Application-Layer Traffic Optimization C. Xie Internet-Draft W. Wang Intended status: Informational China Telecom Expires: December 26, 2021 Q. Ma Huawei June 24, 2021 ALTO for Querying LMAP Results draft-xie-alto-lmap-00 Abstract Measuring broadband performance on a large scale is important for network diagnostics by providers and users, as well as for public policy. The Large-scale Measurement of Broadband Performance (LMAP) framework, information model, and protocol have been developed for measurement task dissemination, initialization, reporting and storing. In the context of Large-Scale Measurement of Broadband Performance (LMAP), measurement results are currently made available in the repository to the public either at the finest granularity level (e.g. as a list of results of all individual tests), or in a very high level human- readable format. This document uses ALTO protocol to provide access to large-scale network measurement results, flexible enough to enable querying of specific and possibly aggregated data. 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 December 26, 2021. Xie, et al. Expires December 26, 2021 [Page 1] Internet-Draft ALTO for LMAP June 2021 Copyright Notice Copyright (c) 2021 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 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 2. Requirements Language . . . . . . . . . . . . . . . . . . . . 3 3. Example Use Cases . . . . . . . . . . . . . . . . . . . . . . 3 4. Solution Overview . . . . . . . . . . . . . . . . . . . . . . 4 5. Advantages of using ALTO . . . . . . . . . . . . . . . . . . 5 6. Proposed ALTO protocol extension . . . . . . . . . . . . . . 6 7. Security Considerations . . . . . . . . . . . . . . . . . . . 7 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 7 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 10. Normative References . . . . . . . . . . . . . . . . . . . . 7 Appendix A. Example LMAP Report . . . . . . . . . . . . . . . . 7 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10 1. Introduction Measuring broadband performance on a large scale is important for network diagnostics by providers and users, as well as for public policy. The Large-scale Measurement of Broadband Performance (LMAP) protocol [RFC7594] have been developed to gather measurement data and to upload such data to dedicated servers. Apart from protocols that can be used to gather measurement data and to upload such data to dedicated servers, there is also a need for protocols to retrieve - potentially aggregated - measurement results for a certain network (or part of a network), possibly in an automated way. Currently, two extremes are being used to provide access to large- scale measurement results: One the one hand, highly aggregated results for certain networks may be made available in the form of PDFs of figures. Such presentations may be suitable for certain use Xie, et al. Expires December 26, 2021 [Page 2] Internet-Draft ALTO for LMAP June 2021 cases, but certainly do not allow a user (or entity such as a service provider) select specific criteria and then create corresponding results. On the other hand, complete and detailed results may be made available in the form of comma-separated-values(csv) files. Such data sets typically include the complete results being measured on a very fine-grained level and usually imply large file sizes (of result data sets). Such detailed result data sets are very useful e.g. for the scientific community because they enable to execute complex data analytics algorithms or queries to analyse results. Considering the two extremes discussed above, this document uses ALTO protocol to provide access to large-scale network measurement results. It must be possible to query for specific, possibly aggregated, results in a flexible way. Otherwise, entities interested in measurement results either cannot select what kind of result aggregation they desire, or must always fetch large amounts of detailed results and process these huge datasets themselves. The need for a flexible mechanism to query for dedicated, partial results becomes evident when considering use cases where a service provider or a process wants to use certain measurement results in an automated fashion. For instance, consider a video streaming service provider which wants to know for a given end-user request the average download speed by the end user's access provider in the end user's region (e.g. to optimize/parametrize its http adaptive streaming service). Or consider a website which is interested in retrieving average connectivity speeds for users depending on access provider, region, or type of contract (e.g. to be able to adapt web content on a per- request basis according to such statistics). 2. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119][RFC8174] when, and only when, they appear in all capitals, as shown here. 3. Example Use Cases To motivate the usefulness of ALTO for querying LMAP results, consider some key use cases defined in [RFC7536]: o Broadband network maintenance and monitoring A network operator needs to understand the performance of their networks, the performance of the suppliers (downstream and upstream networks), the performance of Internet access services, and the impact that such performance has on the experience of their customers. Largely, the processes that ISPs operate (which Xie, et al. Expires December 26, 2021 [Page 3] Internet-Draft ALTO for LMAP June 2021 are based on network measurement) include Identifying, isolating, and fixing problems, Design and planning,Understanding the quality experienced by customers, Understanding the impact and operation of new devices and technology o Broadband performance benchmarking A regulator may want to evaluate the performance of the Internet access services offered by operators. While each jurisdiction responds to distinct consumer, industry, and regulatory concerns, much commonality exists in the need to produce datasets that can be used to compare multiple Internet access service providers, diverse technical solutions, geographic and regional distributions, and marketed and provisioned levels and combinations of broadband Internet access services. Regulators may want to publish performance measures of different ISPs as background information for end users. They may also want to track the growth of high-speed broadband deployment, or to monitor the traffic management practices of Internet providers. 4. Solution Overview This document addresses how to retrieve potentially aggregated network performance measurement results for a certain network. These network performance measurement results are measured and gathered using LMAP based measurement system. LMAP based measurement system are comprised of three components: Measurement Agent (MA),Collector and Controller. The MA is located in both ingress node and egress node and instructed by the Controller to monitor a particular traffic flowing toward a given destination and to send the Report to the Collector.The Report contains: o the MA-ID or a Group-ID o the actual Measurement Results, including the time they were measured. o the details of the Measurement Task o the Cycle-ID, if one was included in the Instruction. o perhaps the Subscriber's service parameters o the measurement point designation of the MA and, if applicable, the MP or other MA, if the information was included in the Instruction. Xie, et al. Expires December 26, 2021 [Page 4] Internet-Draft ALTO for LMAP June 2021 The collector then provides results to the repository in the ALTO server and format as ALTO information and expose it to the ALTO client, see figure 1. +---------------+ | | +--------+ +----------+ | ALTO Server | | | |Controller| | +----------+ |<--------> ALTO | +------+---+ | |Collector | | | Client | | | | +------^---+ | | | | | +--------+------+ +--------+ | | | | +-------------+ | | | | | | | +----V------+ +--V---+----+ | Ingress | | Egress | | Node | | Node | | +--+ | | +--+ | | |MA| | | |MA| | | +--+ | | +--+ | +-----------+ +-----------+ 5. Advantages of using ALTO The ALTO protocol [RFC7285] specifies a very lightweight JSON-based encoding for network information and can play an important role in querying the measurement results as we argue in Section 2. ALTO is designed on two abstractions that are useful here. First is the abstraction of the physical network topology into an aggregated but logical topology. In this abstract topological view, referred to as "network map", individual hosts are aggregated into a well defined network location identifier called a PID. Hosts could be aggregated into the PID depending on certain identifying characteristics such as geographical location, serving ISP, network mask, nominal access speed, or any mix of them. The "network map" abstraction is essential for exporting network information in a scalable and privacy-preserving way. The second abstraction that is useful for LMAP is the notion of a "cost map". Each PID identified in the network map can, in a sense, become a vertex in a cost map, and each edge joining adjacent vertices can have an associated cost. The cost can be defined by the