
252 ◾ IP Communications and Services for NGN
Vertical versus Horizontal Integration Services
ere are two distinct paradigms for provisioning telecommunication services in
industry: vertical and horizontal integrated services. ese two concepts are related.
Traditionally, almost anyone who has used fixed telephony and the Internet has had
to use services through vertically integrated service provisioning.
Vertically Integrated Services
Legacy service offerings in traditional networks integrate and offer services in a ver-
tical manner (Figure 13.4). In this structure, each service has its unique functional-
ity for charging, presence, group and li ...