 1550

IPv 6 (IPng) (1990: IETF starts to work on a new protocol. RFC 1550 - call for proposals for discussion. Listed goals) Goals: 1. Support billions of hosts, even with inefficient address space allocation. 2. Reduce the size of the routing tables. 3. Simplify the protocol, to allow routers to process packets faster. 4. Provide better security than current IP. 5. Pay more attention to type of service, particularly for real-time data. 6. Aid multicasting by allowing scopes to be specified. 7. Make it possible for a host to roam without changing its address. 8. Allow the protocol to evolve in the future. 9. Permit the old and the new protocols to coexist for years. Main Features: · 128 -bit address. · Simplification of header: 7 fields vs 13 in IPv 4. · Better support for options. · Big advance in security: authentication and privacy. · More attention to type of service. TDC 563 -98 -201/202, Winter 2002 1 -10

Figure 25 -1 IPv 6 address Figure 25 -2 Abbreviated address TDC 563 -98

Figure 25 -1 IPv 6 address Figure 25 -2 Abbreviated address TDC 563 -98 -201/202, Winter 2002 1 -11

Figure 25 -3 Abbreviated address with consecutive zeros Figure 25 -4 Partial address FDEF:

Figure 25 -3 Abbreviated address with consecutive zeros Figure 25 -4 Partial address FDEF: : BBFF/96 actually expands into FDEF: 0: 0: 0: BBFF/96 FDEC: 0: 0: BBFF: : /96 or = FDEF: 0: 0: 0 FDEC: : BBFF: 0: 0/96 TDC 563 -98 -201/202, Winter 2002 1 -12

Figure 25 -5 Address Structure TDC 563 -98 -201/202, Winter 2002 1 -13

Figure 25 -5 Address Structure TDC 563 -98 -201/202, Winter 2002 1 -13

Figure 25 -6 Provider-based address Figure 25 -7 Address hierarchy TDC 563 -98 -201/202,

Figure 25 -6 Provider-based address Figure 25 -7 Address hierarchy TDC 563 -98 -201/202, Winter 2002 1 -14

Figure 25 -8 Unspecified address: as a source address only when a host does

Figure 25 -8 Unspecified address: as a source address only when a host does not know its own address Figure 25 -9 Loopback address TDC 563 -98 -201/202, Winter 2002 1 -15

Figure 25 -10 Compatible address: IPv 4 only Figure 25 -11 Mapped address: Migrated

Figure 25 -10 Compatible address: IPv 4 only Figure 25 -11 Mapped address: Migrated to IPv 6 but still want to use IPv 4 TDC 563 -98 -201/202, Winter 2002 1 -16

Local Addresses Figure 25 -12 Link Local Address – like private address not to

Local Addresses Figure 25 -12 Link Local Address – like private address not to be used on the Internet Figure 25 -13 Site local address: private addresses for a network with several subnetworks not connected to the Internet Figure 25 -14 Multicast address TDC 563 -98 -201/202, Winter 2002 1 -17

Figure 25 -15 IPv 6 Datagram Figure 25 -16 IPv 6 datagram format TDC

Figure 25 -15 IPv 6 Datagram Figure 25 -16 IPv 6 datagram format TDC 563 -98 -201/202, Winter 2002 1 -18

Figure 25 -17 Extension Header format TDC 563 -98 -201/202, Winter 2002 1 -19

Figure 25 -17 Extension Header format TDC 563 -98 -201/202, Winter 2002 1 -19

Figure 25 -18 Hop-by-hop option header format TDC 563 -98 -201/202, Winter 2002 1

Figure 25 -18 Hop-by-hop option header format TDC 563 -98 -201/202, Winter 2002 1 -20

The format of options in a hop-by-hop option header Jumbo payload TDC 563 -98

The format of options in a hop-by-hop option header Jumbo payload TDC 563 -98 -201/202, Winter 2002 1 -21

Extension header for routing TDC 563 -98 -201/202, Winter 2002 1 -22

Extension header for routing TDC 563 -98 -201/202, Winter 2002 1 -22

Extension header for routing (source routing) TDC 563 -98 -201/202, Winter 2002 1 -23

Extension header for routing (source routing) TDC 563 -98 -201/202, Winter 2002 1 -23

Fragmentation Header In IPv 6 • minimum MTU = 576 bytes • only source

Fragmentation Header In IPv 6 • minimum MTU = 576 bytes • only source can fragment. Use Path MTU Discovery technique to find the smallest MTU or use 576. Authentication Header • Validate the message sender • Ensures integrity of data (data not altered. • Security parameter index what algorithm to use Encrypted Security Payload (ESP) TDC 563 -98 -201/202, Winter 2002 1 -24

Transport-Mode Encryption e. g. TCP segment or UDP datagram Tunnel-Mode Encryption TDC 563 -98

Transport-Mode Encryption e. g. TCP segment or UDP datagram Tunnel-Mode Encryption TDC 563 -98 -201/202, Winter 2002 1 -25

Transport mode vs tunnel mode (Usually host to host) (Usually between security devices such

Transport mode vs tunnel mode (Usually host to host) (Usually between security devices such as firewalls and gateways) TDC 563 -98 -201/202, Winter 2002 1 -26

Transition from IPv 4 to IPv 6: Strategies Dual-stack operation • An IPv 6

Transition from IPv 4 to IPv 6: Strategies Dual-stack operation • An IPv 6 nodes run both IPv 6 and IPv 4 and use the Version field to decide which stack should process an arriving packet. • Initially all hosts should have a dual stack before migrating completely. TDC 563 -98 -201/202, Winter 2002 1 -27

Header Translation • When a majority of the Internet has migrated to IPv 6

Header Translation • When a majority of the Internet has migrated to IPv 6 TDC 563 -98 -201/202, Winter 2002 1 -28

Tunneling: when IPv 6 packets must travel through an IPv 4 region Tunneling (Configured)

Tunneling: when IPv 6 packets must travel through an IPv 4 region Tunneling (Configured) TDC 563 -98 -201/202, Winter 2002 1 -29

Tunneling (Automatic) TDC 563 -98 -201/202, Winter 2002 1 -30

Tunneling (Automatic) TDC 563 -98 -201/202, Winter 2002 1 -30

Sending rules for an IPv 6/IPv 4 node Key to abbreviations TDC 563 -98

Sending rules for an IPv 6/IPv 4 node Key to abbreviations TDC 563 -98 -201/202, Winter 2002 1 -31