PSTN Public switched telephone network

public switched telephone network {= PSTN}

public switched tele-phone network

Private Network Public Network

public switched network

Public Switched Telephone Networks

Public Telephone Network

GSTN General Switched Telephone Network

private switched telephone network

switched telephone network

after payment type public telephone

Circuit Switched Public Data Network

Circuit Switched Public Data Network CSPDN

Circuit-switched Public Data Network

Circuit-Switched Public Data Network CSPDN

DDN public network

dissemination model of network public sentiment

LNPN Lotus Notes for Public Network

Navigation-aids Public Network System