Valtteri Lehtinen Security Research & Curiosities | Helsinki, Finland About Posts Categories RSS What kind of systems are there in the Finnish telephone network today? This question appeared to me a while ago when leafing through an old telephone directory from the early 2000s. There are at least ordinary subscribers, business customer support lines, voice mails, and fax machines. Subscribers and customer support lines are not of special interest to me. I am more interested in automated systems that let the caller interact with them somehow. Voice mails and fax machines fit this definition. But is there something else as well? As the telephone network predates the Internet in Finland by over 100 years, the systems in it can be very old and obscure. Before the Internet gained popularity, these systems were used to provide similar services we ...