ISM (industrial, scientific and medical) radio bands are license-exempt bands, which were originally reserved internationally for the use of RF energy for industrial, scientific and medical purposes other than communications. However, in recent years these bands have also been shared with license-free error-tolerant communications applications such as Wireless LANs (WLAN) and cordless phones in the 915 MHz, 2.450 GHz, and 5.800 GHz bands. A main usage on these ISM bands is “WiFi.” While “WiFi” is not a technical term, the WiFi Alliance has generally enforced its use to describe only a narrow range of connectivity technologies including wireless local area network (WLAN) based on the IEEE 802.11, which is a set of standards carrying out WLAN communication in the 2.4, 3.6 and 5 GHz frequency bands: ISM band 2.4 GHz (WiFi 802.11b and 802.11g/n) and ISM band 5 GHz (WiFi 802.11a/n/ac).
Recent growth in data traffic driven by mobile applications on smart phone devices, tablets, etc. has continued to strain the capacity of today's networks. Therefore, network operators are increasingly utilizing un-licensed WiFi spectrum to cope with such network congestion. Using unlicensed spectrum is a cost-effective mean to add needed capacity to today's networks and, given the limited availability and high cost of licensed spectrum, this trend is expected to accelerate further as traffic demand continues to grow.
Accordingly, solutions for providing wireless connection switching that is as efficient and seamless as possible are needed.