Internet Engineering Task Force N. Kuhn, Ed. Internet-Draft CNES Intended status: Informational E. Lochin, Ed. Expires: May 3, 2018 ISAE H. Skinnemoen AnsuR Technologies S. Ghanem Independent Senior Researcher J. Bilbao G. Peralta Ikerlan October 30, 2017 Network coding and satellites draft-kuhn-nwcrg-network-coding-satellites-01 Abstract This memo presents the current deployment of network coding in some satellite telecommunications systems along with a discussion on the multiple opportunities to introduce these technics at a wider scale. 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 Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on May 3, 2018. Copyright Notice Copyright (c) 2017 IETF Trust and the persons identified as the document authors. All rights reserved. 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 Kuhn, et al. Expires May 3, 2018 [Page 1] Internet-Draft Network coding and satellites October 2017 publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must 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 1.1. Glossary . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Requirements Language . . . . . . . . . . . . . . . . . . 3 2. A note on satellite topology . . . . . . . . . . . . . . . . 3 3. Status of network coding in actually deployed satellite systems . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4. Opportunities for more network coding in satellite systems . 5 5. Deployability and related use cases . . . . . . . . . . . . . 6 5.1. Network coding and VNF . . . . . . . . . . . . . . . . . 6 5.2. Network coding and PEP . . . . . . . . . . . . . . . . . 6 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 6 7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 6 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 9. Security Considerations . . . . . . . . . . . . . . . . . . . 7 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 7 10.1. Normative References . . . . . . . . . . . . . . . . . . 7 10.2. Informative References . . . . . . . . . . . . . . . . . 7 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7 1. Introduction Network coding schemes are inherent part of the satellite systems, since the challenging physical layer require specific robustness to guarantee an efficient usage of the expensive radio resource. Further exploiting these schemes is an opportunity for a better end user experience along with a better exploitation of the scarce resource. In this context, this memo aims at: o summing up the current deployment of network coding schemes; o identifying opportunities for further usage of network coding in satellite systems. Kuhn, et al. Expires May 3, 2018 [Page 2] Internet-Draft Network coding and satellites October 2017 1.1. Glossary The glossary of this memo is related to the network coding taxonomy document [I-D.irtf-nwcrg-network-coding-taxonomy]. The glossary is extended as follows: o XX: XX 1.2. 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]. 2. A note on satellite topology The objective of this section of to provide a generic description of the components composing a generic satellite system and their interaction. It provides a high level description of a multi-gateway satellite network. Figure 1 shows a example of a multigateway satellite system. It is worth pointing out that some functionnal blocks aggregate the traffic coming from multiple users, and thus are opportunity for including network coding. Kuhn, et al. Expires May 3, 2018 [Page 3] Internet-Draft Network coding and satellites October 2017 +---------------------+ | Application servers | +---------------------+ | | | | | | ----------------------------------- v v v v v v +------------------+ +------------------+ | network function | | network function | | (firewall, PEP) | | (firewall, PEP) | +------------------+ +------------------+ | | | | | | IP packets | | v v v v +------------------+ +------------------+ | access gateway | | access gateway | +------------------+ +------------------+ | | | BBFrames | v v +------------------+ +------------------+ | physical gateway | | physical gateway | +------------------+ +------------------+ | | | PLFrames | v v +------------------+ +------------------+ | outdoor unit | | outdoor unit | +------------------+ +------------------+ | | | | | | Satellite link | | v v v v +------------------+ +------------------+ | terminals | | terminals | +------------------+ +------------------+ Figure 1: Data plane functions in a generic satellite multi-gateway system 3. Status of network coding in actually deployed satellite systems Figure 2 presents the status of the network coding deployment in satellite systems. The information is based on the taxonomy document [I-D.irtf-nwcrg-network-coding-taxonomy] and