  Networks (Autonomous Systems-AS) allocate or revoke IP prefixes with the
intervention of official Internet resource number authorities, and select and
advertise policy-compliant paths towards these prefixes using the inter-domain
routing system and its primary enabler, the Border Gateway Protocol (BGP).
Securing BGP has been a long-term objective of several research and industrial
efforts during the last decades, that have culminated in the Resource Public
Key Infrastructure (RPKI) for the cryptographic verification of prefix-to-AS
assignments. However, there is still no widely adopted solution for securing IP
prefixes and the (AS-)paths leading to them; approaches such as BGPsec have
seen minuscule deployment. In this work, we design and implement a
Blockchain-based system that (i) can be used to validate both of these resource
types, (ii) can work passively and does not require any changes in the
inter-domain routing system (BGP, RPKI), and (iii) can be combined with
currently available systems for the detection and mitigation of routing
attacks. We present early results and insights w.r.t. scalability.
