As services are increasingly centralized in public clouds, understanding the nature of Internet Background Radiation (IBR) hitting these particular environments is an important part of understanding their overall security posture. Classical network telescopes, long the cornerstone of IBR research, face hurdles here: their surface area is shrinking, and their well-known address ranges are easily avoided. We present a multi-cloud view of IBR in this paper. We deploy a passive, distributed network telescope with 336 IPs across five major cloud providers. We compare traffic from our cloud telescope with data from two classical telescopes, a large well-known (/9 + /10) and a small unknown /16, to analyze observational biases. To enable a fair comparison across very different telescope sizes, we tune a scan detection algorithm to determine appropriate thresholds. Our findings reveal that IBR in the cloud is strongly provider-dependent rather than geography-dependent, highlighting the necessity of multi-cloud deployments for comprehensive visibility of IBR in the cloud. Our cloud telescope also captures a distinct set of scanners, confirming that scanning activity is not uniform across the IPv4 space, and we confirm that small, distributed telescopes are ill-suited for observing random events like DDoS backscatter. Our work underscores that monitoring must evolve beyond classical telescopes to include diverse, multi-cloud vantage points to accurately capture IBR.

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