the notations are the following: End-to-End Coding (E2E), Network Coding (NC), Intra-Flow Coding (IntraF), Inter-Flow Coding (InterF), Single-Path Coding (SP) and Multi-Path Coding (MP). Kuhn, et al. Expires May 3, 2018 [Page 4] Internet-Draft Network coding and satellites October 2017 X1 embodies the source coding that could be used at application level for video streaming on a broadband access. X2 embodies the physical layer that is applied on the PLFRAME to have an optimal usage of the satellite capacity. +------+-------+---------+---------------+-------+ | | Upper | Middle | Communication layers | | | Appl. | ware | | + +-------+---------+---------------+-------+ | |Source | Network | Packetization | PHY | | |coding | AL-FEC | UDP/IP | layer | +------+-------+---------+---------------+-------+ |E2E | X1 | | | | |NC | | | | | |IntraF| X1 | | | | |InterF| | | | X2 | |SP | X1 | | | X2 | |MP | | | | | +------+-------+---------+---------------+-------+ Figure 2: Network coding and satellite systems 4. Opportunities for more network coding in satellite systems This section extends Section 3 by presenting the opportunities for more network coding in satellite systems. These opportunities are further detailed in Section 5 and listed in this section: o (1) two way relay channel mode; o (2) reliable multicast; o (3) improving random access; o (4) network coding and hybrid access; We propose to include some of the identified opportunities in the Figure 3. Kuhn, et al. Expires May 3, 2018 [Page 5] Internet-Draft Network coding and satellites October 2017 +------+-------+---------+---------------+-------+ | | Upper | Middle | Communication layers | | | Appl. | ware | | + +-------+---------+---------------+-------+ | |Source | Network | Packetization | PHY | | |coding | AL-FEC | UDP/IP | layer | +------+-------+---------+---------------+-------+ |E2E |X1 | | (4) | | |NC | |(1) |(1)(2)(3)(4) | | |IntraF|X1 | | (2) (4) | | |InterF| |(1) |(1) (3) |X2 | |SP |X1 |(1) |(1) (3) |X2 | |MP | | | (2) | | +------+-------+---------+---------------+-------+ Figure 3: Opportunites for more network coding and satellite systems Opportunities for more network coding in SATCOM seems to be more relevant at the middle ware or at the communication layer levels. 5. Deployability and related use cases This section details use-cases where the usage of network coding schemes could improve the overall system and the deployability of the opportunities that are provided in Section 4. 5.1. Network coding and VNF Related to the foreseen virtualized network infrastructure, the network coding schemes could be proposed as VNF and their deployability enhanced. 5.2. Network coding and PEP Related to the impact and integration of network coding in Proxy- Enhanced-Proxy RFC 3135 [RFC3135] architecture. In particular how network coding can be integrated inside a PEP with QoS scheduler as defined, for instance, in RFC 5865 [RFC5865]. 6. Acknowledgements 7. Contributors Many thanks to Kuhn, et al. Expires May 3, 2018 [Page 6] Internet-Draft Network coding and satellites October 2017 8. IANA Considerations This memo includes no request to IANA. 9. Security Considerations This document, by itself, presents no new privacy nor security issues. 10. References 10.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC3135] Border, J., Kojo, M., Griner, J., Montenegro, G., and Z. Shelby, "Performance Enhancing Proxies Intended to Mitigate Link-Related Degradations", RFC 3135, DOI 10.17487/RFC3135, June 2001, . [RFC5865] Baker, F., Polk, J., and M. Dolly, "A Differentiated Services Code Point (DSCP) for Capacity-Admitted Traffic", RFC 5865, DOI 10.17487/RFC5865, May 2010, . 10.2. Informative References [I-D.irtf-nwcrg-network-coding-taxonomy] Adamson, B., Adjih, C., Bilbao, J., Firoiu, V., Fitzek, F., samah.ghanem@gmail.com, s., Lochin, E., Masucci, A., Montpetit, M., Pedersen, M., Peralta, G., Roca, V., Saxena, P., and S. Sivakumar, "Network Coding Taxonomy", draft-irtf-nwcrg-network-coding-taxonomy-05 (work in progress), July 2017. Authors' Addresses Kuhn, et al. Expires May 3, 2018 [Page 7] Internet-Draft Network coding and satellites October 2017 Nicolas Kuhn (editor) CNES 18 Avenue Edouard Belin Toulouse 31400 France Phone: 0033561273213 Email: nicolas.kuhn@cnes.fr Emmanuel Lochin (editor) ISAE 10 Avenue Edouard Belin Toulouse 31400 France Email: emmanuel.lochin@isae.fr Harald Skinnemoen AnsuR Technologies Martin Linges Vei 25 Fornebu 1364 Norway Email: harald@ansur.no Samah A. M. Ghanem Independent Senior Researcher West Bank Palestine Email: samah.ghanem@gmail.com Josu Bilbao Ikerlan Spain Email: JBilbao@ikerlan.es Goiuri Peralta Ikerlan Spain Email: gperalta@ikerlan.es Kuhn, et al. Expires May 3, 2018 [Page 8]