the use of web services there is a need for standards (or possibly proprietary solutions) for AAA, payments, QoS, security and management. 3.13.1 SIM APPLICATION TOOLKIT (SAT) The SAT function (SCS) is used for downloading applications on the SIM card in the mobile terminal. 3.13.2 TRANSPORT The hypertext transport protocol (HTTP), which is used for browsing applications on the Internet, provides the semantics of requesting and transferring information between Networks and Technologies servers and clients in a distributed and collaborative way. Most often, the information requested from the server consists of HTML objects. However, HTTP is not restricted to HTML - essentially any information can be requested and transferred between the client and the server, including media objects. HTTP is used on top of TCP. 3.13.3 AGENT TECHNOLOGY Intelligent software agent technology is one of the most important emerging IT technolo- gies of the last years. The technology plays the role of an important enabler for highly distributed and complex solutions, self-organizing and collaborative systems. In particu- lar agent technology is predestined for the integration of web services being supported by suppliers. 3.13.4 RELIABILITY ISSUES Future networked systems will run applications whose behavior cannot always be antic- ipated, and this is a problem that did not exist in traditional telecom. These applications are composed by dynamically composed services which may have bugs that in addition run in an unpredictable environment. 3.14 KEY ENABLERS 3.14.1 H.248 (H 248. ITU 1999. Megaco1999. Final approval of a common protocol 2000. IETF RFC2885, RFC2886.) H.248 is a new protocol that enables a layering split between connectivity and control. See Figure 3.47. We are used to 'horizontal' protocols for signalling, management and other purposes, but this is a master-slave 'vertical' type of protocol. The horizontal protocols might then be called peer-to-peer protocols. A master/slave model permits short time to market. Gateways can b