s in this category are complete NMS suites with almost all the popular NMS functions. The product itself is charged and the add-ons are charged a premium. Add-ons provide modules with func- tions that would not be available in the usual NMS products or given as a specialized function product by other vendors. Example of a product that falls in this category is IBM Netcool. The add-on could be a module with a set of standard adapters or a specialized function for managing IP networks. 3. Function specialized NMS: Products in this category are developed to perform a specific NMS functionality. For example, "Granite Inventory" a product of Telcordia is intended to perform inventory management and not the general FCAPS functions. Though there is competition between vendors working on NMS framework and packages, these products don't directly compete with products developed to perform specialized functions. For inventory manage- ment, the competition for Telcordia is inventory management products from companies like Cramer, MetaSolv, NetCracker, and SO on and not products like IBM Tivoli, AdventNet, or OpenNMS. 4. Domain specialized NMS: Products in this category are for managing net- works in a specific domain. For example, "netspan" a product of Airspan is for performing FCAPS functionality on the WiMAX network and not a generic product for multiple domains. OEM (original equipment manufacturers) who want to provide/add a specialized WiMAX NMS as part of their WiMAX product suite for service providers, will opt to buy netspan rather than go with a generic NMS product. 5. Hybrid type: Several combinations of the four NMS product types already discussed is also possible. This type has been termed Hybrid. For example, IBM Tivoli is an NMS framework that is developed without using open source products and hence the product is not free. Another example of the Hybrid again from IBM is Tivoli Netcool IP Multimedia Subsystem (IMS) Manager. Though the name IMS manager shows it is a domain specialized NMS, this product is buil