%% You should probably cite rfc9439 instead of this I-D. @techreport{ietf-alto-performance-metrics-08, number = {draft-ietf-alto-performance-metrics-08}, type = {Internet-Draft}, institution = {Internet Engineering Task Force}, publisher = {Internet Engineering Task Force}, note = {Work in Progress}, url = {https://datatracker.ietf.org/doc/draft-ietf-alto-performance-metrics/08/}, author = {Qin Wu and Y. Richard Yang and Young Lee and Dhruv Dhody and Sabine Randriamasy}, title = {{ALTO Performance Cost Metrics}}, pagetotal = 29, year = , month = , day = , abstract = {Cost metric is a basic concept in Application-Layer Traffic Optimization (ALTO), and is used in basic services including both the cost map service and the endpoint cost service. Different applications may use different cost metrics, but the ALTO base protocol documents only one single cost metric, i.e., the generic "routingcost" metric; see Sec. 14.2 of ALTO base specification {[}RFC7285{]}. Hence, if the resource consumer of an application prefers a resource provider that offers low-delay delivery to the resource consumer, the base protocol does not define the cost metric to be used. ALTO cost metrics can be generic metrics and this document focuses on network performance metrics, including network delay, jitter, packet loss, hop count, and bandwidth. Additional cost metrics may be documented in other documents. When using an ALTO performance metric, applications need additional information beyond the metric. In particular, its "cost-source", such as it being an estimation or an SLA, is key to define the meaning of a performance metric. Hence, each ALTO performance metric should include the "cost-source" of the metric. To report an estimated value of a performance metric, the ALTO server may derive and aggregate from routing protocols with different granularity and scope, such as BGP-LS, OSPF-TE and ISIS-TE, or from end-to-end traffic management tools. These metrics may then be exposed by an ALTO Server to allow applications to determine "where" to connect based on network performance criteria.}, }