Frequently Asked Questions
WLAN is not used for critical communications…?
People are sometimes surprised, when they hear that WLAN is used in numerous business and even life critical applications and use expands all the time. Some examples:
- Hospital clinical information systems (point of care with laptop on cart, PDAs, life critical patient monitors, personnel safety and location)
- Large warehouses and logistics operations (forklift terminals, handheld terminals)
- Large enterprises use increasingly Voice over WLAN (Vo-Fi) communications. VoIP is very sensitive to network errors. Enterprises as well are moving to all wireless offices and achieve huge savings in LAN infra investments and maintenance.
- Airport staff operative communications (gate communications, handheld devices with service crews, plane fueling staff, catering)
- Harbors (vehicle and handheld terminals at cranes, straddle carriers, trucks, RFID gate readers)
- On the more exotic side, for example mining machinery often is remotely operated over WLAN
Is it safe to use WLAN for business information?
Security used to be the top concern in WLAN networks and a lot of R&D has been put in to solve this. As of today, properly configured and planned WLAN networks are very safe. WPA2 encryption gives excellent security for the over the air communications. This may be complemented further with other technologies like VPNs and Wireless Intrusion Detection and Prevention Systems (WIDPS).
How can you promise a SLA (service level agreement) for WLAN network? What does the SLA promise mean?
SLA means that service quality is measured and reported continuously in a manner that that really reflects end user experience and network is also proactively maintained and optimized to keep this predefined quality level. Network optimization may mean network equipment parameter changes, cleaning and regulating local radio spectrum use, adding or moving equipment, changing WLAN antenna types, redirecting antennas, getting faults fixed in network elements, replacing equipment having a degrading performance over time and selecting optimal client devices to be used in the network. It is unfortunate but regularly WLAN networking equipment have software faults that prevent reliable and smooth operation. Detecting these is impossible without proper performance management solution.
I have already a top class WLAN controller and wireless management software with it? Why would I need something else?
If your network end users are continuously satisfied for the WLAN services or possible intermittent connection problems in network do not bother, you likely don't need else. If you operate WLAN in critical environment, you usually have to be able to maintain network performance constantly at the predefined high level. Network performance management and application service level management (SLA) functionalities are missing from WLAN controllers. They provide no visibility to service quality from end user perspective. As a result, maintenance and fault process is most often triggered by end user fault reports after the problem has already emerged. Every wireless and wired network needs optimization and maintenance. Without continuous visibility to end-to-end network performance, network optimization is difficult or even impossible. 7signal Sapphire complements WLAN controllers, WLAN management software and LAN/WAN element manager solutions in business critical networks by adding the missing performance and service level management functionalities.
How does 7signal Sapphire differ from Wireless Intrusion and Detection (WIDPS) products, like AirMagnet, AirDefense and AirTight Enterprise products?
One focuses on security and another on network performance and service levels. WIDPS solutions focus on security and remote troubleshooting functionalities. 7signal Sapphire Wireless Quality Advancement (WQA) solutions focus on end user experience, network performance in wireless and wired networks, SLA management. 7signal Sapphire uses highly advanced Eye stations with a large coverage and additional capabilities compared to standard access point sensors with omni-directional antennas. See 7signal site product pages for a more accurate comparison of capabilities.
Can I use 7signal Sapphire to monitor wireless network of different vendors?
Yes, 7signal Sapphire is vendor agnostic/neutral. It supports different vendors and different equipment generations.
Does 7signal Sapphire automatically correct problems in the network?
7signal Sapphire or no other system is able to correct severe problems in the network by itself. These may emerge in the form of interfering devices, lacking coverage, lacking capacity, hardware faults in access points or antennas, faults in end user devices, software faults in network equipment (WLAN/LAN/WAN) and configuration errors to name a few. Common interfering devices include uncoordinated neighbor WLANs, Bluetooth devices, wireless video cameras, baby monitors, microwave ovens and motion detectors. 802.11e (QoS) and some related WLAN vendor specific implementations provide a capability to allocate different amount of resources for different clients and applications. While this give a little bit more room for critical clients/applications to breath, it does not impact to overall capacity at all. In worst case, lower priority clients get practically no service at all. Sapphire enables proactive WLAN network management that is necessary to let professional network managers to take care of the above mentioned issues.
I have a "power boost" function in my access points. Neighbor access point increases power if one fails. Isn't that enough?
If the initial network plan is done with necessary overlap with access point coverage areas and initial access point power levels have been reduced about 6 dB (from 20 dBm to 14 dBm), then this strategy might provide some help for a case where access point fails completely. However, total access point equipment failure is not the typical reason for network issues and power boost cures only that. Reasons reside more often in radio environment, network parameters and also software faults in network equipment. For this reason, this significant overlapping RF coverage strategy might not be worth of investment. It is important also to remember that even though access point output power increase improves client receiving levels, it does nothing for client signal levels at access point.
I have automatic RF channel allocation function in my controller. Is it sufficient?
Automatic channel control functionalities have turned to underperform in current implementations. This feature provides some benefits in a case there is only one or few clear interferers that may be avoided by channel a change. Local optimization resulting from the current implementation of this feature does not often deliver expected outcome. One automatic change triggers another change in the neighbor access point and this process continues. Access points in the possible neighbor network, having the same feature, start its own process. This leads to an uncontrolled and harmful "oscillation" in network settings. 7signal is experience has shown that network managers with proper tools do a superior job compared to current automated implementations.
I have 802.11n, isn't that enough?
802.11n does provide more throughput and capacity. As well coverage is improved if client devices support MIMO. 802.11n does not provide any additional capability to manage network performance.
Cisco announced CleanAir technology recently. How does that relate to 7signal Sapphire?
