The term "mission critical" could have been coined as the definition for maintaining access to electronic medical images every moment of every day. Radiology administrators and IT professionals are charged with configuring their networks to accomplish these important goals, using either commercial PACS design or non-traditional methodology. Most would agree that redundancy is the name of the game.
New York Presbyterian, the University Hospital of Columbia and Cornell in New York City
Steven Hermann, MS, RT, CRA, director of imaging, describes their current network as quite robust, designed with redundancy in archiving so that they can push and pull data from archives in two entirely separate physical locations.
Over the next year to 18 months, they are taking advantage of a shift in PACS solutions to implement new configurations and to increase redundant capabilities and bandwidth across their network. This huge healthcare enterprise complex consists of two primary campuses, the Weill-Cornell campus on 68th Street and the Columbia University campus on 168th Street on the upper West side of the city, with a data center on East 38th Street and several other remote sites.
"The system was designed to have two different archives in two different locations for the images, so that we could route from one archive or the other to the various PACS workstations," says Hermann.
Leo Bodden, network design manager for the system, describes their existing network and their plans for advancements.
Currently at least two circuits from Verizon enter each the buildings from different directions. For example, the 38th Street data center has one circuit that enters from 38th Street and the other on 39th Street to reduce the possibility of disruption.
"From 68th Street to 38th Street, there are four 50 megabit ATM [Asynchronous Transfer Mode] PCVs [Permanent Virtual Circuits]," says Bodden. "That connection is completely redundant, meaning it even goes to diverse COs [Central Offices]." Between 168th and 38th, there are four 20 megabit PVCs. Basically, the network is designed to provide redundant interconnectivity between all sites.
Bodden explains that they are in the process of constructing an optical network throughout New York City, and they've been laying dark fiber that will "go light" this month.
"We're building a dual 10 gig ring between those three major sites, and we are adding gigabit connections over to our remotes," says Bodden. "So we'll go from today where we have 50 meg circuits to 10 gig links." Again, complete redundancy insures high availability.
But they're not stopping there. In addition, they are building a microwave ring between their three primary sites.
"If we do lose the 10 gig connections, we'll have OC-3 microwaves, which are 155 megabits [Mbps] throughout our locations," says Bodden. "If we were to lose the dark fiber completely, we'd still be running." The wireless dishes on the building rooftops are designed solely for redundancy purposes, and although they provide a smaller pipe for data transfer, they would enable continuation of vital functionality.
Bodden explains that their wide area network (WAN) was designed to enable all infrastructure components to communicate, but he advises that the local area network (LAN) should be as robust as well. "We built redundancy in the LAN where we have dual paths to all of our equipment."
University of California at Davis Medical Center
Alex Lopez, system architect at UC Davis, turned to the globally-active Ciena Corp. to enable the design and implement its disaster recovery plan. The facility moves stored images and information from the electronic medical record (EMR) system between two data centers. The challenge has always been to manage huge data storage requirements from cardiology and echocardiography procedures. A Ciena 2000 Storage Extension Platform and other applications move and store that data as well as replicate it for disaster recovery purposes.
"The advantage of the multiplexing is that we have fiber channel protocols, mainframe protocols, and Ethernet protocols that we use for storage replication," says Lopez. "We use the Ciena and convert to fiber channel to move it to the other building, so we don't need to have a separate network for each one of them."
Lopez describes the approach as Ciena utilizes SONET (Synchronous Optical Network), a standard for connecting fiber-optic transmission systems, based on the bandwidth of the pipeline used during transport.