In MHP, several different types of packages are intertwined into a hybrid, the main packages are pJava, DAVIC, DVB, JavaTV, and Havi. The Personal Java Standard Pack is a standard package based on pJava 1.1.8 defined by Sun Microsystems. DVB is a package provided by the DVB/MHP Technical Committee, which is primarily a supplement to the DAVIC package and some Java standard packages. Many of these packages have serious design flaws. For example, the JavaTV package does not have much effect relative to the DAVIC/DVB package. The JavaTV package is mainly provided by the JavaTV Consortium. Sun Systems has its intellectual property. Its content covers almost all DAVIC and DVB packages, but it does not have an obvious resource management model. If several applications need the same at the same time, Different implementation models have different results when one resource is used.
The Havi graphics package also has its drawbacks. It is based on java.awt and can be used to reconstruct a two-dimensional graphics widget system similar to AWT using AWT's lightweight component. However, because it can not completely replace AWT, it caused the situation that two graphics packages coexist. In addition, the DVB-HTML standard is not very successful. In the formation of the MHP standard, there has been a fierce debate about the definition of HTML.
The problems in the MHP have been recognized, and its 1.0 more genuine (1.0.1) has put forward more than 1,000 comments on the modification and reconstruction of the package, and its test package has been delayed, which explains Its complexity.
Of course, DVB/MHP also has many merits. There are two main points: one is the identification and operation mode of the application after downloading; the second is the application data authentication, and the authority management of the internal resources of the set-top box and the application of the X.509 certificate. , which makes it consistent with the authentication of the Internet transmission data.