I. Overview
IPv6 can meet the growing demand for complex systemicized addressing, from IPv4 addressing to IPv6 addressing, Cisco IOS starts support IPv6 from 12.2 (t).
II. IPv6
1. Provide greater address space to enable PLUG AND PLAY and flexible rendering
2. Pleble header information, enabling the router to provide more efficient routing forwarding.
3. Keep compatibility with Mobile IP and IP SEC, Mobility and Security
4. Provides a wide range of methods from IPv4 to IPv6, IPSec is mandatory in IPv6.
Three IPv6 Address
Address space
Address length 128bits or 16bytes
Distributed number of addresses: 38 times of 3.4x10
The number of addresses that each earth can have: 28 times of 5x10
2. IPv6 address format
32 16-piece number, every 4, a total of 8 segments, the segment and segments are separated by ':'
The preamble 0 in each segment can not be written
In the same address, several consecutive segments can be abbreviated as '::'
IPv6 address example:
2031: 0000: 130F: 0000: 0000: 09C0: 876A: 130B correct
2031: 0: 130F: 0: 0: 09c0: 876A: 130B correct
2031: 0000: 130f :: 09c0: 876a: 130b correct
2031 :: 130f :: 09c0: 876a: 130b Error
0: 0: 0: 0: 0: 0: 0: 1 = :: 1 correct
0: 0: 0: 0: 0: 0: 0: 0 = :: Correct
MultiCast, four IPv6
1. IPv6 does not use Broadcast communication, use multicast or Anycast to replace Broadcast
2. MulticSt makes the network more efficient, IPv6 has a very large multicast address space
3. Introduction to AnnaSt:
Multiple routers share the same Unicast address (a set of multicast forwarding routers)
All multicast sources send packets to the Unicast address
The router automatically selects the nearest multicast forwarding router to reach the purpose.
5 IPv6 address aggregation
Multiple address prefixers can be summarized as an address prefix
Address aggregation can increase routing efficiency and expansion capabilities
Six IPv6 address automatic configuration features
Ability to address using the Data-Link address
Ability to automatically configure conflictable address
Plug and play (the host, and the request and notification of the address prefix) between the host and the router)
Seven IPv6 address update
Notify a new prefix by modifying the living time of the old prefix of the router advertisement.
If you change the prefix of the entire network, you may need to change DNS
Eight IPv6 frame format
1. Simplified more efficient header information
64bit headfield, fewer fields
Can realize hardware-based, efficient processing
Improve the efficiency, performance and forwarding rate of routing
2. Comparison of IPv4 and IPv6 information
IPv4 generally uses 12 headers, 20bytes; IPv6 uses 8 headers, 40Bytes, where there are three fields with IPv4, with 3 new fields.
IPv6 does not perform fragmentation operations, so there is no Fragmentation information of IPv4, IPv6 uses a discovery process to determine and adjust the most suitable MTU of a session.
IPv6's sender's discovery handler will automatically adjust the size of the MTU based on the ICMP message returned by the network.
There is no header field in IPv6's header information, depending on the reliability of data transmission with the upper and Data Link layers.
3.IPv6 head format
Version field: 4BITS
Traffic class field: 8bits, TOS similar to IPv4
Flow Label field: 20bits, new 20BITS fields, with multi-layer exchange and fast exchange
PayLoad Length field: 16bits, Total Length field similar to IPv4
Next Header field: 8bits, similar to the IPv4 Protocol field, used to identify the upper level information type of IPv6.
HOP LIMIT field: 8bits, similar to the TTL field of IPv4,
Source Address field: 128bits
Destination Address: 128BITS
4. IPv6 Extension Head Information IPv6 can have many types of extension headers, and can use multiple expanded headers at the same time, the order of applications is as follows:
1) IPv6 Header
2) Hop-by-hop Options Header
3) Destination Options Header
4) Routing Header
5) Fragment Header
6) Authentication Header
7) ENCAPSULATING Security PayLoad Header
8) Destination Options Header
9) Upper-layer header
Interoperability of nine IPv6 and IPv4
1. Overview
There is a rich conversion method from IPv4 to IPv6
Smooth conversion using Dual Stack or 6to4 tunnel
Use NAT to enable IPv4 and IPv6 nodes to communicate
2.ios Dual Stack
Dual Stacked: If IPv4 and IPv6 are configured on an interface, the interface is called Dual Stacked.
Cisco Router needs to use global commands: IPv6 Unicast Routing Enables IPv6
Assign IPv6 address using the interface command: IPv6 Address
3.overLay Tunnel (Covered Tunnel)
Connect two IPv6 networks through an IPv4 backbone network
Pack the IPv6 packet in IPv4 packet transmission method
Dual-Stack interface needs to be used at both ends of the tunnel
The two ends of the tunnel need to configure IPv4 and IPv6 addresses.
4. Use 6to4 tunnel to connect to IPv6 networks
Use IPv4 network connection and transfer IPv6 packets
It is a method of automatically establishing a tunnel.
The two ends of the tunnel need to use a fixed IPv6 prefix (2002 2 byte local border router's IPv4 address)
IPv4 addresses containing the destination boundary router in the destination boundary router
The local boundary router automatically takes out the IPv4 address of this destination, and encapsulates the IPv6 package in the IPv4 package.
The destination boundary router will unpack the received IPv4 packet and forward it to the destination IPv6 host.
Ten, IPv6 route agreement and iOS requirements
Integrated ISIS for IPv6 12.0 (22) S AND 12.2 (8) T
BGP for IPv6 12.0 (22) S AND 12.2 (2) T
Rip for IPv6 12.0 (22) S AND 12.2 (2) T
Static Route for IPv6 12.0 (22) S AND 12.2 (2) T
At present, IPv4 and IPv6 routing protocols are not supported.
