WAN Optimization
By Shawn Cooney
Given that an enterprise’s data is considered to be one of the most important corporate assets, data backup and replication processes are critical functions for IT staffs. For business continuity and regulatory compliance purposes, IT staffs must ensure that corporate data can be completely restored within a short period of time in the event of a disaster. Otherwise, IT staffs are placing the enterprise at a huge risk.
Most staffs set up storage environments with little consideration of how a wide area network (WAN) can negatively impact backup or replication times. However, a little planning can pay big dividends in the value of the data saved and the associated build-out costs. What goal should IT staffs target with their data replication and backup processes? The short answer is that IT staffs need to reduce the risk of data loss and down time through more-frequent, high-performance backups at the lowest possible cost. The complete answer is that data replication and backup must be:
Quick: Require a minimum transfer time, allowing more-frequent backups that contain “fresher,” more-accurate data
Efficient: Consume a minimum of network resources
Manageable: Require limited IT staff time, keeping overhead costs low
Flexible: Adapt to changing business requirements
Scalable: Scale as the volume of backup and replication data grows
Reliable: Retrieve data without data corruption
Economical: Be built with the most cost effective infrastructure
Data replication and backup involves moving a large volume of data between corporate data centers, branch offices and replication sites over a WAN. Storage managers are likely to encounter insufficient bandwidth, high latency, network congestion, chatty protocols, out-of-order packets, packet loss, and redundant data transmission that interfere with their efforts to meet their recovery time and recovery point objectives (RTO/RPO). Any or all of these factors can cause long backup windows, possible data loss and high costs, a far cry from the ultimate goal of high performance backups at low cost. Some backup and replication windows are so long that IT staff is unable to keep corporate data current. A solution must be found to shrink backup windows to ensure that corporate data does not become old and useless.
Most storage managers believe that adding more network bandwidth will shrink backup and replication windows. However, adding bandwidth can be very expensive, and that cost will continue to grow as the volume of corporate data grows. Unfortunately, this expensive lesson leads to the discovery that adding more bandwidth does not solve the problem. Rather than adding a fat pipe for data transfers, storage managers need to focus on improving the efficiency of backup and replication operations.
A Better Approach: Virtualize Storage Infrastructure and Add WAN Optimization
The first step in making enterprise data replication and backups even more efficient is to virtualize the enterprise’s storage network infrastructure. By doing so, IT staffs can make better use of their total storage capacity, gain more flexibility and reduce storage costs.
The second step is to improve the efficiency of data backup and replication transfers over the WAN with a WAN optimization solution. WAN optimization reduces the amount of data traversing the WAN through these means:
Network data compression – Reduces the volume of data on the network
Network data deduplication – Eliminates redundant data being sent across the WAN
By reducing the amount of data being sent by the backup and replication process, storage managers can more frequently back up and replicate incremental data streams more efficiently, solving the data age, risk and accessibility problems.
WAN optimization requires a symmetrical deployment where a WAN optimization solution is installed at the enterprise data centers, branch offices and data replication sites.
See Figure 1.
Figure 1: Virtual appliance WAN optimization software deployed at data center, branch offices and replication (or disaster recovery) sites for high performance data backup and replication
Best-in-class WAN optimization solutions should provide upwards of a 90 percent improvement in backup and replication times and an equal amount of network bandwidth savings. For example, if your RTO/RPO targets for incremental snapshots of 50 GB of data are every 30 minutes throughout the day — yet in reality it takes you four hours, a WAN optimization solution can enable you to meet your goals and eliminate the high cost of adding more bandwidth.
Hardware or Software WAN Optimization
Hardware-based WAN optimization vendors continue to try to convince the marketplace that hardware is still the best option for WAN optimization. However, IT staffs are beginning to better understand the many benefits of software-based WAN optimization virtual appliance solutions, including a lower total cost of ownership, better scalability and increased manageability.
Software-based WAN optimization virtual appliances are typically more competitively priced than hardware appliances and, in many cases, can improve performance and reduce bandwidth load with no new hardware purchases. Virtual appliances for WAN optimization also leverage the scalability, flexibility and manageability of the virtualization system that supports them. Some software-based solutions cost 30 percent less than hardware appliances and offer as much as a 60 percent TCO savings in combined CAPEX and OPEX.
With the widespread adoption of virtualization, installing hardware outside the virtualized environment is contrary to a company’s entire virtualization strategy. Virtualized WAN optimization solutions fully leverage the system resources of the virtual machine and can scale to support many more accelerated transfers than hardware appliances with fixed resources. For this reason and more, WAN optimization solutions are trending toward software-based virtual appliance solutions.
To take full advantage of a virtualized environment, ideally, a WAN optimization solution must be hypervisor “agnostic,” which means it must be able to run on any industry-standard hypervisor, along with any other application (not as a dedicated appliance with limited support for hosted virtualization). Furthermore, the solution should be easy to install and managed at all sites using the same virtualization tools used throughout the virtualized enterprise network.
Virtualized Storage and Virtual WAN Optimization
The combination of a high performance storage environment and software-based virtual WAN optimization solutions makes for high performance, highly efficient, low-cost data backup and replication. Virtualization is the key to enabling the best use of storage and optimization resources. It also provides the greatest flexibility and scalability and the ability to keep pace with corporate changes at the lowest total cost of ownership.
Shawn Cooney is the director of research and co-founder of Certeon.
