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<rfc category="info"
     docName="draft-du-ccwg-framework-of-data-express-service-00"
     ipr="trust200902">
  <front>
    <title abbrev="Framework of DES">A Framework of Data Express
    Service</title>

    <author fullname="Zongpeng Du" initials=" Z." surname="Du">
      <organization>China Mobile</organization>

      <address>
        <postal>
          <street>No.32 XuanWuMen West Street</street>

          <city>Beijing</city>

          <code>100053</code>

          <country>China</country>
        </postal>

        <email>duzongpeng@foxmail.com</email>
      </address>
    </author>

    <date month="" year=""/>

    <area>Internet Area</area>

    <workgroup>CCWG</workgroup>

    <keyword>data express service</keyword>

    <abstract>
      <t>This document describes a potential framework for Data Express
      Service, and related technology requirements.</t>
    </abstract>

    <note title="Requirements Language">
      <t>The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
      "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
      document are to be interpreted as described in <xref
      target="RFC2119">RFC 2119</xref>.</t>
    </note>
  </front>

  <middle>
    <section title="Introduction">
      <t>As rapid development of the AI technologies, we need more powerful
      computing capability. In addition, sharing of the data and computing
      resource would also be necessary. Under this situation, the network
      needs to provide Data Express Service (DES) between different entities.
      The target of the service is normally to transfer a large file or a
      bundle of files, and the size may be at the GB, TB level, or even
      bigger.</t>

      <t>Although we can connect to a cloud service anywhere now, sometimes
      the file upload experience is not satisfying. Alternatively, we can post
      a hard disk to others for this big data transferring. However, if the
      job is repeated, it is surely boring and inconvenient. As the
      requirements of Data Express Service are growing fast, we need to
      provide a more convenient approach.</t>

      <t>The mechanisms in Data Express Service should be more automatic and
      convenient than the current approaches. Comparing to the approach of
      transferring by using the Internet directly, the DES should be quicker
      and automatic. Comparing to the manual hard disk express, the DES should
      be more extensible and convenient.</t>

      <t>In details, the DES scenarios may include inter-cloud backup and
      disaster recovery, film and television editing, scientific computing,
      cooperation of intelligent computing centers.</t>

      <t>This document aims to analyse the requirements of DES, and proposes a
      potential framework for it.</t>
    </section>

    <section anchor="requirement" title="Requirements of DES">
      <t>The demands of the DES traffic would be slightly different from the
      current Internet services.</t>

      <t>The first one is that it may be not that real-time. It is only
      required to be completed within a time limitation. Some may need to be
      completed within hours, and some may need to be completed within one day
      or two days.</t>

      <t>The traffic amount would be huge normally, and the flow would last
      for a while in the network. It would appear as an elephant flow in the
      network.</t>

      <t>Hence, the traffic characteristic of the DES would be more
      predictable than the current Internet service, and we can provide
      specific treatment for these traffic. Even, we can schedule the
      transport time for them, only if we can finish it on-time. In other
      words, we can store the file waiting to be transported.</t>
    </section>

    <section anchor="framework"
             title="Framework of DES and Related Technology">
      <t>A framework for DES is proposed in this section as shown in Figure 1.
      We recognize two network environments in the framework, i.e., the access
      network and the core network.</t>

      <t>Traditionally, the client can connecte to the cloud directly.
      However, due to the complexed E2E network environment, the E2E transport
      speed sometimes is not satisfying.</t>

      <t>For the DES, we can split the E2E connection into three parts: from
      the client to a Data Harbor, among the Data Harbors, and from the Data
      Harbor to the cloud. The Data Harbors can communicate with each other at
      a high speed; meanwhile, it can store the files temporarily.</t>

      <figure>
        <artwork><![CDATA[
   +--------+                +----------+                   +--------+ 
   | client |+               |          |                   |        |+
   +--------+|+   Access     |  Data    |           Access  | Cloud  ||+
    +--------+|        ------| Harbor1  |-------            |        |||
     +--------+      /       |          |        \          +--------+||
                   /         +----------+          \         +--------+|
                 Core                              Core       +--------+
               /                                      \          Access
        +---------+                                      +-------------+
        |         |                                      |             |
        |  Data   |                                      |   Data      |
        | Harbor2 | --------------Core Network---------- |  Harbor3    |
        |         |                                      |             |
        +---------+                                      +-------------+
         Access Network                                   Access Network
          +--------+                                     +--------+    
          | client |+                                    | client |+   
          +--------+|+                                   +--------+|+   
           +--------+|                                    +--------+|  
            +--------+                                     +--------+ 
     
   Figure 1: A framework for Data Express Service with Data Harbors  

]]></artwork>
      </figure>

      <t>As an example, the procedures of the DES service are as follows:</t>

      <t>Step1: a client connects to an available Data Harbor and uploads its
      files, if its speed to the target cloud is not satisfying. Meanwhile,
      the client should provide the time limitation for the files.</t>

      <t>Step2: the Data Harbors should schedule the transport time for the
      files according to its time limitation and the link load between target
      Data Harbors.</t>

      <t>Step3: after receiving the files, the target Data Harbors should
      upload the files to the cloud according to its time limitation and the
      link load between the target Data Harbors and the cloud.</t>

      <t>If we have many clients that need the DES services, we can built a
      high speed link between specific Data Harbors. This is the key feature
      that the DES can be more quick than a normal Internet connection. Under
      this situation, we also need a high speed transport protocol to
      transport files efficiently, or more specifically, a specific designed
      congestion control method for the Data Harbors. The methods mentioned in
      <xref target="I-D.ietf-ccwg-rfc5033bis"/> can be considered here.
      Optionally, to improve the speed between the Data Harbors, we can also
      deploy RDMA mechanisms.</t>
    </section>

    <section anchor="IANA" title="IANA Considerations">
      <t>TBD.</t>
    </section>

    <section anchor="Security" title="Security Considerations">
      <t>TBD.</t>
    </section>

    <section anchor="Acknowledgements" title="Acknowledgements">
      <t>TBD.</t>
    </section>
  </middle>

  <back>
    <references title="Normative References">
      <?rfc include="reference.RFC.2119"?>
    </references>

    <references title="Informative References">
      <?rfc include="reference.I-D.ietf-ccwg-rfc5033bis"?>
    </references>
  </back>
</rfc>
