. It may be possible to measure service quality through the use of passive and intrusive probes that provide a full end-to-end measurement. However, this approach pro- vides little information that will enable the operator to arrest or prevent service degradation. By breaking the service down into components, and making that infor- mation available to the user, it is possible to provide root cause information that will allow faster corrective action. 7.4 Industry Initiatives A number of activities within the industry are focused on SLM. Once again, the TMF has a number of projects focused on managing service quality. The TMF SLA Handbook28 gives details of the structure and application of SLAs. The TMF Wireless Services Measurements Team (WSMT) were, at the time of writing, defin- ing a set of measurables required for service quality from UMTS radio access net- work (RAN) resources. These new sets of measurements were submitted to the third-generation mobile partnership project ("3GPP") for inclusion in the Release 5 specifications. The WSMT produced a handbook29 that defines the methodology for defining the SLA parameters. The work of this team includes mapping the processes defined in the TMF eTOM³0 on to the process flow for defining SLAs. 28 SLA and QoS Handbook, TMF Version 1.0, November 2000. 29 TMF Wireless Services Team Handbook, GB923. 30 TMF eTOM Business Process Framework, GB921 version 2.5. 4 Implementing Service Level Management Workflow Active Service Monitoring Testing Passive Service CC/CR Testing/Probes Service Level Management QoS Policy Server Inventory Network Level Physical and Fault Management Logical Network Network Level Models Performance Billing Mediation Management IP/AP SS7 Link Systems Element Mgt Monitor Management Firewall Server Server MSC/VL MSC/VL Figure 7.6 SLM architecture. 7.5 Technology There are several offerings from vendors that claim to provide the technology for SLM. Unfortunately, some of these solutions do not provide complete coverage of all that is required for effec