01 March 2010

The Lessons of Wi-Fi #8: You Can Fund Your Wi-Fi Deployment By Rightsizing Your Wired LAN.

By any measure the California State University (CSU) system is enormous, encompassing 23 different campuses, nearly 450,000 students, and 48,000 faculty and staff.

Recently the university system was faced with a massive and potentially hugely expensive wired network refresh to upgrade infrastructure that was approaching the end of its service life. At the same time, the CSU system was experiencing a surge in the demand for network access across all of its campuses. In the absence of a budget for a Wi-Fi solution, which would have allowed one wired port to be simultaneously shared among many users, the IT staff was concerned that the need for Ethernet ports and switches would double.

What would you do in this circumstance? Expand the wired network? Seek additional funds for a wireless initiative? Restrict access to the network?

Those who forget the lessons of Wi-Fi are doomed to repeat them. Lesson #8: you can fund your Wi-Fi deployment by rightsizing your wired LAN.

Cisco suggests that the right solution was to expand the wired network with perhaps a smattering of wireless in lecture halls. Why? In a paper titled True-Sizing the Network, Cisco claims that Ethernet is future proof, more secure, and more reliable than wireless networks. In fact it marginalizes Wi-Fi, relegating it to situations in which Ethernet cannot otherwise be used.

The twisted “true-sizing” message short changes end users because it fails to take into consideration changes in user preferences, markets trends, and technology that have occurred in recent years:

  • iSuppli reports that shipments of laptops surpassed desktops (38.6M vs. 38.5M) in 3 Q 08;
  • Yankee Group estimates that enterprises with no Wi-Fi access will drop from 43% in 2006 to just 3% in 2012;
  • Burton Group states that 802.11n marks the beginning of the end for wired Ethernet as the dominant LAN access technology in the enterprise;
  • Best-in-class Wi-Fi networks sport WPA2 encryption, wireless intrusion detection, policy enforcement firewalls, and FIPS 140-2/Common Criteria/DoD validation - making them equal or more secure than most wired networks.
The best solutions for end users originatefrom understanding how and where they want to use the network, and then designing networks that meet those needs.

Aruba's network rightsizing program defines just such a process - measure wired port utilization, consolidate ports in use into fewer switches, and deploy 802.11n wireless to address mobility needs. Use Wi-Fi everywhere you can, wired networks only where you must. If savings are to be had, the rightsizing analysis process will tease them out. If not, then that will also be made clear. Either way, the network rightsizing analysis will offer insights into network and port utilization that might not be intuitively obvious.

Returning to CSU, what the IT staff decided to do was to obtain more data by measuring wired port usage. What they found surprised them: wired ports across all 23 campuses were consistently underutilized. More than half of the wired ports had passed no packets during the previous six months.

Armed with these data, the team decided to embark on a new approach. Instead of upgrading the entire wired network, something they had historically done every 4-5 years, they looked at the opportunity before them with fresh eyes.

Wi-Fi was determined to be a reliable, low-cost option for delivering pervasive campus connectivity. Several campuses had already deployed some Aruba wireless LAN equipment, mostly for coverage in selected high-usage areas, and San Diego State University had built a relatively large WLAN on their campus. The Aruba WLAN had proven to be highly secure, scalable and reliable. It also allowed for a scaled-back refresh of the wired network, saving money by limiting upgrades only to the wired ports that were actually used.

CSU's IT staff created a database that included every telecommunication room, the number of ports in each room, and the number of those ports that were actively
used. A formula was developed to define the refresh requirements of each of the 23 campuses based on this measurement.

By applying this formula across all 23 campuses, CSU was able to save approximately $30 million by reducing the scale of the wired network refresh and enhancing network access with Aruba’s Wi-Fi solutions.

The CSU system still uses wired networks but they've been rightsized to address actual and projected utilization. Wireless network utilization has risen sharply, because users are taking advantage of the mobility afforded by the expanded 802.11n network. And CSU saved a whopping big chunk of change that can be applied to other programs and opportunities.

Network rightsizing is a proven method of assessing and adjusting your network infrastructure. The California State University rightsizing program is a testament to the validity and value of the rightsizing model.

While the rightsizing mantra is to use wireless wherever you can, wired only where you must, the model makes no presumptions about the right mix of wired and wireless access. Proponents of “true-sizing” maintain no such neutrality. Their bias towards Ethernet marginalizes Wi-Fi, and in so doing deprives end users of the potential cost savings and mobility/efficiency gains that organizations like CSU have obtained.