A Single-Chassis SAN Extension Solution: ONS 15454

The ONS 15454 is capable of supporting both synchronous and asynchronous data replication. The ONS 15454 provides storage extension over SONET and DWDM networks. Some characteristics of using the ONS 15454 MSPP solution for SAN extension follow:

• Commonly used for asynchronous applications but can be used for synchronous applications as well

• Achieve connections over large distances up to 10,000 km

• Introduces higher latency than ONS 15454 DWDM

• Has a lower storage protocol port density versus ONS 15454 DWDM

Some characteristics of using an ONS 15454 DWDM solution for SAN extension follow:

• Commonly used for synchronous data replication to up 200 km

• Achieves high density of SAN extension links over fiber

When selecting the right SAN extension solution, it is important to answer the following questions:

•	How much bandwidth is needed?
•	What distance is required?
•	What is the latency tolerance of the SAN edge devices and applications?
•	How many connections are required between data centers?
•	Is an existing infrastructure (SONET or DWDM) being used?
•	What is the availability of dark fibers?
•	What managed services is the service provider offering?
•	What are the regulatory requirements for your environment? For example, some regulations require certain financial institutions to recover critical functions the same business day a disruption occurs.