Replacing conventional TV distribution systems with LAN technology saves money and prevents low-tech problems such as ghosting, says Colin Farquhar, CEO of Exterity.

Delivering television over a building’s local area network (LAN) is the latest example of the revolution in intelligent building controls - using technology based on Internet protocol (IP) to combine systems such as telephones, data, controls, access control and fire alarms. Ethernet networks are now standard in new buildings, and high-speed networks can be retrofitted to existing ones. This produces a cost-effective, high-bandwidth Internet conduit which provides technological advancements and gives opportunities for integrated systems, more recently of TV and visual display equipment. New-build, high-quality commercial developments are increasingly requiring TV and radio at every desk and throughout the buildings, providing news as it happens as well as corporate information and entertainment in breakout/social areas. Developments in technology mean this can be delivered more cost effectively than by comparable conventional distribution systems.
Technological development
IP networks have radically changed TV systems in buildings. Until recently TV was distributed via an expensive and often cumbersome coaxial cable system. This was difficult to manage and upgrade as well as being unreliable, and could only transmit high-quality pictures over limited distances. It often suffered interference because of poor cable quality or mains electrical supply, causing ghosting and dead zones on transmitted images. It was also, more often than not, installed outside the traditional contractual procurement routes, which exacerbated the problems. The development of a TV to IP gateway interface has enabled terrestrial and satellite services to be plugged directly into a LAN, allowing live broadcast TV and radio to be distributed across a building or campus network. This is a significant development and follows the trend of electronic devices such as telephones, CCTV and building management systems, card readers, and so on, connecting to and communicating via the network.
This so-called network IPTV, whereby all TV, including satellite and analogue feeds, can be streamed directly onto an ethernet network and distributed to any point around the building, does not have any of the problems of the traditional system. As a result, media, financial, leisure and retail companies are increasingly looking to replace their troublesome and fragile coaxial systems.

Application
A network IPTV is increasingly seen as a prerequisite for a variety of end-users for which the provision of TV to desktop is an important and sometimes vital working tool. Many large trading organisations and banking institutions, for example, rely on access to real-time financial news. Without dedicated and reliable access to such information, many would not be able to compete. In terms of corporate TV, an IP system makes it easy to deliver information to staff as well as entertainment in breakout areas.
In the academic world, teaching can be enhanced by making channels available to every PC or display across a campus, providing students with TV and radio channels profiled to suit their interests, home countries and education needs. Implementing digital TV headends for hotels, leisure and event arenas allows local and foreign language channels and radio into hotel guest rooms, common parts and conference areas. Delivering television to patients’ bedsides in hospitals and other care facilities helps to improve the healthcare environment. IPTV is completely scalable, allowing the system to grow as a company expands. It is easy to manage, reliable and relatively simple to maintain, and more robust than the traditional alternative. The advantages in cable and equipment reduction, coupled with vastly superior reception qualities, also simplify procurement and installation procedures. Specialist companies are able to deliver a total solutions package for the delivery of an organisation’s media requirements, including management input and strategic advice, together with all the necessary hardware and software, such as headends, gateways and satellites.

Cost analysis and comparison
The table (see diagram below) shows the typical comparative costs of a coaxial distribution system and an equivalent IP system. The costs are expressed in terms of the supply to 50 PCs to give a representative comparison, since while the IP system theoretically can provide TV signals to every desktop, this would rarely be provided via traditional coaxial cabling as the cost would be prohibitive. Instead, coaxial would normally be fed selectively to certain areas on a floor. The principal differences in the cost for the different sizes of building are a result of the greater vertical distances over which the cable has to be run (assuming that the building height increases with area) and the need for additional amplifiers on the coaxial system to maintain the signal strength in larger buildings. The cost savings are achieved through not having to run dedicated cabling networks with the IP system, as well as the savings attributed to hardware, satellite receivers and modulators, and so on. Comparisons of the conventional and IPTV systems should also take into account space savings within communications cabinets, M&E risers and roof plant areas.
• Colin Farquhar would like to acknowledge and thank Eurosatellites for their help in writing this article.

Cost comparison of coaxial distribution system v IP

	Coax	IP System
100,000 sq ft average
Satellite dishes, local vertical coaxial cabling and satellite switches	£2100	£2100
10 satellite channel headend system (typically what is provided). All channels distributed as free to air channels	£11,000 includes amplifiers, modulators and receivers	£3250, comprising IP encoders / gateways
Vertical distribution to 50 PC positions	£7000	Via network
Horizontal distribution to 50 PC positions	£5000, assuming an average of 30m to each PC	£925 for software license for use on PCs
TOTAL	£25,100	£6275
200,000 sq ft average
Satellite dishes, local vertical coaxial cabling and satellite switches	£3500	£3500
10 satellite channel headend system (typically what is provided) All channels distributed as free to air channels	£13,500 includes amplifiers, modulators and receivers	£3250, comprising IP encoders / gateways
Vertical distribution to 50 PC positions	£12,000	Via network
Horizontal distribution to 50 PC positions	£5000, assuming an average of 30m to each PC	£925 for software license for use on PCs
TOTAL	£34,000	£7675
500,000 sq ft average
Satellite dishes, local vertical coaxial cabling and satellite switches	£4300	£4300
10 satellite channel headend system (typically what is provided) All channels distributed as free to air channels	£15,000 includes amplifiers, modulators and receivers	£3250, comprising IP encoders / gateways
Vertical distribution to 50 PC positions	£14,000	Via network
Horizontal distribution to 50 PC positions	£5000, assuming an average of 30m to each PC	£925 for software licence for use on PCs
TOTAL	£38,300	£8,475