ipv6 al-majrashi, fahad 208192 al-muqairen, fahad 215721
TRANSCRIPT
IPv6AL-MAJRASHI, FAHAD 208192
AL-MUQAIREN, FAHAD 215721
TOPICSTOPICS Why IPv6Why IPv6 How IPv6 DevelopedHow IPv6 Developed Basic functions &Basic functions & Offerings of IPv6 of IPv6 Changes From IPv4 to IPv6Changes From IPv4 to IPv6 Header FormatHeader Format Network AddressingNetwork Addressing Special IPv6 addressesSpecial IPv6 addresses Extension Headers
Why IPv6Why IPv6
IPv6 is the next generation of the Internet Protocol.
It will eventually replace IPv4. The development and the expand in using the
internet created heavy demand for new IP address.
The 32 bits of IPv4 will be exhausted so there will be need for larger one.
75% of IPv4 space allocated to US, only 25% for the rest of the world.
How IPv6 DevelopedHow IPv6 DevelopedThe current version (IPv4) is running out of addresses
and become too complex to manage. It is designed to interoperate with IPv4 because it
need many years for this transition The Internet Engineering Task Force (IETF) began to
solve the problem of exhaustion for IPv4. By 1994, the new version of IPv6 was invented.
Basic functions of IPv6Basic functions of IPv6 It retain the most basic service provided by
IPv4. It is connectionless delivery service. IPv6 has the ability to support the functions do
not work will with IPv4 and the new emerging applications such as
- real-time video conferencing. IPv6 leaps from 32 to 128-bit addressing.
IPv6 OfferingsIncreased address space.Improved efficiency in routing and packet handling.Support for auto configuration and plug and play.Support for embedded IPSec.
Enhanced support for Mobile IP and mobile computing devices.Elimination of the need for network address translation (NAT).Support for widely deployed routing protocols.
Increased number of multicast addresses, and improved support for multicast.
Changes From IPv4 to IPv6 (1/3)Changes From IPv4 to IPv6 (1/3) Longer address field: - Length of IPv4 is 32bits while it is 128 bits for
IPv6.- Provides more level of hierarchy.- It can support up to 3.4 x 10 hosts. Simplified header format:- Some of the headers like checksum and IHL do
not appear in IPv6.
Changes From IPv4 to IPv6 (2/3)Changes From IPv4 to IPv6 (2/3) Flexible Support for Options:- Options in IPv6 appear in optional extension
headers.- More efficient and flexible. Flow label capability:- To identify a certain packet “flow”
Changes From IPv4 to IPv6 (3/3)Changes From IPv4 to IPv6 (3/3) Security: confidentiality. Large Packets: longer than 64K bytes
called “jumbo” payloads. Fragmentation at source only: check the
minimum MTU along the path. No checksum field: to reduce packet
processing time in a router.
IPv6 Value Proposition Engineered to Perform
Uses a 32-bit address
Running out of internet addresses
System management is complex and slow
Incredibly successful
20 + years old
Uses 128-bit addressing
Enough address space to give every human on the planet a unique IP address
Less Infrastructure Maintenance and complexity required
More efficient Mobile IP = seamless service availability
Architecture of the future = Next Generation internet
IPv4 IPv6
Header FormatHeader Format Consist of a required basic header and optional
extension header.
Packets transmitted in network byte order.
The IPV6 address are four times as large as the
IPV4 address.
The header length is only twice as big.
The IPv4 header
0 bits 31
Ver IHL Total Length
Identifier Flags Fragment Offset
32 bit Source Address
32 bit Destination Address
4 8 2416
Service Type
Options and Padding
Header ChecksumProtocol
RemovedChanged
Time to Live
The IPv6 header0 31
Version Class Flow Label
Payload Length Next Header Hop Limit
128 bit Source Address
128 bit Destination Address
4 12 2416
Header Format ( 1/2)Header Format ( 1/2)
The header consist of the following field: Version: at the beginning stays un changed. The traffic class: specifies the priority of the
packet. Flow label: defined as” a sequence of packets
sent to a particular destination. ex: packet video system must delivered within
a certain time constraint. Hosts don’t support this field ( set to 0).
Header Format ( 2/2)Header Format ( 2/2) Payload length: the length of the data.
Next header: identifies the type of the extension header, similar to options in IPv4 that follow the basic header.
Hop limit: the number of hops that packet can travel.
