65 Commission’s prior, longstanding regulatory definition of “public switched network” was in effect. Because the Commission at the time had defined the “public switched network” by reference to the telephone network, it is unsurprising that Congress would have assumed the term to have that meaning. But that assumption by no means indicates that Congress meant to divest the Commission of the definitional authority it had expressly granted the Commission in section 332(d)(2). We do not understand Congress’s express grant of definitional authority to have come burdened with an unstated intention to compel the Commission to forever retain a definition confined to one specific type of “public switched network,” i.e., the telephone network. We therefore reject mobile petitioners’ counter-textual argument that the statutory phrase “public switched network” must be understood as if Congress had used the phrase “public switched telephone network.” Instead, the more general phrase “public switched network,” by its terms, reaches any network that is both “public” and “switched.” Mobile petitioners do not dispute that a network using both IP addresses and telephone numbers is “public” and “switched.” As the Commission explained, its expansion of the network to include the use of IP addresses involves a “switched” network in that it “reflects the emergence and growth of packet switched Internet Protocol-based networks,” and it also involves a “public” network in that “today’s broadband Internet access networks use their own unique addressing identifier, IP addresses, to give users a universally recognized format for sending and receiving messages across the country and worldwide.” 2015 Open Internet Order, 30 FCC Rcd. at 5779–80 ¶ 391 (emphasis added). The Commission thus permissibly considered a network using telephone numbers and IP addresses to be a “public switched network.”