Planning the modern data network

While all roads may indeed lead to Rome, all of today's in-building technologies appear to lead to a data network. In the past, there were simple computer networks, a series of connections from the desk-top computer to what was referred to as a closet, wiring closet, or communications closet. Phones may have also terminated within this space, but not much else. Other building technologies generally had their own inherent closet or space; there was not a lot of mixing, and when there was, it was a mess.

With the advancement of such factors as Power Over Ethernet and pure Internet Protocol capabilities, coupled with the concept of universal cabling, more and more services are being placed on the computer network. As a result, the information technology network within a healthcare facility has become as critical as any other building utility. This has caused some significant changes to the space required to house it all.

The closets are no longer called closets; they are called now Communications Equipment Rooms, Shared Technology Spaces, or some equivalent. This change in name has come about in an attempt to change attitudes about the space, i.e., call it a closet and you can expect it to look like one. Computers and phones are not alone in these spaces anymore. Today's shared space also includes building security access control and video, building automation, nurse call, overhead paging, cable TV and other patient entertainment/education, critical physiological monitoring networks, location-tracking services (such as RFID), GPS clock repeaters, and other clinical and nonclinical systems. Because of this merger of technology platforms, a rethink of IT network topologies and spaces is necessary.

There are two very different physical areas to consider when planning a new or refreshed IT environment for healthcare: the physical topology and the physical space. Physical topology refers to the network of interconnections required to make the circuit work within the building/s. These are the pathways (conduit or cable trays) and media (fiber or copper cable) that traverse from one point (communications room) to another (end user or device). Physical space refers to the actual walls that create the shared environment or communications equipment room that securely house these services on each floor of a typical facility.

Topologies

There are three main points of access, or layers, that make the most sense for a hospital building: Core, Distribution, and Access, as represented by figure 1. The core layer connects buildings together, the distribution layer connects buildings to the core(s) and to the access layer, and the access layer connects the distribution to the end user.

A typical topology includes a main communications space located somewhere within the building (core and distribution are shared here in some cases-and, no, it does not need to be located in the basement!). This main room would connect to other buildings and to the communications rooms within the floors. And these communications rooms are connected to the end users be they humans, wireless access points, alarm or other event management points, employee time clocks, etc. Another way to look at this is by visualizing an upside down pyramid, in which the core is the small section on the bottom, moving up to the larger distribution section, and finishing up at the widest part with user and device access.

For a more robust network, redundancies can be added to any point within the topology, as represented by figure 2. In this example, two core locations are tied to each other and two distribution areas (buildings) are redundant to the cores, redundancy being required because of the critical nature of the services. Because of the costs associated with a redundant topology, organizations should plan which facilities, by type, should be considered critical enough for redundant pathways. For example, a facility that provides direct patient care should be connected to multiple core locations, while a facility office building would generally not require such additional expense. Although not a trend yet, there are a few hospitals that have created redundant capabilities from diverse communications equipment rooms to nurse stations and other critical areas.

This layered topology approach creates flexibility, in that additional buildings can be “snapped on” without disruption to any part of the network. In addition, the design creates a standardized cost expectation when building new or adding to an existing facility. This is especially important when communications between the IT departments and facilities revolves around costs associated with new construction. With the redundancies that this solution offers, topology decisions can truly be made based on criticality and costs, and not just on one or the other.

Space

There are two types of communications equipment rooms to consider: a typical access layer space located within 285 wired feet to the farthest connection point, and a large building entrance room located anywhere within the building, typically on a lower level within 50 wire feet of an exterior wall. As explained above, the access rooms are for end user devices to access the network, and the entrance rooms are for connections to the distribution and core(s), as well as serving as home to the PBX systems and all headend services (meaning main core equipment at the headend), including CATV, patient entertainment, nurse call, paging, clocks, time keeping, dictation, radiology, and lab servers.

If a redundant core and/or building distribution is planned, consider one large room on a lower level and one large room on a higher level. Don't get caught up in requiring that these rooms be located in the basement and in the penthouse. Remember, building a facility is all about give and take.

Obviously, with so many technologies merging onto the IP platform, the space required within the communications room has increased as well. Do not assume that a merger of technology and a collapse of equipment are synonymous-they are not, and this needs to be communicated clearly because this false message is commonly accepted. As facilities move from the traditional telephone systems of the past to the new IP-based systems, the legacy concept of having a telephone wall field has been replaced by the design of telephones connected to what was once considered a data rack. So while the wall use for this purpose shrinks, the space required for racks must increase.

Fear not, however-the walls will not be empty. Replacing the tangle of wires that once supported telephones are the mounted cabinets housing components that operate patient entertainment, building security, nurse call, and other systems. In addition, the cable TV, GPS clock repeaters, and some paging system devices are wall-mounted. This wall space is a valuable and limited resource. It should be space planned with detail akin to the effort dedicated to the program space on a floor.

By using solid design principles and knowing which systems have a propensity to change, static systems can be mounted higher on the walls, leaving room at working height for those systems requiring greater activity. Always mount cabinets to plywood backer board according to local codes, of course, and make sure contractors know upfront where in the communications room you want their equipment installed, otherwise they'll likely take prime space front and center on a “first come, first served” basis.

All this means that the equipment racks are going to get crowded now. Common components found in the racks today include patch panels, network switches, UPS systems, patient entertainment and education, IP-based intercom and paging systems, nurse call, physiological monitoring, and more.

