The Business Case for Storage Networks [Electronic resources] نسخه متنی

Storage Environment

As patients begin their treatments at the CTRC, critical data and vital records are collected. As the patient progresses through his or her treatment cycle, data pertaining to dose distribution, treatment planning, physician consultation, and diagnostics are collected and stored through a series of applications.

Note

Luter states that the effects of HIPAA legislation are just now beginning to appear, and that it is hard to estimate the exact impact the new health care legislation will have on their storage infrastructure.

Growth rate in storage capacity at the CTRC is currently directly correlated to the number of new patients seen each year. HIPAA legislation and the CTRC's association with the CTRC Institute for Drug Development (IDD), Title 21 Code of Federal Regulations (21 CFR Part 11) might in the near future create a spike in the amount of data the CTRC is required to manage.

In terms of the amount of data captured, by far the most resource-intensive area is the application of positron emission tomography (PET) technology.

Of the 13.6 TB of raw storage used by the CTRC, 3.4 TB is unutilized direct-attached storage (DAS). The remaining 10.2 TB is consumed by a mixture of extremely high-resolution positron emission tomography and computed axial tomography images (also known as CAT scans or computed tomography [CT]), and magnetic resonance imaging (MRI) data sets. When these images are combined to form a single file, the average size of each file is roughly 100 MB.

Note

PET technology is similar to both CAT and MRI scanning in that all three techniques create images of the patient's body for diagnostic and analytical purposes. PET differs from MR and CT, however, in that it is capable of measuring chemical and biological changes in the body's functions, which in many cases can assist physicians in forming a more accurate diagnosis earlier in the course of the disease.

To provide caregivers at the primary location and researchers at the secondary location the same access to always-available, mission-critical patient and research data (including patient image scans), the CTRC needed to configure and implement an architecture that was not only scalable and highly available, but also cost-effective. Using the Cisco SN5420 iSCSI router and eventually the SN5428, Luter and his team were able to share the Gigabit Ethernet link between the two locations with another mission-critical application, VoIP, over the corporate WAN. The corporate IP backbone is comprised of 11 Cisco Catalyst 4006 series switches, two Catalyst 4506 switches, and one Catalyst 4507 dedicated to Layer 3 traffic. This integrated topology approach allows the CTRC to have a highly available, converged network at minimal expense.

Note

The migration from a traditional PBX to IP telephony in 2002 saved the CTRC $50,000 in a single year solely in terms of telephony maintenance and infrastructure cost reductions. The impact of IP telephony on productivity has yet to be measured.

A mix of PC-based 1u servers in each location (45 in total), most running Windows 2000 Server, accesses the 6.1 TB of mid-range Clariion storage via what is commonly referred to as a metro cluster. Only changed data is replicated between the two locations and although this architecture does provide for some level of redundancy, Luter is quick to point out that the environment is configured primarily for high availability and not necessarily for business continuance. Critical patient data is kept synchronized between both locations so that both the doctors interfacing with the patients and the researchers analyzing the treatment data have the most up-to-date and accurate picture of the patient's health.

Figure 6-1 details the iSCSI infrastructure at the CTRC. In this example, redundant pairs of SN5428-2 Cisco storage routers in each location provide data transfer services of both patient image data and server boot data between both locations.