IPv6 Trainnig by 7B4G21r

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									            IPv6 Introduction
•   What is IPv6
•   Purpose of IPv6 (Why we need it)
•   IPv6 Addressing Architecture
•   IPv6 Header
•   ICMP v6
•   Neighbor Discovery (ND)
•   Reference Site
               What is IPv6
•   IP version 6 (Now is IP version 4)
•   IPng (IP The Next Generation)
•   RFC791
•   IPv4 header  IPv6 header
•   IPv4 structure  IPv6 structure
•   Plug and Play
IPv6 address allocation in Asia




         資料來源:http://www.ipv6.org.tw/
IPv6 subnets in Taiwan




    資料來源:http://www.ipv6.org.tw/
            Purpose of IPv6
• IPv4 address bottleneck
    • CIDR (Classless Inter-Domain Routing)
    • NAT (Network Address Translation)
    • 3G and IA (Information Appliance)
• Network Security
    • IPsec (IP security)
• Wireless Mobile Issue
    • Triangle Issue
      Purpose of IPv6 (cont.)
• Running out of address in IPv4
  – 32-bit vs. 128-bit
  – 75% IP addresses in America
  – 3G & IA production
• Multicast function is not useful
• Checksum in 2 Layers
• CIDR is the default usage (without
  netmask)
        Purpose of IPv6 (cont.)
•   Simply the complex Header
•   Reduce router’s loading
•   Extension Header
•   More Security with IPsec
•   QoS (Quality of Service)
•   Auto-Configuration
    – Statefull   (DHCPv6)
    – Stateless   (RS,RA)
 IPv6 Feature (cont.)

                Neighbor Cache
Routing Table

                Destination Cache



                    Prefix List
 ARP Table

                Default Router List




   IPv4               IPv6
  IPv6 Addressing Architecture
• IPv6 Address Rule
    • Unicast Address         (RFC2374)
       – Link local address
       – Site local address
       – Global address
    • Anycast Address         (RFC2526)
    • Multicast Address       (RFC2375)


           No Broadcast Here!!!!!!
           IPv6 Address Rule
• The preferred form is x:x:x:x:x:x:x:x
     • X is 16 bit value
• Long strings of zero bits
     • 0:0:0:0:0:0:0:1      ::1
• “前導0” could be skipped
     • FFEE:BBBB:00A0:0:0:0:0:1  FFEE:BBBB:A0::1
• The "::" can only appear once in an
  address
    Unicast Address-Link local



• Link local address
  – Used on a single link
  – Prefix is 1111 1110 10
  – FE80:
• Usage Timing
  – Automatic Address Configuration
  – Neighbor Discovery
    Unicast Address-Site local




• Site local address
  – Used on a single site
  – Prefix is 1111 1110 11
  – FEC0:
      Unicast Address-Global




• Global address
  – Unique in Internet
  – Prefix is 001
            Anycast Address




• When a unicast address is assigned to more
  than one interface, thus turning it into an anycast
  address, the nodes to which the address is
  assigned must be explicitly configured to know
  that it is an anycast address.
       Anycast Usage


                 R1




                      R2

A                           B

    Lower Cost
                      R3



             Anycast Area
                Multicast Address


• flags         000T (focus on T value)
   – 0 permanently-assigned (well-known address)
   – 1 non-permanently-assigned (transient)
• scope
   –   1:node-local scope
   –   2:link-local scope
   –   5:site-local scope
   –   8:organization-local scope
   –   Others:reserved

       Ex:ff02::1     (link-local) all nodes multicast address
                  Interface ID
• Created from MAC address
• EUI-64 Address
  –   Example for link-local:
  –   MAC addr: 00-01-23-AA-BB-CC
  –   EUI-64:
  –   00-01-23 AA-BB-CC
  –   00-01-23 FF-FE AA-BB-CC
  –   00-01-23 -FF-FE-AA-BB-CC
  –   FE80::1:23FF:FEAA:BBCC/64 <- link-local addr.
        IPv6-IPv4 comparison
IPv4                 IPv6
• Unspecified Host   • Unspecified Host
  – 0.0.0.0            – 0:0:0:0:0:0:0:0 (::)
• Loopback           • Loopback
  – 127.X.X.X          – ::1
• Broadcast          • Multicast
  – 192.168.0.255      – FF02::1
• Netmask            • Netmask
  – 255.255.255.0      – Prefix Number
IPv6 Header
IPv4 Header
IPv6 Extension Headers
Routing Header
          Routing Header
• Created only when use PATH MTU
  function
• PATH MTU:Trying to find out the biggest
  MTU size. (RFC 1981)
Fragment Header
Fragment Procedure



                 All Data
                 ICMP v6
• Internet Control Message Protocol
• RFC 2463
    ICMP sample




       A Ping B
A                 B
       ICMP v4 vs. ICMP v6
• ICMP v4           • ICMP v6
  – echo message      – echo request
    • Type 8            message
  – reply message       • Type 128
    • Type 0          – echo reply
  – code 0              message
                        • Type 129
                      – Code 0
    Neighbor Discovery (ND)
• RFC2461
• Corresponds to a combination of IPv4
  – ARP
  – ICMP Router Discovery
  – ICMP Redirect
        Neighbor Discovery
• 5 messages
  – Neighbor Solicitation (NS)
  – Neighbor Advertisement (NA)
  – Router Solicitation (RS)
  – Router Advertisement (RA)
  – Redirect
• All these messages should fill 255 in hop
  limit field
• Link Layer address
RS (Type 134)
RA (Type 133)
         Regular RA (Type 133)




Use multicast to send its prefix to link-local scope all-nodes
NS (Type 135)
NA (Type 136)
           Reference Site
• www.ipv6.org.tw
• www.ietf.org

								
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