dventNet gives the user, graphical Fundamentals of EMS, NMS and OSS/BSS interfaces to set thresholds on key performance parameters for ease of moni- toring and to generate event notifications of trouble scenarios before the actual trouble condition occurs. Security management: AdventNet Web NMS has extensive security features that include both functional and architectural features. The functional fea- tures include an initial authentication followed by an authorization window that gives authorization to users to work on the NMS based on their login ID, role, or group. Each user who wants to use AdventNet is recognized using a unique login identity (ID). The user can be assigned to a role like "adminis- trator" as there will be a specific set of functionalities permitted for the role. Users can also be grouped under a group name and functionalities permitted for the group can then be defined. Group/role needs to be created first before allocating users to a specific role/group. The architectural feature includes support for Java security model, with use of centralized RMI server for access control and use of SSL for communication. Compliancy to standards is another key capability of AdventNet that helps in making this solution suitable for multitechnology and multivendor environment. AdventNet is compliant to TMF MTNM standard and implements the NML- EML interface in conformance to standards TMF513/608/814. AdventNet Web NMS has a layered (tier) architecture (see Figure 13.2) where the functionalities (components that perform specific functionality) are grouped under five layers. They are: 1. Mediation layer: This layer has components that provide southbound inter- face capabilities. Multiple southbound protocols are supported for dynamic deployment. TCP, HTTP, RMI, and CORBA are some of the transports supported with Java API and XML interface for application development. Client layer Front-end server layer Database cluster layer Back-end server layer Mediation layer Figure 13.2 Layered architecture of AdventNet W