Mapache Server is a MHP Application Server that integrates application content management on Digital Terrestrial Television (DTT) using the protocol MHP (Multimedia Home Platform).

Since year 2010, in Spain, the terrestial television broadcast only will be carried out through digital terrestrial TV. The standard used for this is the DVB-T (Digital Video Broadcasting – Terrestial). This standard allows digital audio and video transmission compressed and this offers the following advantages over the traditional analogue television:

- More television channels, because in the same bandwidth required for the analogue signal can be transmitted several digital channels

- Higher audio and video quality, because the compression formats allow the digital signal broadcast images and sound with high quality

- Additional services, this standard allows emission of data signals in addition to audio and video that provides the possibility that users can run interactive applications from their digital terrestrial receivers

MHP (Multimedia Home Platform)

MHP standard has been fed into international standards bodies such as  ETSI (European Telecommunications Standards Institute). This defines a generic interface between interactive applications provided by DVB and digital broadcast decoders (Set-Top-Box or STB). Main features:

- Service providers will be able to develop interactive applications without depending on particular manufacturers or broadcasters, the only requirement they have to fulfill is to be MHP compliant.

- Enables providers to cover the range of low-end STB to the highest-end, including televisions with integrated DTT and personal computers.

- Enables interoperability between applications and the terminals and between terminals.

DVB has adopted the Java programming language for MHP interactive  applications and has created a lightweight version suitable for broadcast  applications called DVB-J or DVB-Java. MHP specification contains a set of arrangements put in place to ensure the interoperability of equipment in the market.

Objectives

Mapache Server intends to cover the following main objectives:

1. Provide mechanisms for consolidation and integration of data sources and external content

It is necessary to establish the appropriate format of interactive information which will be incorporated into a digital transport stream to enable applications to run in the users decoders (STB).

2. Create an interactive application common repository

Keeps an interactive application store regardless of whether they are emitting or not.

3. Create an application scheduler

According to the applications stored into repository it is necessary to define classifications and time slots by every television channel for programming a scheduled emission.

4. Create an input/output interface

Receives requests for communication of end users and allows both service providers and those responsible for broadcasting properly maintain the system enviroment.

5. Management interactive applications through the return channel of the MHP receivers for data modifications.

The interactive broadcast and Internet access profiles of MHP include support for using a return channel in the MHP receiver to talk to the outside world. Mapache Server uses an interface for bidirectional communication between the receivers and the server for updating applications contents.

Mapache Server Architecture

Mapache Server consists in three main subsystems:

- Syndicator subsystem

- Container subsystem (or Repository)

- Publisher subsystem

In addition to these subsystem, there is another module, the Content Manager, which allows the exchange of information from the container subsystem with the publisher subsystem.

Content Manager and Publisher

Mapache Server provides mechanisnm to publish a set of applications using stream generators.

Content Manager

- Dynamically obtains applications according to programming
- Evaluation changes in broadcast
- Reduced operations
- Data preloading and communication optimization

Publisher system

- Real-time carousel generation
- Communication through basic operations
- Updating files in real time

Recovery system because of erroneous programming

- Generates a new carousel if errors occur due to updatings are produced, meanwhile, continues emitting the original carousel.

Publisher & Content Manager Architecture

Content Manager: Parallel Processing System to updating object carousel.

Publisher: DSM-CC object carousel composition

Container System (Repository)

This system is composed of three layers. Each layer performs work independently to the rest of layers.

Access Layer

  - Data validation
  - Permission check
  - Communication with others systems
  - Compose response messages

Persist Layer

  - Separates access layer of persintence engine
  - Persistence errors management

Persistence Engine

  - Management of major functions of persistent storage
  - Management of binary contents

Syndicator

Features

- This is the only component connected to internet
- Allows the user to access so convenient and easy to update content
- This establishes a communication interface with the DVB-T decoder (STB) through its return channel
- Allows schedule automatic updates of application contents, from external sources, which require a high refresh rate (RSS, images, ...)
- Allows notify users (distribution lists) on changes in the emission of applications and system errors

Technologies

- Spring framework (IoC y AoP)‏
- Quartz (scheduling)‏
- AspectJ
- Log4j (logger)‏
- Struts 2 (webwork 2)‏
- Ajax (Dojo)‏
- This don't define a persistence engine: all necessary information is obtained and sent to Container System

Screenshots

Below are screenshots examples of the syndicator user interface

Main page

Application management

• Allows to user to proactively manage and add applications to cast
• Allows add / modify one by one all the files that compose
• Allows to define tasks for updating content from external sources

Application management

Emission management

• Allows to user to see the profiles time-slots of any channel and applications that are broadcast with these profiles

Emission management