It is very good to see that WLAN quality aspects start to gain attention! Cisco CleanAir is a spectrum analyzer and vector signal analyzer capability integrated to a new access point model. It measures radio spectrum, when the access point is not transmitting. It also indentifies sources of non-WLAN interference and prefers using channels that have less interference. Functionally new things are improved automatic radio channel selection algorithm and identification for the source and location of interferer (microwave oven, baby monitor, Bluetooth, etc). As opposed to 7signal, Cisco CleanAir does not provide any visibility on what kind of service quality network provides for end users, it cannot monitor SLA levels and it does not cover other than radio connection part. It also requires all access points to be replaced in the network and does not work in multivendor environments. 7signal Sapphire has also spectrum analysis capability integrated into it. 7signal is already looking for an opportunity to see impact of CleanAir in a live network. 7signal Sapphire performance metrics before and after the roll out of CleanAir access points will tell the difference in end user experience in a live network.
How much does 7signal Sapphire cost?
Compared to Enterprise WLAN network equipment without installation labor costs, cost of Sapphire WQA is about 15-20%. When installation labor is included, additional investment is clearly smaller, typically below 10%. Only one Sapphire Eye is needed for every 6-12 access points, so the roll out is fast. With new networks, avoiding the need for unnecessary overlapping coverage (= more access points just in case one fails), deploying 7signal Sapphire provides savings already in first investment by decreasing the amount of needed access points and associated controllers and software licenses. Efficiency of network managers is significantly improved with centralized and remote troubleshooting capability. This alone results a payback time of 6-12 months. The biggest benefit of course is that people can perform their work as planned. The cost of downtime or lacking speed may provide almost instant payback.
Why have large Enterprise WLAN vendors not implemented performance and SLA management functionalities for their products already?
We have been asked this many times and we have no clear answer. In wired (LAN/WAN) networks there are already solutions in place from vendors like Netscout and Shunra. It seems obvious that next the weakest link of all, the radio connection, needs to be included as well. It seems that general focus has been on security and enhancing the maximum throughput over radio connection. It also seems that now the focus is turning more towards WLAN performance and capability to deliver continuously good user experience. There are several studies (for example from Aberdeen group) indicating that network performance and efficient management of resources are the most urgent issues to solve today.
My company operates on several sites, some of them overseas. Can I use 7signal Sapphire for centralized monitoring?
7signal Sapphire supports fully managed service provider environments, operator networks and large enterprise use. One central Carat server can handle multi location networks and isolate completely different organizations. One Carat is sufficient even for very large deployments, typically 1000-2000 Sapphire Eye stations, each measuring 6-12 access points.
Why do I need 7signal when I already have management tools from Cisco, Aruba, Air Defense or Air Magnet?
7signal provides customers visibility into the "last mile" of the network connection. The visibility between the Access Point and Clients provides invaluable performance information that no other solution can provide. Essential network data metrics are provided such as end user experience, data throughput, packet loss, delay, jitter and application server connection success rates that are not available from other vendors in the industry. This data is reported against predefined SLA targets that allow network operations to quickly detect bottlenecks. The 7signal Wireless Optimization solution complements your existing management tools in the areas where they lack capabilities. In essence, 7signal adds end user performance optimization functionality to your network management platform.
I just invested in upgrading my Cisco WCS to NCS Prime. What additional value does 7signal provide?
7signal focuses on optimizing existing wireless network infrastructures and adds additional capability and functionality that is currently missing. Many vendors offer a single management platform that makes it easier to configure wired and wireless networks together. However, NCS prime for example, offers limited functionality and does not provide an end user view. Part of the NCS Prime solution is Cisco CleanAir that requires access points with spectrum analyzer functionality and a separate license for activating. Cisco CleanAir is only a physical layer (Layer 1) spectrum analyzer, used mainly for troubleshooting purposes after end users report problems.
7signal Wireless Optimization extends visibility beyond the access point and radio layer, covering all layers (1-7) and provides critical metrics from an end user perspective that other vendor solutions cannot provide. With 7signal, performance optimization starts from making sure that end users get required bandwidth and quality (layer 4-7). If this is not met, then network specialists can focus on lower layers to identify bottlenecks and remove them.
Why do I need 7signal to improve my wireless when I have the support of my supplier?
Currently available Enterprise Grade WLAN solutions have been architected to support usage scenarios where network performance and capacity are not pushing limits. Neither WLAN vendors nor managed service providers have the capability to go beyond current levels without accurate data of network state and bottlenecks limiting its operation. 7signal Wireless Optimization solution provides data that has never been available from other vendor solutions. This information is essential in optimizing and maintaining the highest levels of service for end users and protecting network investments. For this reason, the list of 7signal customers includes WLAN equipment vendors, mobile/Wi-Fi network operators, managed service providers, enterprises, hospitals, universities, logistics and other organizations where current levels of service are not sufficient.
What makes 7signal different from other solutions available from other vendors?
7signal provides customers relevant data from a client perspective as well as overall wireless metrics that have never been available to customers. The 7signal Sapphire Optimization solution affords customer the ability to have continuous visibility, reporting and alarming capabilities when key SLA's are not being met in critical areas of operations. With 7signal, this can be achieved without deploying any additional software to end user devices, without interfering with the operation of the WLAN network itself or replacing the whole network.
Is 7signal a solution I will need to deploy throughout my entire wireless environment?
It depends on the usage and nature of the network, but usually this is not the case. 7signal's Wireless Optimization solution is usually deployed to areas with critical applications -- high dynamics in traffic volumes, complex environments where network managers do not have full control of the used WLAN spectrum, or where there is a large variety in models and capabilities of used end user devices. Thorough visibility in critical areas helps network managers understand network, client and wireless application behavior. This information can even be leveraged in other less critical areas where 7signal is not deployed.