The architectures of two enterprise management software products, Sun MC 3.0 softwarean EMS solution and a development environment for extending the capabilitiesand AdventNet WebNMS 2.3a standards compliant development environment that has gained acceptance in the Telco environments. The following sections detail the features that produce the benefits of these two products.
Sun MC 3.0 Software Architecture
Sun MC 3.0 software evolved from several generations of Sun Network and Systems Management Tools. Starting with SunNet Manager platform, in the late 1980's, the architecture consisted of a simple manager-agent-manager model. SunNet Manager platform was extensible and included a remote procedure call (RPC)-based communication model between a manager and agents. SunNet Manager platform served its purpose well for LAN deployments, but reached limitations in larger enterprise solutions. Sun's subsequent generation product, the Solstice Enterprise Manager™ software, was designed for large enterprise deployments. Solstice Enterprise Manager software was scalable, flexible, object-oriented, and was targeted as a development and management platform out of the box. Solstice Enterprise Manager was highly extensible, and supported SNMP, CMIP, and Telecommunications Management Network (TMN) protocol. The rapid adoption of Java technology-based management applications created another next-generation product, Sun Management Center software, (version 3.0 is the current release as of the date of this article). Sun MC 3.0 software is a comprehensive systems management tool for managing Sun servers, storage, and the Solaris™ Operating Environment. Sun MC software is also a flexible framework with independent distributed services that are available to management applications and third-party management products. The architecture includes a modular pluggable architecture that can add and remove Java technology and non Java technology services.
Sun MC software is designed primarily to manage Sun Systems well. AdventNet WebNMS is designed to manage a variety of devices by integrating other vendor-specific EMS products. The integration of Sun MC and AdventNet WebNMS softwares, permits a flexible and effective solution, because every vendor knows how to manage their own devices best.
FIGURE 6 shows a high-level overview of the Sun MC 3.0 software architecture. Sun MC software consists of following tiers:
Client TierManagement clients access the server through a variety of protocols and technologies, such as a Web browser and Java application.
Server TierInterfaces with the client accepting and processing requests, and routes to the appropriate service or agents. The server also propagates alarms and event messages to the clients. The server is a central control center for all distributed information. Sun MC 3.0 software offers a comprehensive set of APIs for integration with other management systems, and empowers developers in creating sophisticated management applications.
Agent TierResides on the managed device and provides the communication interface between the native device and the Sun MC software server process.
FIGURE 6 Sun MC 3.0 Software High-Level Architecture Overview
Sun MC 3.0 software also has many of the core NMS functions, such as Event Services, Topology Services, Configuration Services, etc. The Sun MC software agents are intelligent agents, far more sophisticated than the traditional simple SNMP agents that only perform limited operations. The Sun MC software agents are dynamically configurable and autonomous.
Sun™ Developer Management Center is a separate product, which provides various APIs and tools to create not only management applications using the exposed client APIs, but also to extend the capabilities of the Sun MC software by creating loadable modules that run in the server tier. These modules can access the services shown in FIGURE 6 and create sophisticated event filter and correlation services. The server APIs allow the integration and creation of new services, such as emitters of notifications, receptors of events, protocol modules, etc.
AdventNet WebNMS 2.3 Architecture
FIGURE 7 shows a high-level overview of the AdventNet WebNMS architecture.
The clients can be Java application or browser-based. They interface with the front-end Web servers and are typically load balanced by a multilayer switch. The core functions include a discovery engine that maps discovered devices to a managed object and is defined by a software class. This information is then stored in the database. The event manager includes a hierarchical structure starting from a trap manager that identifies the trap and creates an event object. This object is then parsed to create alarm objects. At each level, redundant data is discarded and events are correlated. The map server controls the display, including the displayed objects and appropriate backgrounds, when zooming in and out. The configuration server stores the configuration of all discovered devices, and is capable of reconfiguring a device as needed. The polling engine performs periodic polling for status and performance data.
FIGURE 7 AdventNet WebNMS Platform Overview
FIGURE 8 presents an overview of the components in AdvenNet WebNMS and the interactions between them.
FIGURE 8 AdventNet WebNMS Platform Architecture
Each component can be distributed. There can be one or more components of each type based on performance, scalability, and availability requirements. There are five tiers that are detailed in the following sections.
Mediation Server Tier
The mediation server (or management) tier provides XML mediation for all southbound management protocols like SNMP, TL1, CORBA, TFTP, XML, CLI/Telnet, etc. A provider interface facilitates integration of other protocols. Common management functions are handled in this layer, making the protocol providers limited with protocol-specific operations only. The management server provides multiple interfaces for application development like XML message interface, Java technology, APIs, etc.
The back-end server tier consists of the core business logic related to management functions like fault, configuration, performance, security, service provisioning, etc. The main aspects of the back-end server tier are:
Core Management Performs functions like event correlation, alarm notification and management, template-based provisioning, batch configuration and rollback, etc.
Module ManagementA module control interface facilitates the starting and stopping of modules independently.
Security and AuditAll the back-end tier modules support authorization and audit, so that the various administrative operations can be traced.
Any relational database management system (RDBMS) that provides a Java Database Connectivity™ (JDBC™) software driver is supported. State information can be maintained in a database, making it easier to distribute the components and handle failover. This tier allows a solution to leverage the benefits of transaction support, database synchronization, and object locking for data integrity, security, and availability.
The front-end tier consists of the Web container that provides Web access to management information, the client communication management module, and the Enterprise JavaBeans™ (EJB™) technology session beans for the management functions. These items generate views for the clients and forward commit requests to the back-end tier. The main aspects of the front-end server tier are:
Client communicationVarious transport protocols, such as TCP, Java™ Remote Method Invocation (Java RMI) technology, HTTP, HTTPs, SSL, etc., are used.
Session beansThe stateless, EJB technology deployable session beans generate views from the database based on client requests.
Updates to clientA subscription-based notification used to allow the front-end tier to handle high rates of updates to the clients. In this model, clients register for the updates they are interested in, and the front-end tier server notifies them of any changes.
The J2EE configuration client (for rich GUI) and the HTML client (for Web access over low speed links) models are provided.