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Green Switches and Routers: What Crayons Can Teach Us About Networking Devices!

- March 26, 2009 - 4 Comments

I look into my daughter’s crayon box and, besides fond memories, I find many shades and hues of the color Green. I look at networks and networking devices (That’s what I do!) and, once again, see many shades and hues of Green. How do you select the best possible Green — the one the drives the most positive environmental impact? With crayons, it’s easy. Look at what you’re drawing and pick just the right Green. My youngest daughter does this with ease in only moments. With networks, it is not nearly so easy or straightforward. You are not trying to accomplish (draw) one thing. You are trying to complete an entire network picture that best represents and properly supports all of your Green IT and business efforts — not just one or even some. So how do you go about picking the right device that best helps you complete the entire picture? The following offers a logical progression of judgment criteria that is aimed at fully evaluating the impact a specific networking device will have on coloring your IT and business the most complete and effective shade of Green. Level 1 — Device Efficiency. Does the networking device consume the least amount of power for the work performed? There is no escaping the fact that electrical devices require power — and cooling. The key is for a device to make the most efficient use of energy required. The efficiency rating of power supplies matter. The use of energy-conserving components matter. The work functions of the device — moving traffic, enforcing security, speeding applications, etc. — matter. Although networking equipment accounts for a small percentage of overall energy costs within an organization, it is still important to pay attention to the potential incremental savings and impact of a networking device that operates efficiently internally.Level 2 — Device Preservation. Does the networing device drive resource savings over its lifetime? Surveys point to organizations retiring their networking devices typically between three and five years of service. That translates to millions of devices and components being sent to recyclers or worse yet, landfills every year. The useful life of hardware platforms and components can be extended in a number of different ways. Internal designs that deliver more consistent operating temperatures and leverage longer lasting components (e.g., ASICs) enable greater longevity of the device internals. Easily upgraded or added sub-systems such as supervisors or service modules enable platforms to adapt to new requirements without a forklift upgrade. And even when the base platform are retired, components that are able to move from one platform to another or function as spares for multiple platforms save not only prior investment, but also the resources required to recycle the old and replace with new. As the services capabilities of networks expand, so too does the role of software within the network. Here, not only does software deliver new services to the network and those people and resources connected to the network, it also serves to prolong the service life of the underlying hardware platform. Hardware designs that are optimized to accept software-based enhancements and accelerate software-drive services serve the business more effectively and efficiently — hastening business reaction, while at the same time, lightening the load on capital expenditures and the environment. Level 3 — Network Efficiency. Does the networking device drive energy and resource savings across the network? Power-over-Ethernet (PoE) is an efficient means of powering networked devices (e.g., IP phones, WLAN access points, security devices). Power originating from a switch-based power supply running at say 92% efficiency (the Catalyst 6500 power supply efficiency rating operating at moderate to heavy loads) beats power delivered through a plug-in power block running at 75% efficiency — or lower if not Energy Star compliant. PoE’s use of one cabling run for both connectivity and power drives even further savings in wiring materials. While these may sound like small savings for each device, multiply this savings by the number of devices that could and should be powered over the network and substantial savings can result. Power and wiring savings only scratch the surface in network consolidation advantages. As the network has continued to expand its service capabilities — moving from connectivity to security to mobility to unified commutations to application acceleration to video delivery — over time, so too has the complexity and demands of the network increased. More services drove the addition of more devices, which drove the need for more energy, more materials, and more high-touch support. A networking device that delivers multiple services and eliminates standalone specialized appliances not only reduces the energy demands of the network, but also the material and support demands as well. Think less boxes built and less service visits made. Level 4 — Resource Management. Does the networking device drive energy efficiency and resource savings beyond the network itself? Global research firm IDC cites that for every dollar spent on server and storage systems, another fifty cents is spent powering and cooling these systems. Networking capabilities that allow full utilization, optimum location, and physical consolidation of your server and storage resources can drive significant savings in the data center. Outside the data center, there is even more savings potential across the IT and business infrastructure. Buildings account for the largest share of the energy bill for organizations. And office space accounts for another large share of operating costs. On the IT side, The Climate Group assigns almost 50% of IT-related energy costs to end user devices (PCs, laptops, phones) and peripherals (printers, scanners, etc.). Networking devices that exercise control over the energy demands of IT end systems and building facilities can have a dramatic impact on not only your organization’s environmental stance, but also your bottom line. (See Cisco EnergyWise.) Networking services (e.g., mobility, security, network virtualization…) that enable optimum use of office space work to reduce real estate requirements and costs. (See Cisco Connected Workplace.) Here, being Green directly translates to being lean.Level 5 — Process Innovation. Does the networking device enable new eco-friendly ways of doing business? In an earlier Ecolibrium blog entry, I outlined what it takes for the network to properly support such Green business practices as telecommuting and remote collaboration. A network that does not deliver a fully productive and satisfactory end user experience will come up short in serving your organization’s need to successfully execute in today’s virtual working environment. Here, the potential for gains — and missed opportunities — is huge. Reduced travel, office space, energy demands, and execution times all result from a network that fosters virtual and sustainable business practices. Extend the possibilities to other networked business functions and processes (e.g., Sales, support, education, supply chain, logistics, partnering…) and you further heighten the Green effect of the network. Networking devices that do not deliver the service capabilities and quality required by these new innovative business processes and practices will not only fail to support your environmental goals, but also your business goals as well.Only when you proceed through all the levels have you completed your evaluation. The truly Green networking device is one that delivers features, capabilities, and benefits across all — not just some — of the Green fronts that matter to your organization. Judging a networking device to be Green is not simply a matter of comparing power supply wattage ratings or packets per second per watt ratios. It takes into account all the many factors that influence not only how Green a specific networking device is, but also how green that device makes your network, your IT infrastructure, your facilities, and your business operations. Call it Absolute Green if you like to think in crayons!

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  1. Hi Mark,Just read your blog. Its very insightful and educational. Really appreciate your effort is making people understand green benefits so well.Regards,Ketaki

  2. Stumbled upon an interesting site,, offers complete Global IT Procurement.

  3. I learned a few things about networking when I went to high school but still many things remained unclear for me. My only hope now is to understand as much as I can from what you guys are posting here.

  4. It is nice to see green building products being used nationally and worldwide, and also the demand for such materials has risen dramatically. We should all be thinking of our planet Earth in any way we can. Just look at the auto industries, bucket trucks, boom trucks, and even crane trucks are going green.