Friday, February 20, 2009

Campus Architecture – Resilient Services Campus

A quick note on the important of resiliency in the campus: Business-critical applications and unified communications demand new resilient services from networks that were originally built for data applications only. These resilient services help ensure that customers, employees, and suppliers always have access to business-critical applications.

Today most enterprises run these services in the core and distribution layers of their campus networks but neglect the access layer (wiring closet), forgetting that it is critical for ensuring consistency of services and applications. Traditionally, when thinking about resilient service, redundant chassis and blocks come to mind. However, resiliency has to be more than that.

It is important to embed high availability into every possible component at different levels. In other words, in order to increase the levels of availability, you must incorporate it in different places and levels of abstraction. For example, the campus design must have redundancy at a block level, equipment level, and intra-chassis level. Think about having multiple ways to get to your services, multiple chassis that interconnect your servers, and those chassis have multiple power supplies, line cards, and other components.

As the first point of contact with the network, wiring closet switches have become the business lifeline for knowledge workers, and the first line of defense for information security. The right switch prepares enterprise wiring closet network infrastructure for present and future applications. Redundancy at a chassis level becomes more important in this case because desktops and users connect to them thru a single cable.

Also, the core and aggregation of the network must be resilient at a block and chassis level to ensure self healing and no intervention in case of a failure.

Finally, the edge of the campus must also incorporate redundancy when possible, at a device and circuit level. In other words, carrier redundancy is important.

No comments: