Comcast has deployed Resource Public Key Infrastructure (RPKI) on its network. RPKI is a framework designed to secure the Internet’s routing infrastructure, primarily Border Gateway Protocol (BGP) The move was welcomed by Cloudflare’s CEO Matthew Prince, who had last year voiced his concerns on Comcast not securing BGP routes. BGP leaks can cause a surge in misdirected internet traffic that eventually leads to global congestion and a Denial of Service (DoS) When this happens, chaos occurs.
Source: https://www.bleepingcomputer.com/news/security/comcast-now-blocks-bgp-hijacking-attacks-and-route-leaks-with-rpki/