IPTV architecture and technical challenges

Published: Last Edited:

This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.

IPTV Overview

From Internet TV to IPTV

Although IPTV and Internet TV look very similar, using the same core base of technologies, their aims in delivering video content to the end-users are totally different. IPTV service is delivered over a complex private network which is designed to deliver huge amounts of multicast video traffic with high Quality Of Service, while Internet TV, usually refers to the transport of video streams which are sent over Internet, without any control or guarantee on final delivery from the Internet TV provider, counting on a best effort base. IPTV is usually used to refer to commercial service by Internet providers with close access to the end-user (subscriber) offering a number of TV channels with a similar look to the standard television (1). Internet TV (or IP video) is a quick to market service, with low investment, that is common within portals and websites, offering mostly downloadable video content.

The distinction between IPTV and Internet TV can be clarified according to the following ways. Internet TV use the public Internet to deliver content to users, in contrast to IPTV which uses dedicated private networks that are managed by the provider of IPTV service (2). These private networks are not accessible to Internet users and are located in specific geographical areas, while Internet has no such limitations and Internet TV services can be accessible globally. Sending video content over the public Internet in a best effort way, like Internet TV services, accepts the danger of delay or completely loss of IP packets which are used to carry the video content, resulting to a zero guarantee on a TV viewing experience. In comparison to this, IPTV is delivered over private networking infrastructures with many support mechanisms, controlling the end-to-end delivery of high quality video content [2]. Generally, a dedicated digital set-top box is used to access and decode the video content on IPTV service, while to access Internet TV a PC is almost always necessary, sometimes using specific type of software, for example a dedicated media player which is required to view the video content of a specific Internet TV portal. A huge amount of video content that is delivered over the public Internet is available to the users free of charge, in contrast with IPTV services that are usually fee based, with a monthly subscription model similar to the traditional pay TV service model [2]. Moreover, IPTV providers, provide a great number of different TV channels, TV shows and movies, real-time events like sports and other Video On Demand (VoD) contents as well as a whole concept of TV programs similar with the ones that are delivered by the large media companies.

Introduction To IPTV

Definitions and Standards

Standardization is very important in the telecommunications industry, and especially important in such a complex system as the Internet. The IPTV system is even large and complex, and requires many standards in order to be functional. Generally the IPTV industry tries to standardize itself, mixing old, traditional forums such as the ITU-T with new forums such as the Open IPTV Forum. Although, all have different scopes and slightly different point of view on things, they at least form a finite set of standards - so any service provider, broadcaster and operator looking for IPTV services can select the appropriate ones [3].

The Open IPTV Forum intends to set the options in the end-to-end chain, publishing a set of specifications which describe the architecture at a high level. It does not completely map to the main standard for IPTV with IMS, which comes from the Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN) technical committee of ETSI [3]. The Open IPTV Forum was set up by a group of companies in 2006 in order to create an architecture for the future IPTV services. They published an architecture document in November 2007 that is different from most other standards, because it considers the entire chain of IPTV service, from the end-user to the service provider, including the network in between. The architecture view of the Open IPTV Forum consists of the following five domains:

  • the consumer domain
  • the network provider domain
  • the platform provider domain
  • the IPTV service provider domain
  • the content provider domain.

Sometimes these will overlap, in particular, the content provider, IPTV service provider and the platform provider will occasionally be the same. According to the Open IPTV Forum, the consumer domain is where the IPTV service is consumed. In this case, the normal assumption is that the network provider is a telecom company, with a physical connection to the end-user's systems, being able to deliver IP data packets over that connection. Most of the functions in this domain are standardized in other places, so the Open IPTV Forum avoid to answer the hard questions about how to manage QoS, which ETSI has taken on board [3].

Among many different definitions regarding IPTV, the most known is the official definition approved by the ITU (International telecommunication Union) focus group on IPTV (ITU-T FG IPTV) [2]. According this definition, "IPTV is defined as multimedia services such as television/video/audio/text/graphics/data delivered over Ip based networks managed to provide the required level of quality of service and experience, security, interactivity and reliability"[4]. Moreover IPTV possesses a number of features as: Support for interactive TV, service providers can deliver types of services like standard live TV, high definition TV (HDTV), high speed Internet browsing and interactive games, because of the two-way capabilities of IPTV systems. Time shifting, IPTV in combination with a digital video recorder permits the time shifting of programming content. . Personalization, an end-to-end IPTV system supports bidirectional communications, where end users can decide what they want to watch and when they want to watch it [2]. . Low bandwidth requirements, instead of delivering every channel to every end user, service providers stream only the channel that the end user has requested. Accessible on multiple devices, viewing of IPTV content is not limited to televisions, so the end-users can use their PCs and mobile devices to access IPTV services.

  • http://www.itu.int/ITU-T/IPTV/