Network Working Group                                            F. Yang
Internet-Draft                                                  W. Cheng
Intended status: Informational                              China Mobile
Expires: August 23, 2021                                         S. Peng
                                                                   Z. Li
                                                                  Huawei
                                                       February 19, 2021


    Usage scenarios of Application-aware Networking (APN) for SD-WAN
                    draft-yang-apn-sd-wan-usecase-01

Abstract

   This document describes the usage of Application-aware Networking
   (APN) in SD-WAN scenarios.  In these scenarios, APN is able to
   identify a particular application, steer its traffic flows along
   explicit path across the network, and provide SLA guaranteed network
   services such as low latency and high reliability.

Requirements Language

   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 RFC 2119 [RFC2119].

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
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   This Internet-Draft will expire on August 23, 2021.

Copyright Notice

   Copyright (c) 2021 IETF Trust and the persons identified as the
   document authors.  All rights reserved.




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   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
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   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Usage Scenarios of APN for SD-WAN . . . . . . . . . . . . . .   3
     2.1.  APN for Traffic Steering into Dedicated WAN . . . . . . .   3
     2.2.  APN for Traffic Steering into Particular Cloud  . . . . .   3
     2.3.  APN for Value-added Service Provisioning in SD-WAN  . . .   4
     2.4.  APN for Data Processing in SD-WAN . . . . . . . . . . . .   4
   3.  APN with SRv6 . . . . . . . . . . . . . . . . . . . . . . . .   5
   4.  Business Model of APN enhanced SD-WAN . . . . . . . . . . . .   6
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .   6
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   6
   7.  Normative References  . . . . . . . . . . . . . . . . . . . .   6
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   7

1.  Introduction

   As more and more applications are moved to the cloud, the traditional
   WAN architecture starts facing challenges.  Software-defined Wide
   Area Network (SD-WAN) provides a cloud-friendly way of
   interconnecting branch offices and applications in the cloud over any
   combination of transport services such as MPLS and 4G LTE, which is
   able to optimising application performance with low costs.

   Application-aware Networking (APN) is introduced in
   [I-D.li-apn-framework] and [I-D.li-apn-problem-statement-usecases].
   APN conveys application information such as application/user/flow
   identifiers and SLA/service requirements along data packets into
   network [I-D.li-6man-app-aware-ipv6-network] and make the network
   aware of applications and their requirements, so to provide
   corresponding network services and guarantee their SLA requirements.
   The ever-emerging network services such as network slicing and iOAM
   can be further enhanced with the application awareness in the network
   enabled by APN.

   This document describes the usage scenarios of APN for SD-WAN.





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2.  Usage Scenarios of APN for SD-WAN

   This section describes the scenarios that can use APN to meet the
   fine-granularity service operations in SD-WAN.

2.1.  APN for Traffic Steering into Dedicated WAN

   In CPE, different applications can be recognized and their traffic
   flows can be steered into different WANs that can guarantee their
   corresponding SLA requirements.



+------+                        +-----------+                     +------+
| APP1 |                 /------|    WAN1   |------\              | APP1 |
+------+                /       +-----------+       \             +------+
  +------+     +-------+      +-----------+      +--------+     +------+
  | APP2 |-----|  CPE  |------|    WAN2   |------|  CPE   |-----| APP2 |
  +------+     +-------+      +-----------+      +--------+     +------+
+------+                \       +-----------+       /             +------+
| APP3 |                 \------|    WAN3   |------/              | APP3 |
+------+                        +-----------+                     +------+



                         Traffic Steering into WAN

2.2.  APN for Traffic Steering into Particular Cloud

   In the multi-cloud scenario, a CPE can be deployed by an enterprise
   as its gateway to access different clouds.  In the CPE (e.g. an
   universial CPE, called uCPE), different applications can be
   recogonized and steered into the corresponding cloud where the
   application servers are running through the corresponding WANs.

















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   +------+                       +-----------+     +----------+
   | APP1 |             /---------|    WAN1   |-----|  Cloud1  |
   +------+            /          +-----------+     +----------+
     +------+     +--------+     +-----------+     +----------+
     | APP2 |-----|   CPE  |-----|    WAN2   |-----|  Cloud2  |
     +------+     +--------+     +-----------+     +----------+
   +------+            \          +-----------+     +----------+
   | APP3 |             \---------|    WAN3   |-----|  Cloud3  |
   +------+                       +-----------+     +----------+



                        Traffic Steering into Cloud

2.3.  APN for Value-added Service Provisioning in SD-WAN

   APN can faciliate the value-added service provisioning in SD-WAN,
   either at the CPE or the POP.

   At the CPE, network security and application acceleration services
   can be provided.  With APN, certain malicious applications can be
   recogonized and blocked, while the traffic from the applications that
   require acceleration can be steered through the acceleration service.

