Over the past decade, wired network connectivity has jumped from 100Mbit/s to 10,000Mbit/s (or 10Gbit/s), finally laying to rest the argument that bandwidth consumption is an obstacle to IP video solutions. With today's advances in bandwidth capacity and compression technology, many security professionals are marrying these complementary trends to successfully implement network cameras and increase deployment of high-definition imagery. But as more users push for wireless access to their surveillance systems, a new question arises as to whether mobile networks can support this demand.
Currently 3G cellular networks offer enough bandwidth to stream VGA video signals at reduced frame rates which, in some cases, is exactly what the surveillance application requires. Over the past year, however, HDTV surveillance video has gained tremendous market acceptance which has driven quality expectations to a level that is not attainable with existing 3G mobile network implementations.
Though AT&T and Verizon continue to stage media wars about who has the better 3G network, it's clear that 4G cellular networks hold the key to greater bandwidth capacity and more efficient compression algorithms for mobile video. We're now reaching the point where mobile connectivity can certainly deliver sufficient bandwidth to support a variety of video applications. This article will explain the technology standards being implemented in 4G networks and provide insight into how they could affect the security industry.
The battle for standards supremacy in wireless networks
At the turn of the decade, the battle lines were drawn for control over the fourth generation in cellular networks - also known as 4G. Worldwide Interoperability for Microwave Access, or WiMAX, was introduced in 2001 as a technology for last-mile implementations of broadband wireless access. Originally scoped as an alternative to DSL and cable, manufactures started integrating this technology directly into computing devices such as mobile phones and laptops. Sprint was the first telecommunications company in United States to build a 4G mobile network based on WiMAX technology.
Four years later, the Third Generation Partnership Project (3GPP) introduced a competing standard - Long Term Evolution (LTE). LTE is an extension of existing 3G mobile networks used today -- which is why some people don't consider it a true 4G mobile network. Despite its perceived lack of next-generation innovation, LTE assumed the technology leadership role because of its current higher-speed capabilities. More than 40 telecommunications companies worldwide, including AT&T and Verizon, have chosen LTE for their 4G mobile networks. This widespread deployment has made LTE the de facto standard.
The evolution of mobile bandwidth
In today's 3G wireless networks, mobile download speeds generally range between 500Kbit/s to 1.5Mbit/s. In cities like Seattle and Philadelphia where WiMAX is offered, however, customers are seeing bandwidth speeds approaching 6Mbit/s. At these data rates, you can successfully deploy video applications, but only if you're willing to sacrifice image quality and/or frame rate. For instance, a 720p video stream using H.264 compression might consume 4-8Mbit/s, which puts it out of reach for 3G networks while fully consuming bandwidth capacity for WiMAX networks.
LTE, on the other hand, specifies download speeds of at least 100Mbit/s, which is comparable to existing local area networks. More importantly for video applications, LTE specifies upload speeds of at least 50Mbit/s. These distinctions become essential in any number of surveillance applications. For example, upload speeds are important for supporting installations where cameras are located at a remote site and send video to a centralized recorder. If operators are viewing video remotely on their handheld displays, then download speeds are a critical consideration. In either case, LTE offers significant bandwidth improvements over WiMAX and traditional 3G wireless networks and enables the delivery of higher-quality video feeds which in turn give the security professional better situational awareness.