Despite DSL, ISDN (Integrated Services Digital Network) is still quite popular among home phone users in Germany. It offers two lines, at least three phone numbers (Multiple Subscriber Numbers or MSN) and a better voice quality as well as more service attributes than analog lines. It also helps internet users who cannot get a DSL or another broadband connection by doubling the data transmission rate of the narrow-band internet connection. Here are three ISDN telephones that are available in German stores for less than EUR 100.00.