(0.62–0.93 mi). This was the case when only the 2100 MHz band was being used, however with the growing use of lower-frequency bands (such as 850 and 900 MHz) this is no longer so. This has led to increasing rollout of the lower-band networks by operators since 2006. Even with current technologies and low-band UMTS, telephony and data over UMTS requires more power than on comparable GSM networks. Apple Inc. cited UMTS power consumption as the reason that the first generation iPhone only supported EDGE. Their release of the iPhone 3G quotes talk time on UMTS as half that available when the handset is set to use GSM. Other manufacturers indicate different battery lifetime for UMTS mode compared to GSM mode as well. As battery and network technology improve, this issue is diminishing. Security issues As early as 2008, it was known that carrier networks can be used to surreptitiously gather user location information. In August 2014, the Washington Post reported on widespread marketing of surveillance systems using Signalling System No. 7 (SS7) protocols to locate callers anywhere in the world. In December 2014, news broke that SS7's very own functions can be repurposed for surveillance, because of its lax security, in order to listen to calls in real time or to record encrypted calls and texts for later decryption, or to defraud users and cellular carriers. Deutsche Telekom and Vodafone declared the same day that they had fixed gaps in their networks, but that the problem is global and can only be fixed with a telecommunication system-wide solution. Releases The evolution of UMTS progresses according to planned releases. Each release is designed to introduce new features and improve upon existing ones. Release '99 Bearer services 64 kbit/s circuit switch 384 kbit/s packet switched Location services Call service: compatible with Global System for Mobile Communications (GSM), based on Universal Subscriber Identity Module (USIM) Voice quality featuresTandem Free Operation Frequency 2.1 GHz Release 4 Edge radio Multimedia messaging MExE (Mobile Execution Environment) Improved location services IP Multimedia Services (IMS) TD-SCDMA (UTRA-TDD 1.28 Mcps low chip rate) Release 5 IP Multimedia Subsystem (IMS) IPv6, IP transport in UTRAN Improvements in GERAN, MExE, etc. HSDPA Release 6 WLAN integration Multimedia broadcast and multicast Improvements in IMS HSUPA Fractional DPCH Release 7 Enhanced L2 64 QAM, MIMO Voice over HSPA CPCcontinuous packet connectivity FRLCFlexible RLC Release 8 Dual-Cell HSDPA Release 9 Dual-Cell HSUPA See