Source and destination address.
Network AddressingNetwork Addressing IPv6 address is 128 bits long. Sufficient for many years. More flexibility in terms of address allocation. It is divided into three categories: Unicast addresses – single network interface. Multicast addresses – group of network
interfaces, at different locations. –packet will be sent to all network interfaces in
the group.
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Network AddressingNetwork Addressing3 Anycast addresses – group of network
interfaces – packet will be sent only to one network interface in the group (nearest one).
The broadcast address supported with a multicast address.
IPv6 uses hexadecimal digits for every for bits and separates every 16 bits with a colon.
3
Network AddressingNetwork Addressing Example of an IPv6:
4BF5:AA12:0216:FEBC:BAF5:039A:BE9A:2176
Often IPv6 can be shortened to more compact form:
1 when the 16-bits field has some leading zeros
4BF5:0000:0000:0000:BAF5:039A:000A:2176
4BF5:0:0:0:BAF5:39A:A:2176
1
Network AddressingNetwork Addressing2 when consecutive zero-valued fields appear 4BF5:0:0:0:BAF5:39A:A:2176
can be shortened by [double colon (::)] 4BF5::BAF5:39A:A:2176
- To recover the original address from one containing a double colon:
you take the non-zero value that appear to the left of the double colons and align them to the left and the number to the right align them to the right
and set zeros between them.
2
Network AddressingNetwork Addressing The dotted-decimal notation of IPv4 can be mixed
with the new hexadecimal notation:
e.g. ::FFFF:128.155.12.198 Less than 30 percent of the address space has been
assigned and the remaining saved for the future. Most types are assigned for unicast addresses. Address allocations are organized by types, which
are in turn classified according to prefixes
( leading bits of the address).
Network AddressingNetwork Addressing Address types based on prefixes Address types based on prefixes
Special IPv6 addressesSpecial IPv6 addresses 1 The address 0::0 is called unspecified address
and is never used as a destination address. It is used as a source address when station wants to learn its address.
2 The address ::1 is used for loopback.
3 IP mapped addresses used to indicateIPv4 hosts and routers that don’t support IPv6. It consists of 80 bits of zeros, followed by 16 bits of 1s, and then by 32 bits of IPv4 address.
1
2
3
Special IPv6 addressesSpecial IPv6 addresses4 IPv4 compatible addresses needed during
the transition period where an IPv6 packet needs to be “tunneled” across an IPv4 network. They are used by IPv6 routers and hosts that directly connected to an IPv4 network. It consists of 96 bits of zeros followed by 32 bits of IPv4 address. Example:
IPv4 address 135.150.10.247
can be converted to an IPv4 compatible IPv6
:: 135.150.10.247
4
Special IPv6 addressesSpecial IPv6 addresses
5 Provider – based unicast addresses are identified by the prefix 010.
It appears that these addresses will be mainly used by the internet service providers to assign addresses to their subscribers.
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Extension Headers
To support extra functionalities that are not provides by the basic header.
IPv6 allows number of extension headers between the basic header and the payload.
Extension headers act like options in IPv4. More efficiently and flexibility. There are six extension headers has been
defined.
Extension Headers
The extension header are daisy chained by the next header field.
The following figure illustrates of the next header field.
A consequence of the daisy-chain formation is that the extension headers must be processed in the order which they appear in the packet.
Extension Headers
Daisy-chain extension headers.
TCP segment
Routing header Next header= fragment
TCP segment
Authentication Header
Next header =TCP
Fragment headerNext header=
Authentication
Basic header Next header=
TCP
Basic header Next header=
TCP
Extension Headers
header code header type
0 hop-by-hop options header
43 Routing header
44 Fragment header
51 Authentication header
52 Encapsulating security payload header
60 Destination options header
Some Uses of Extension Headers
LARGE BACKET
- IPv6 allows a payload size of more than 64K by using an extension header.
- used by super computers. FRAGMENTATION
- fragmentation performed by the source only which make the routers process packets faster.
Some Uses of Extension Headers
SOURCE ROUTING- Allows the source host to specify the sequence
of routers to be visited by a packet to reach the destination.
- It is defined by routing extension header.
Links
IPv6 information:http://ipv6.internet2.edu
90-minute talk about IPv6:http://www.nanog.org/mtg-0306/doyle.html
Recent IPv6 newshttp://www.hs247.com/
Thank You