In today's globally connected marketplace, enterprises are rapidly becoming more decentralized, distributing increasing portions of their workforces across branch and regional offices. In many organizations, up to 80 percent of employees work in such offices. As a result, critical business functions and applications such as CRM, ERP, and email, which often require local support, are also distributed.

Branch office networking requirements are changing at a rapid pace to support these mission-critical applications. Locations require multiple networking services such as security, firewall, voice, routing, and VPNs. To deal with that, branch network infrastructures must be scalable and remotely manageable. The infrastructure must also extend to support new services and applications. Managing this infrastructure requires skilled workers and expensive resources.

Traditional branch office solutions offer enterprises two alternatives -- a set of independent and cascaded point devices, or multi-function networking products that are just collections of independent service appliances consolidated into one box. As new services are added, the increasing complexity of multiple layers presents several significant problems. For example, support for new services requires the addition of new devices, which can be disruptive. Upgrading or making a configuration change to one service can interfere with other services. These solutions often provide little or no support for remote management, leading to expensive on-site repairs. The net result for enterprises is a non-linear rise in operational costs and unacceptable levels of downtime for mission-critical applications.

Due to these inherent shortcomings, the evolution path offered by the traditional approach is unsustainable. Enterprises need branch office solutions that enable fundamental new ways for branch office networks to be built and managed. A new breed of branch office equipment called a services gateway, which unifies multiple services onto one platform, is emerging to address this critical need. To fully overcome the limitations of traditional solutions and meet enterprise requirements for serviceability and availability, this solution should be purpose-built to unify multiple branch networking services on a single platform.

Services gateways are designed to address the following key requirements of today's distributed enterprise:

• Always-available remote management access to the system, independent of the state of the system
• Non-disruptive service upgrades, configuration changes, and new service additions
• High performance and scalability with multiple services
• Unified management of multiple services

It is important to note that there are many different ways to achieve high serviceability, availability, and performance for a networking system. While many of these alternatives may be appropriate for devices in the core network (e.g., core routers), they tend to be too expensive for the branch office. Hence, the approach and design choices adopted by vendors of services gateways should provide an optimal choice, given the specific constraints and requirements of the branch office.

Always-available remote management access -- to manage increasingly sophisticated applications at branch offices, enterprises need skilled, expensive IT resources. However, enterprises cannot afford to have such people at each branch. To overcome this challenge, enterprises have to centralize management at their network operating centers and the NOC staff requires any-time remote access to all system management functions. The services gateway thus requires a separate management system with its own dedicated processors, a management plane that is separate from the data and control planes, a redundant architecture, and multiple access mechanisms to reach the system. These elements have to be combined with intelligent software processes, independent of the state of the system.

Non-disruptive servicing -- a multi-service branch office network will constantly need service upgrades, configuration changes, and new service additions, which can be major contributors to system downtime and loss of productivity. Services gateways can overcome this challenge by having a fully modular software and hardware system that allows managers to enable, disable, upgrade, or re-configure each service without affecting other services. A failure in one service should cause minimal or no disruption to other services. In contrast, an upgrade of any service in traditional solutions with a monolithic operating system requires a re-start of the base operating system, thereby affecting all services in the system.

High performance and scalability with multiple services -- a truly unified services gateway has to be designed from scratch to allow functional integration at the service level. Such architectures allow multiple services to work together rather than in logical isolation, to share information across services, and to leverage common resources. Functional integration will ensure that processor efficiency is maximized and overall system latency remains the same no matter how many service modules are added to the system.

Unified management of multiple services -- to deliver the full set of operational benefits resulting from service convergence, a services gateway has to go beyond simple integration to support unified management of all services using a common management system. In a multi-service environment, conflicts between services can be a major source of unplanned downtime. With built-in knowledge of the interactions between services, services gateways can support application-aware configuration processes that automatically detect and resolve most conflicts.

Based on true unification of multiple services, services gateways can effectively address enterprise requirements. Services gateways will enable enterprises to significantly lower the cost and complexity of managing branch office networks, maximize uptime and serviceability for mission-critical applications, and enhance the efficiency and productivity of enterprise IT staff.

Mark Weiner is senior director of marketing at NetDevices