These companies have the Tier 1 classification. – It means that they are networks with worldwide coverage (in most countries) and thousands of interconnection points with the TCP IP protocol. 

The TCP IP (protocol is a data communication protocol used on the Internet). This protocol is the basis of communication for all the applications that we know and use every day, for example, emails, instant messaging, streaming (Netflix, YouTube, etc.), social networks, videoconferencing applications etc.