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Problems in China Telecom (PowerPoint)


									           Problem Statement of
                 China Telecom
                     Guoliang YANG

  Problems and Challenges for
  China Telecom
1. Address Pool Exhaustion                                   2. Protocol Incompatibility
         Predicted extinction date                                           Different protocol Packet format
            Worldwide      2010.10                                            Different treatment for software
               Asia         2012.8
          China Telecom     2013.3

         CT status quo ( Unit: million )       1            2
                                            Motivation   Technology
            Total Space       91

          Exhausting speed 17per yr

  4. Lack of transition experience                                                 3. Inactive Industry Chain
   Giant network scope and large           Deployment                                           Government
  numbers of service platforms need                                                  ICP    Network     Customer
  Considerable human and material

   No practical criteria referenced                              No clear guidelines from government
  for IPv6 transition                                             No drivers for ICP
                                                                  Users do not care
  For network management, product development                    Long Life cycle of ROI
  and service flow, no mature experiences and                      (ROI, Return on Investment)
  examples can be learned from.
     application         IPv4 Contents Transition

                         Transition Technology Selection
                             Problems in deploying Dual Stack
                               NAT444 authentication
            network            User tracing

                               Impact on internet application

                             Problems in deploying tunnels
                               incapable multicast service in Ds-lite

                             Problems in deploying protocol translation
                               Infeasible fixed range port in DIVI

                                 Address planning strategy

 2011/4/9    users       Unavailable PPPoEv6 in Windows XP
Transition Technology Selection
    Considerations which need to be made when applying
     various transition technologies to existing networks.
     Various transition technologies may have different
     impacts to the services:

          Dual Stack with Carrier Grade NAT444
          Tunnel technologies
          Protocol Translation

Problems in deploying Dual Stack
Carrier Grade NAT444: Authentication

    Single-Sign-On of the website:
          The user’s IPv4 private address is allocated by BRAS after AAA process, so, only
           user's private ipv4 address is mapped with the user account in AAA system. In
           some cases, website may make SSO authentication with user’s IP address via
           carrier’s AAA server.
          User accesses the Internet website with public address, while the address in the
           carrier’s AAA Server is private address. So the user can not be authorized.
    VPN authentication
          In L2TP and NAT444 environments with user creating VPN itself, if the user
           wants to access the enterprise internal network via VPN, some authentication
           protocol such as EAP, may not be supported in these two environments.
          AAA authentication
          In some cases, dual stack users may establish dial-up sessions to BRAS to get
           IPv4 and IPv6 address separately.
          BRAS may probably send different radius authentication request packets to AAA.
           According to current anti-attack policies in AAA server, the AAA server will deal
           with the first request packet and ignore the other ones.
Problems in deploying Dual Stack
Carrier Grade NAT444: User tracing

    Flow Analysis System and Behavior Analysis System

          The existing Flow Analysis and Behavior Analysis System of Carrier is centralized
           and deployed in backbone. In NAT444 environment, they both need to be placed
           before NAT device, in order to collect users’ data and analysis their behavior
           accurately by their IPv4 address.

Problems in deploying Dual Stack
Carrier Grade NAT444: Others

    Internet user access the private network users
     initiatively. Currently two access methods are
     considered in the metropolitan area network:
       Communication between Private IP host, the traffic will
        not go through NAT444 device.
      Communication between Private IP host and Public one,
        the traffic will go through NAT444 device.
     For the user who wants to visit a website which is provided
     by private address host, it is not accessible.

    NAT444 doesn’t support the current PPTP VPN.
    Problems in deploying tunnel

     What is the sequence of deployment for tunnel
          6RD、DS-lite and L2TP, etc
          6RDDS-lite or directly to DS-lite?

          Incapable multicast service in DS-Lite:
          For China Telecom, the IPTV multicast replication point is located in BRAS.
           There is a trend to move down the replication point to access node.
          In the DS-Lite scenario, the IPTV multicast replication point will be at AFTR
           which will lead some performance problems and conflict with the above

     What is the investment benefit and maintenance cost of
      different tunnel technology?
Problems in deploying protocol translation

          Infeasible fixed range port in DIVI
              DIVI assigns a fixed range of ports to the HG, for
               users sake, it is infeasible and unfair for customers.

          Much larger traffic will pass the DIVI gateway
           than other technology

Address Planning Strategy
    When IPv6 is deployed, how to plan the IP
     address pool in a large scale network is a

IPv4 Contents Transition
    Lacking business driven and technology driven for IPv4
     Internet contents Providers (ICP) to provide IPv6
     contents. For example, the lifecycle of online games is
     short and deploying IPv6 has long lifecycle of ROI.
     (Return on Investment)

    ICPs need carriers’ guidelines or solutions about the
     IPv4 contents transition.

    How ICP can provide IPv6 services with the least
           Thank you


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