measurement server and can indicate routing hops, the financial cost of sending data over the link, available bandwidth on the link with bottled-up links increasingly showing a smaller value, or a user- defined cost attribute that allows arbitrary reasoning. Xie, et al. Expires December 26, 2021 [Page 5] Internet-Draft ALTO for LMAP June 2021 The ALTO protocol defines several basic services based on such abstractions, but additional ones can be easily defined as extensions. There are other advantages to using ALTO as well. The protocol is defined as a set of REST APIs on top of HTTP. The data carried by the protocol is encoded as JSON. Queries can be performed by clients locally after downloading the entire topological and cost maps or clients can send filtered requests to the ALTO server such that the ALTO server performs the required computation and returns the results. The protocol supports a set of atomic constraints related to equality that can be used to filter results and only obtain a set of interest to the query. Additionally, protocol extensions that could also be useful for the LMAP usage scenario (e.g. extensions for incremental updates, for asynchronous change notifications and for encoding of multiple costs within the same cost map) have been proposed and are currently being discussed in the ALTO WG. 6. Proposed ALTO protocol extension ALTO is designed on two abstractions that are useful here. First is the abstraction of the physical network topology into an aggregated but logical topology. The second abstraction that is useful for LMAP is the notion of a "cost map". To support LMAP measurement results exposure using ALTO protocol, cost calendar needs to be investigated to see how cost calendar attributes can be used to describe task execution schedule configuration. In addition, some ALTO protocol extensions need to be considered o Additional entity property type such as measurement point or report measurement point needs to be introduced to indicate where these results are measured and who report these measurement results. o Additional entity property type such as task name or program name needs to be introduced to express what task is performed. o Addition cost metrics need to be introduced to describe what performance metrics are collected and what their values are. Xie, et al. Expires December 26, 2021 [Page 6] Internet-Draft ALTO for LMAP June 2021 7. Security Considerations TBD 8. Acknowledgements This work provides approach to get access to large scale broadband network performance data and has benefited from the discussions of large-scale network measurement data retrieval over the years. 9. IANA Considerations This document has no requests to IANA. 10. 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, . [RFC7285] Alimi, R., Ed., Penno, R., Ed., Yang, Y., Ed., Kiesel, S., Previdi, S., Roome, W., Shalunov, S., and R. Woundy, "Application-Layer Traffic Optimization (ALTO) Protocol", RFC 7285, DOI 10.17487/RFC7285, September 2014, . [RFC7536] Linsner, M., Eardley, P., Burbridge, T., and F. Sorensen, "Large-Scale Broadband Measurement Use Cases", RFC 7536, DOI 10.17487/RFC7536, May 2015, . [RFC7594] Eardley, P., Morton, A., Bagnulo, M., Burbridge, T., Aitken, P., and A. Akhter, "A Framework for Large-Scale Measurement of Broadband Performance (LMAP)", RFC 7594, DOI 10.17487/RFC7594, September 2015, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . Appendix A. Example LMAP Report The LMAP report below is in XML [W3C.REC-xml-20081126]. Xie, et al. Expires December 26, 2021 [Page 7] Internet-Draft ALTO for LMAP June 2021 2015-10-28T13:27:42+02:00 550e8400-e29b-41d4-a716-446655440000 S1 A1 update-ping-targets 2016-03-21T10:48:55+01:00 2016-03-21T10:48:57+01:00 0 S1 A2 ping-all-targets 2016-03-21T10:48:55+01:00 2016-03-21T10:48:57+01:00 0 targetrtt 2001:db8::1 42 2001:db8::2 24
S2 A1 traceroute 2016-03-21T10:48:55+01:00 2016-03-21T10:48:57+01:00 1 hop Xie, et al. Expires December 26, 2021 [Page 8] Internet-Draft ALTO for LMAP June 2021 iprtt 1 2001:638:709:5::1 10.5 2 ?
S2 A2 traceroute 2016-03-21T10:48:55+01:00 2016-03-21T10:48:57+01:00 1 hopiprtt 1 2001:638:709:5::1 11.8 2 ?
Xie, et al. Expires December 26, 2021 [Page 9] Internet-Draft ALTO for LMAP June 2021 Authors' Addresses Chongfeng Xie China Telecom Beijing China Email: xiechf@chinatelecom.cn Wei Wang China Telecom 32 Xuanwumen West St, Xicheng District Beijing 102209 Email: wangw36@chinatelecom.cn Qiufang Ma Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China Email: maqiufang1@huawei.com Xie, et al. Expires December 26, 2021 [Page 10]