Timeseries monitoring systems such as Prometheus play a crucial role in gaining observability of the underlying system infrastructure. These systems collect timeseries metrics from various system components and perform monitoring queries over periodic window-based aggregations (i.e., rule queries). However, despite wide adoption, the operational costs and query latency of rule queries remain high. In this paper, we identify major bottlenecks associated with repeated data scans and query computations concerning window overlaps in rule queries, and present PromSketch, an approximation-first query framework as intermediate caches for monitoring systems. It enables low operational costs and query latency, by combining approximate window-based query frameworks and sketch-based precomputation. PromSketch is implemented as a standalone module that can be integrated into Prometheus and VictoriaMetrics, covering 70% of Prometheus' aggregation over time queries. Our evaluation shows that PromSketch achieves up to a two-order-of-magnitude reduction in query latency over Prometheus and VictoriaMetrics, while lowering operational dollar costs of query processing by three orders of magnitude compared to Prometheus and by at least 4× compared to VictoriaMetrics with at most 5% average errors across statistics.

Methods for promoting flexible use of the radio frequency spectrum in microwave radiometry are examined in order to assess the potential for future spectrum sharing paradigms. Results are shown that suggest that geophysical product retrieval performance can be maintained under a variety of channel frequencies and bandwidths.

Space-Air-Ground Integrated Networks will facilitate seamless user experiences across a variety of 6G applications. The deployment of these networks will necessitate new approaches to spectrum allocation. Spectrum access by passive microwave sensors for earth-based and space-based scientific applications represents a spectrum use application having unique attributes that motivate consideration of spectrum sharing between these “incumbents” and commercial users to ensure the most efficient utilization of available frequencies across applications. Toward this end, we propose an economic framework where incumbents have priority use, with a primary and secondary commercial tier underneath. For commercial users, the option to join the primary tier is based on a model of short term post-paid leases of spectrum, while the secondary tier is available to join at no cost. Using a joint game-theoretic and queuing-theoretic model, we find that for practical parameters the revenue maximizing equilibrium is: 1) stable in the Evolutionary Stable Strategy sense; 2) associated with the maximum priority upgrade fee customers are willing to pay; 3) associated with an equilibrium where all customers wish to join the priority class; and 4) socially optimal. We validate our findings leveraging trace data from satellite radiometers operating in the vicinity of Boston, Massachusetts.

The Citizens Broadband Radio Service (CBRS) is a spectrum sharing framework on the 3.5 GHz tier with three priority tiers: the incumbents, priority commercial users (PAL), and general commercial users (GAA). Thus, commercial users compete for resources within the second and third priority tiers. The interaction between commercial providers and customers is complicated by the presence of the incumbents, who impact the availability of spectrum but bypass the market entirely. In particular, PAL customers are themselves subject to preemption even with the priority purchase. In this paper, we propose a game-theoretic framework to shed light into the equilibrium outcomes and the impact of the incumbents into these. We determine that there exist several possible equilibrium regions, including one with a unique mixed equilibrium which is stable in the evolutionary stable strategy sense, and others featuring unstable mixed equilibria and stable pure equilibria. We show that for fixed parameters, the maximum possible revenue a provider can obtain is associated with a stable equilibrium and is thus guaranteed. However, changes in incumbent behavior can result in phase changes which have a sizable impact on the maximum potential revenue.