2Gbps--cut through the hype to the value proposition.

2Gbps will be important to IT organizations as a way to improve data transfer rates and improve application run times. The McDATA vision is, and will continue to be, farther-reaching than any one technical initiative. McDATA's vision focuses on solving pain points customers experience in their businesses and IT organizations. McDATA has been delivering 2Gbps capable products with the 6000 series Director since Q2 2001, the only high port count director available that is 2Gbps capable. In fact, the 6000 series Director is 10Gbps capable and will also be to emerging technologies like iSCSI and InfiniBand.

As an example, by delivering a protocol independent product like the 6000 series Director, our partners are able to today leverage capabilities like "constant availability" to minimize risk, no-compromise performance to increase application efficiency, industry leading management to lower the total cost of ownership, and professional services to minimize complexity and bring applications to market sooner. These capabilities can be realized while each customer's investment is protected in the future by being able to exploit 2Gbps, 10Gbps, iSCSI, InfiniBand, and application blades in the future.

McDATA is in the process of testing and validating its 2Gbps products and will bring them to market when the increased throughput can be fully realized within the SAN, and when our partners have approved and released for availability their 2Gbps storage offerings. This will be accomplished within the first half of 2002.

When customers can truly take advantage of the performance benefits of 2Gbps technology, that is when an entire 2Gbps infrastructure is available, where do they begin? An important consideration for customers planning on utilizing 2Gbps technology in their storage fabric is how their directors and switches that support 2Gbps transfer rates will interoperate with other products running either 1Gbps or 2Gbps. It is likely that implementations will be staged over time, resulting in a mixture of 1 and 2Gbps products. A solution that supports both 1 and 2Gbps is not only preferred, but also required. That is why products should be chosen that are capable of running auto negotiate implementation.

McDATA's 2Gbps 6000 Series Director and, in fact, all McDATA products, have been designed to operate as an auto negotiate implementation, capable of running at either 1Gbps or 2Gbps. When a port is configured for 2Gbps, and a 1Gbps node is attached, software within the 2Gbps device synchronizes at the 1Gbps rate. If half of the ports are connected to servers and storage that run at 1Gbps and the other half are attached to devices that run at 2Gbps the 6000 Series Director will enable a 2Gbps transfer between 2Gbps capable products and a 1Gbps transfer between Gbps capable products.

This mixture of 1 and 2Gbps device support on the 6000 Series Director also applies to McDATA's complete family of core to edge switching products. A mixture of 1 and 2Gbps capable directors or switches may be attached to the 2Gbps 6000 Series Director and operate at either 2Gbps or 1Gbps as required.

McDATA's implementation of 2Gbps technology allows for flexibility in mixing and matching either 1 or 2Gbps servers, storage devices, and switching devices. Customers can exploit 2Gbps technology in stages, continuing to utilize 1Gbps equipment to provide storage networking as required. A company's existing investment in 1Gbps equipment can be protected while the benefits of 2Gbps technology is applied in critical locations.

A logical place to start with deploying 2Gbps technology is with the Inter Switch Links (ISLs) between switching devices. In most cases the number of ISLs between switches is less than the number of external ports (connections to servers or storage) that the switch provides. This results in a concept known as "blocking", a common trait of a meshed network made up of smaller port count switches. However, if the servers are all transferring at 1Gbps, and the ISL can transfer at 2Gbps, the level of blocking can be reduced by up to 50 percent. However, a better way to address the limiting factor of ISLs is to minimize or eliminate them with a high port count director. A fabric built with a mesh of switches will be prone to significant blocking with the large number of ISLs running at 2Gbps, but there will be none with the high port count director. Not only does a fabric built on a Director-class backbone eliminate performance-robbing blocking, it is significantly easier to plan, install, and manage than one based on a mesh of switches.

An IT organization should, however, be wary of the costs associated with deploying 2Gbps technology within their enterprise. The cost to replace all HBAs and switches and upgrade or replace storage systems can be extensive. Even a modest configuration can cost hundreds of thousands of dollars to convert to 2Gbps. In many cases, such a cost is tough to justify, especially when most applications are not even filling a 1Gbps pipeline. What makes more sense is to determine where throughput is being bottle-necked within the network. This will likely be with an application that is throughput starved, such as video streaming or disaster recovery backup or synchronization. Then, the investment in 2Gbps infrastructure can be made where it will provide benefit. This is technically possible because most vendors' 1 and 2Gbps equipment can co-exist. A key tactic would be to deploy protocol independent equipment such as McDATA's 6000 Series Director, which enables users to deploy 1Gbps today, and upgrade later when the situation dictates. One of the key challenges in such a deployment, however, is identifying where the network bottlenecks reside.

Legacy performance tools were designed to measure performance with a direct attach disk. With the introduction of a SAN into the equation, identifying the performance effect of the network needs to be taken into account. A powerful SAN management and monitoring application is the best answer. McDATA's SANavigator provides the user with a powerful management tool to measure the existing throughput of the retire storage network. Graphical displays can easily pinpoint "hot spots" within the network. This enables enterprises to stage their 2Gbps deployment to segments that san profit from the higher bandwidth, saving unnecessary downtime and expense. Once 2Gbps or some other network initiative is deployed, one can easily compare the "after" performance effect of the initiative. No other storage network management application in the marketplace today can match SANavigator's capabilities in this area.

Remember, 2Gbps can provide a performance boost for some customers, but there are a number of factors to consider.

In order to fully utilize 2Gbps, an IT organization must replace or upgrade all elements of the storage network, including HBAs, switches, directors, and storage. Even then, a majority of applications running today do not fill a 1Gbps pipeline. To make the most of any 2Gbps investment, make sure you can identify where the bottleneck is, and then apply the 2Gbps investment there.

By following this process you can be assured that your 2Gbps investment is paying dividends, while limiting unnecessary downtime and expense.

www.mcdata.com

Jim Miller is a senior product manager at McDATA Corp (Broomfield, CO).