1 ipv6 advantages may 2001 [email protected] may 2001 [email protected]
TRANSCRIPT
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What is IPv4?What is IPv4?What is IPv4?What is IPv4?
Version 4 of the Internet Protocol 30+ Years Old Incredibly successful
– Today’s Internet runs over IPv4 IPv4 address is 32 bits Many add-ons Showing its age
presentation
session
application
transport
network
link
physical
IPv4
TCP, UDP
Ethernet
Web, ftp,telnet, etc.
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What is IPv6?What is IPv6?What is IPv6?What is IPv6?
Version 6 of the Internet Protocol– Version 5 was allocated to the
experimental Internet Stream Protocol (RFC 1190)
5+ years old Poised for the continued growth
and success of the Internet IPv6 address is 128 bits
presentation
session
application
transport
network
link
physical
IPv6
TCP, UDP
Ethernet
Web, ftp,telnet, etc.
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IPv4: A Victim of Its Own SuccessIPv4: A Victim of Its Own SuccessIPv4: A Victim of Its Own SuccessIPv4: A Victim of Its Own Success
1990 - IPv4 addresses being consumed at an alarming rate, projections show:
Class B address space exhausted by 1994 All IPv4 address space exhausted between 2005 - 2011
– Internet routing tables suffering explosive growth Internet routing today is inefficient
Running out of Internet addresses– Stops Internet growth for existing users
– Prevents use of the Internet for new users
– Forces users to use Private Addresses
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Interim MeasuresInterim MeasuresInterim MeasuresInterim Measures
CIDR (Classless Inter-Domain Routing)– Eased routing table growth
Private addresses– Reduced pressure on address space, but…– Necessitated Network Address Translation, but…
Single point of failure Network performance penalty Breaks applications that rely on end-to-end IP
addressing (FTP, DNS, others)– Use ALGs
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More User Problems with IP todayMore User Problems with IP todayMore User Problems with IP todayMore User Problems with IP today
System administration– Labor intensive, complex, slow, and error prone
– Subscriber networks cannot be dynamically renumbered or configured
Security is optional; no single standard No support for new protocols
– Difficult to add to the base IPv4 technology
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Interim Measures Helped, But …Interim Measures Helped, But …Interim Measures Helped, But …Interim Measures Helped, But …
Address space consumption slowed, but Internet growth accelerated
– “Everything to the Internet” 1B mobile users by 2005 1B Internet users by 2005 90% of all new mobile phones will have internet
access by 2003 (Morgan Stanley Dean Witter, May 2000)
Projections of address space exhaustion by 2010– Pain Sooner (Europe and Asia)
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… … a longer term solution a longer term solution IP next generation (IPng) IP next generation (IPng)… … a longer term solution a longer term solution IP next generation (IPng) IP next generation (IPng)
1991: Work starts on next generation Internet protocols– More than 6 different proposals were developed
1993: IETF forms IPng Directorate– To select the new protocol by consensus
1995: IPv6 selected– Evolutionary (not revolutionary) step from IPv4
1996: 6Bone started 1998: IPv6 standardized Today: Initial products and deployments
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IPv6 Base TechnologyIPv6 Base Technology
WinsWins
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Design PhilosophyDesign PhilosophyDesign PhilosophyDesign Philosophy
Recognizable yet simplified header format Reduce common-case processing cost of packet
handling Keep bandwidth overhead low in spite of
increased size of the address Flexible and extensible support for option
headers Design optimised for 64-bit architecture
– Headers are 64-bit aligned
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128 bit Source Address
128 bit Destination Address
bit 0 31
Version IHL Total Length
Identifier Flags Fragment Offset
32 bit Source Address
32 bit Destination Address
8 2416
Service Type
Options and Padding
Time to Live Header ChecksumProtocol
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Version Class Flow Label
Payload Length Next Header Hop Limit
4 12 2416
IPv6 Header – Comparison with IPv4 IPv6 Header – Comparison with IPv4 IPv6 Header – Comparison with IPv4 IPv6 Header – Comparison with IPv4
IPv4 Header 20 octets, 12 fields, including 3 flag bits + fixed max number of options
IPv4 Header 20 octets, 12 fields, including 3 flag bits + fixed max number of options
IPv6 Header 40 octets, 8 fields+ Unlimited Chained Extension (options) Header
IPv6 Header 40 octets, 8 fields+ Unlimited Chained Extension (options) Header
RemovedChanged
bit 0
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IPv6 Header
Next = TCP
TCP Header Application Data
IPv6 Header
Next = Frag
TCP HeaderFragment Hdr
Next = Security
Security Hdr
Next = TCP
DataFrag
IPv6 Extension HeadersIPv6 Extension HeadersIPv6 Extension HeadersIPv6 Extension Headers
IP options have been moved to a set of optional Extension Headers
Extension Headers are chained together
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IPv6 Header IPv6 Header Performance Wins LayoutPerformance Wins LayoutIPv6 Header IPv6 Header Performance Wins LayoutPerformance Wins Layout
Fixed Size IPv6 Header– Unlike IPv4 - Options not limited at 40 bytes
Fewer fields in basic header – faster processing of basic packets
64 Bit Alignment Header/Options Efficient option processing
– Option fields processed only when present
– Processing of most options limited performed only at destination
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IPv6 Header IPv6 Header Performance Wins Processing Performance Wins Processing
IPv6 Header IPv6 Header Performance Wins Processing Performance Wins Processing
Remove checksum from Network Layer– Datalinks are more reliable these days– Upper Layer checksums are now mandatory (for
example, TCP, UDP, ICMPv6) No fragmentation in the network
– Reduce load on routers– Easier to implement in hardware– Easy for Layer 3 switching of IP
Minimum link MTU is 1280 bytes – From 68 in IPv4
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The power of IPv6The power of IPv6
Addressing
Management
Security
Addressing
Management
Security
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Addressing Model (RFC 2373)Addressing Model (RFC 2373)Addressing Model (RFC 2373)Addressing Model (RFC 2373)
Addresses assigned to interfaces No change from IPv4 model
Interfaces typically have multiple addresses Subnets associated with single link
A link is a link-layer (layer 2) domain e.g. LAN No change from IPv4 model Multiple subnets on same link
IPv6 addresses have scope and lifetime
Link-LocalSite-LocalGlobal
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IPv6 Unicast AddressIPv6 Unicast AddressIPv6 Unicast AddressIPv6 Unicast Address
Address = prefix of n bits + interface ID of 128-n bits Separate “who you are” from “where you are
connected to”
Aggregatable Global Unicast Address format
prefix Interface ID
128-n bitsn bits
Prefix Representation <prefix>::/<n-bits>
3FFE:0301:DEC1:: 0A00:2BFF:FE36:701E
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The power of IPv6The power of IPv6
Addressing
Management
Security
Other IPv6 goodies
Addressing
Management
Security
Other IPv6 goodies
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Network ManagementNetwork ManagementNetwork ManagementNetwork Management
Address Autoconfiguration– Designed for hosts
It is assumed that routers are configured by some other means
– Provides “Plug-and-Play” capability– Defines methods for obtaining routable address(es):
Link Local Address (No router or server required) Stateless mechanism (Router advertisements provide
prefix) Stateful mechanism (Server provides address ( DHCP)
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Network Management Network Management Network Management Network Management
Renumbering IPv6 hosts is easy– Add a new prefix to the router– Reduce the lifetime of the old prefix– As nodes deprecate the old prefix, they begin using the
new prefix for new connections– No network downtime
Renumbering IPv6 routers– New protocol: Router Renumbering (RFC 2894)
An end of ISP “lock in”!– Improved competition
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Mobile IPv6Mobile IPv6Mobile IPv6Mobile IPv6
IPv6 Mobility is based on core features of IPv6– The base IPv6 was designed to support Mobility– Mobility is not an “Add-on” features
IPv6 Neighbor Discovery and Address Autoconfiguration allow hosts to operate in any location without any special support
No single point of failure (Home Agent) More Scalable : Better Performance
– Less traffic through Home Link – Less redirection / re-routing (Traffic Optimisation)
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The power of IPv6The power of IPv6
Addressing
Management
Security
Addressing
Management
Security
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IPv6 Mandates IP SecurityIPv6 Mandates IP SecurityIPv6 Mandates IP SecurityIPv6 Mandates IP Security
Security features are standardized and mandated– All implementations must offer them
Extensions to the IP protocol suite (RFC 2401)– Authentication (Packet signing)– Encryption (Data Confidentiality)
Operates at the IP layer– Invisible to applications
Protects all upper layer protocols Protects both end-to-end and router-to-router
(“secure gateway”)
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SummarySummary
A decade of design and testingA decade of design and testingA decade of design and testingA decade of design and testing
Core IETF specs have reached Draft Standard status
Internet Draft
RFC Proposed Standard
RFCDraft
Standard
RFCInternet
Standard
Technically complete
MultipleInteroperable
Implementations
SignificantOperationalExperience
Yes Yes Yes
No No
timeline
1991
Today6bone test bed
1996 1998
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IPv6 key features and AdvantagesIPv6 key features and AdvantagesIPv6 key features and AdvantagesIPv6 key features and Advantages
Increased Address Space Efficient and extensible IP datagram Improved host and router discovery Plug and Play Enhancements for Quality of Service (QoS) Improved Mobile IP support IPsec mandated Coexistence with IPv4 Extensibility of the Architecture
Available TODAY in commercial products
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ConclusionConclusionConclusionConclusion
IPv6 Solves many of the problems caused by the IPv4 success and more...
The technology you’ve been waiting for is here… Start deploying today!
Imagine what IPv6 can do for you!Imagine what IPv6 can do for you!
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Questions?Questions?Questions?Questions?