   At the POP, value-added service can be provisioned for certain
   applications according to the application information carried in
   their packets.


                                +------------+
                                |POP(VAS/SFC)|
                                +------------+
                                       |
  +-----+    +------------+     +------------+     +------------+     +-----+
  | APP |----|CPE(VAS/SFC)|-----|     WAN    |-----|CPE(VAS/SFC)|-----| APP |
  +-----+    +------------+     +------------+     +------------+     +-----+


                             VAS Provisioning

2.4.  APN for Data Processing in SD-WAN

   In enterprise, usually important data is kept locally and it is
   preferred to be processed locally, while other data can be processed
   with the complex processing capabilities in the cloud.






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   With APN, the traffic can be steered according to the localization
   characteristics of the data, either being processed locally or in the
   cloud.




     +------+     +-------+     +------------+     +------------------+
     | Data |-----|  CPE  |-----|    WAN     |-----| Cloud (Computing)|
     +------+     +-------+     +------------+     +------------------+
                       \
                        \    +---------------------------+
                         --- | Local DC (Data Processing)|
                             +---------------------------+


                              Data Processing

3.  APN with SRv6

   By carrying the application identification and demand information
   through data packets, i.e., the delivery of application information
   and ensuring the security and reliability of application information,
   the network senses the application and provides it with high-quality
   differentiated services according to the demand of the application.
   And when the network transmits the data packets, it matches the
   network correspondence policy according to the application
   information in the data packets and selects the corresponding SRv6
   path to transmit the data packets (e.g., low latency path) to meet
   the SLA requirements and service chain in order to improve the
   service quality.



      +------+                 +-----------+                   +------+
      | APP1 |           /-----| SRv6 path1|-----\             | APP1 |
      +------+          /      +-----------+      \            +------+
        +------+   +-------+    +-----------+   +--------+   +------+
        | APP2 |---|  CPE  |----| SRv6 path2|---|  CPE   |---| APP2 |
        +------+   +-------+    +-----------+   +--------+   +------+
      +------+          \      +-----------+      /            +------+
      | APP3 |           \-----| SRv6 path3|-----/             | APP3 |
      +------+                 +-----------+                   +------+


                            SRv6 enabled SD-WAN





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4.  Business Model of APN enhanced SD-WAN

   With the digital transformation, the network infrastructure and
   cloud-based applications are emerging as an integrated service of
   network operators to provide a complete solution to customer.  As an
   overlay technology, SD-WAN is able to simplify the network and make
   it more service-focused, which has become the de facto option for the
   Enterprise WAN Edge.  With SD-WAN, the network is not just a pipe any
   more, and network becomes application aware.  It enables the network
   service providers to reshape their network to provide more complex
   products to meet customers' various requirements.

   When SD-WAN is integrated with APN, service providers are able to
   provide network services together with cloud services in a fine-
   granularity SaaS-like model.  The latest functionalities can be
   delivered via cloud.  Customers benefit from the pay-for-use model in
   per application granularity and have the agility to adjust the level
   of functionality, capability, and capacity.  According to the
   application-aware information carried by the important applications,
   corresponding paths/WANs can be selected, the SLA can be guaranteed,
   and value-added services can be provisioned.

5.  Security Considerations

   The security consideration can refer to [I-D.li-apn-framework] .

6.  IANA Considerations

   There are no IANA considerations in this document.

7.  Normative References

   [I-D.li-6man-app-aware-ipv6-network]
              Li, Z., Peng, S., Li, C., Xie, C., Voyer, D., Li, X., Liu,
              P., Liu, C., and K. Ebisawa, "Application-aware IPv6
              Networking (APN6) Encapsulation", draft-li-6man-app-aware-
              ipv6-network-02 (work in progress), July 2020.

   [I-D.li-apn-framework]
              Li, Z., Peng, S., Voyer, D., Li, C., Geng, L., Cao, C.,
              Ebisawa, K., Previdi, S., and J. Guichard, "Application-
              aware Networking (APN) Framework", draft-li-apn-
              framework-01 (work in progress), September 2020.








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   [I-D.li-apn-problem-statement-usecases]
              Li, Z., Peng, S., Voyer, D., Xie, C., Liu, P., Qin, Z.,
              Ebisawa, K., Previdi, S., and J. Guichard, "Problem
              Statement and Use Cases of Application-aware Networking
              (APN)", draft-li-apn-problem-statement-usecases-01 (work
              in progress), September 2020.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

Authors' Addresses

   Feng Yang
   China Mobile
   Beijing
   China

   Email: yangfeng@chinamobile.com


   Weiqiang Cheng
   China Mobile
   Beijing
   China

   Email: chengweiqiang@chinamobile.com


   Shuping Peng
   Huawei
   Beijing
   China

   Email: pengshuping@huawei.com


   Zhenbin Li
   Huawei
   Beijing
   China

   Email: lizhenbin@huawei.com







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