n outsourced to external software firms and system integra- tors. This can be considered as a vertical disintegration of the telecommunications operating industry. CSPs offer already voice and broadband services horizontally across multiple physical network layers. Also the customer relationship management applications have adopted a horizontal approach, where the same software is used across multiple network technologies instead of providing separate customer interface systems for PSTN, mobile and broadband, as was the case in the 1990s. The near future horizontalization trends are related to the network and service layers. In the network layer, operators seem to want to get rid of multiple network technologies and converge into two dominating technologies, namely all-IP and LTE. All-IP approach aims at adopting the IETF protocol stack used in the Internet also as a general communication service platform. Using ip-phone applications for voice communication (such as Skype) would bring down CSP revenue and enforce adoption of flat monthly fee charging. The CSPs are somewhat unwilling to adopt this path as long as no replacing revenue streams and business models have been identified. Applying all-IP approach to the mobile world (e.g., in form of WIMAX) has also some technical problems related to standardization and roaming. Thus the mobile operators have mainly adopted an alternative approach, long term evolution (LTE) which secures CSP investment on mobile infrastructure and provides a migration path to mobile broadband. In addition, use of SIM-card based customer lock in is still possible in the LTE architecture but not in WIMAX, mobile WLAN and other pure IP approaches. In the service layer each of the network technologies has traditionally had separate tools for service provisioning, assurance and billing. This has caused multiplication of work and tools in service creation and other OSS/BSS processes. There have been approaches to use single network technology independent tools for service creation and executi