Nokia Siemens has introduced its latest technology to help mobile networks cope with rising levels of signalling traffic, much of it generated by ‘chatty’ applications such as social updates, which constantly poll the base station.
Introduced at this week’s CTIA event in Las Vegas, the new software is an addition to NSN’s Liquid Radio W-CDMA Software Suite. It centers on a tool called fast dormancy profiling, which enables the network to identify older handset models, and eliminate the excessive signalling they often create, because they have not been fitted with modern features to mitigate this.
There are two other main technologies in play. With Fast Cell PCH Switching, the network ‘learns’ how specific smartphones are using services and shortcuts the signaling process to reduce the level of activity, and the burden on the RNC (radio network controller). And High Speed Cell FACH enables networks to support more smartphones by decreasing signaling load between the RNC, base station and terminal.
According to head of portfolio marketing Phil Twist, the new Liquid Radio capabilities help the network adapt to disruptions such as a handset running out of battery, and then creating a rush of signalling to reconnect. Such actions can reduce the ‘signalling storm’ as much as tenfold, freeing up network capacity for applications and reducing operating costs.
NSN has tended to grasp the high ground in this area, and took the lead, back in 2010, in highlighting that an overload of signalling could be as degrading to mobile performance as data overload. It has developed a range of features to address the issue, even extending its tools to machine-to-machine connections a couple of years ago. Signalling overloads have caused a string of highly publicized network outages at carriers like Verizon and NTT Docomo, which increased the pressure on vendors to find solutions, and also on software providers to make their applications more forgiving of mobile systems.
“When people use smartphones, they stay connected to mobile broadband networks for longer periods of time and use a wider variety of services,” said Thorsten Robrecht, VP portfolio management at Nokia Siemens Networks. “As data traffic grows, there is a huge rise in signaling between smartphones and core networks to keep services active. Coping with this signaling is critical to maintain network services and deliver an outstanding smartphone experience for mobile broadband customers.”
Late last year, Ericsson and Qualcomm demonstrated their own approach to signalling storms, conducting network and chipset tests on three emerging 3GPP standards in this area – HS FACH, E-FACH and UE DRX. Together, this trio will help reduce signalling traffic and improve the user experience.
Up to 60% of data bursts in mobile networks are less than one kilobyte in size, Ericsson said at the time. The three standards are designed to handle these small bursts more efficiently. The first two improve downlink and uplink respectively, reducing signalling, improving bandwidth capacity and providing a faster experience for the end user.The UE DRX feature saves device battery power. Together, they can boost response time by two to four times.