Most hospital staff attempt to separate clinical engineering and facilities systems from data and voice networks. Don't. Doing so will cause a decrease in program space outside of the rooms, since the equipment rooms will need to become larger to facilitate so-called fiefdom racks, i.e., equipment racks viewed by contractors or departments as exclusive to them. No one really wants to create additional spaces to “keep people away from my stuff.” Besides, electrical and HVAC systems would need to be sized to accommodate this separation and that costs money. Departments should work together to share the space; after all, these are enterprise-supporting systems, not individually owned fiefdoms. Take each other to lunch and get to know one another. Build trust and share. It's all for the betterment of the enterprise.

Here's some advice based on trial and error: Perhaps the best method of mounting devices and panels on the equipment racks is not to separate equipment from cable, as shown in figure 3. This common method looks great on paper, but creates a serious “rat's nest” of cabling between racks and can effectively increase average mean time to repair a failure. It is best to build from the top of the rack down with patch panels, and from the center of the rack down with electronics equipment. This method decreases the need to cross racks to create connections and brings about a cleaner look.

Other solid design ideas include color-coded patch cords, rack-mounted power strips plugged into rack-mounted UPS systems, and horizontal wire managers installed between each patch panel and each network device, any or all of which can be discussed with consultants involved in this field.

Patch cords can be purchased in a variety of colors. Choose colors based on the service that the connection provides. For example, red may be for critical biological devices, green for SNMP management (SNMP being Simple Network Management Protocol for conveying problem alert messages), yellow for a standard data outlet, blue for IP cameras, and so forth. Do the same for optical fiber: orange for 62.5 micron, yellow for 9 micron, and aqua for 50 micron. Laminate and post this color code sheet within each communications room so that it can be followed readily.

The goal is for maintenance to be able to walk into a room and read it like a book without touching anything. When this is possible, the mean time to make repairs is decreased and the training curve for new staff is flattened. And don't worry about the color of the low-voltage cable behind the walls (unless mandated by local codes), it doesn't matter. If blue cable is run behind the wall for wireless access points, for example, and tomorrow it is determined that certain access points are no longer needed, that blue cable cannot be used for anything else except a wireless access point unless the set standards are violated. Conversely, without worrying about these color standards, a simple change of the patch cord allows the reuse of that otherwise abandoned cable-now it's a camera, tomorrow it's a TV, etc.

Rack-mounted power strips are an effective method of controlling cables behind the equipment-and, let's face it, keeping a clean room is all about control, especially if the facility is functioning under Service Level Agreements. Mount the power strips backwards, behind the racks, and try to purchase strips that do not have built-in on/off switches because, with these, one bump and the network will be down.

Strips should be plugged into rack-mounted UPS systems in the communications equipment rooms. In the larger building entrance room, racks should be powered from stand-alone UPS systems sized according to current and anticipated future use. For a few more dollars the power strips used for SNMP can be dual-fed and connected with an SNMP or Building Management System (BMS) to reduce the mean time to restore service.

Horizontal wire managers are cheap, so use them between everything. Control is more important than capacity-enough said.

Another method of controlling the space within the communications rooms is to not allow file servers to be installed within them. The large building entrance room should be the central location for all file servers and headend equipment, not the access spaces within the floors. There are several justifications for this, including a more controlled space for outside contractors to enter, rooms that are better suited to handle today's HVAC requirements, and the fact that smaller communications rooms cannot scale to house unknown future equipment. Sure, departments may balk at this concept-they want their server down the hall from their office-but once the controls are explained, departmental staff generally fall in line.

Many of the clinical engineering systems, such as telemetry and bedside monitoring, are sold as turn-key systems these days. The manufacturer may claim that these devices “must” sit at the nurse's station or within the communications room on that specific floor, and in many cases some portion of this is true-but resist the sales pitch; not all of the cabling for these systems needs to run to the nurses' station. Manage all of the cabling and networking from a central point: the Communications Equipment Room. And not all of the dedicated networking hardware they included in the proposal may be necessary; some may already exist in the equipment room. More could be said about all this, but this discussion will suffice for now.

One final point: Let's assume this is a new hospital of 700,000 square feet gross. A typical floor communications equipment room should be at least 12 x 13 feet; the main building entrance room should be at least 30 x 30 feet, and the secondary entrance room, in the event redundant topologies are employed, should be at least 15 x 15 feet. When people claim-and they will-that the IT network equipment takes up too much space, remind them that this equipment is for the benefit of the entire hospital, not one single department.

Also consider the roof space-depending on the physical configuration, roof space could become profit space. IT is a cost center. Placing the network equipment on the roof frees up expensive space and utilizes previously unused space. Consider a small room of at least 8 x 8 feet within the penthouse or roof mechanical space. Should the building entrance room end up there, simply connect roof-mounted systems to that room. There is no need to take more space than you need.

Do not get tied up in communicating space requirements in terms of square footage. Work with the architect, engineer, and facilities team to determine dimensions of obstacle-free rectangles, otherwise the “square footage” may come in a round room with two columns and a window! Remember, square equipment does not fit within a curved wall. Most importantly, when defining space requirements, be firm, be consistent, create and follow standards, and build something that will withstand the test of time well into the future. HBI

Contact Dash at adash@syska.com or 615.663.7967 or Cochran at david.cochran@vanderbilt.edu or 615.322.1400, or visit http://www.syska.com for more information.