## 2 Collection of Music Usage Information and Analysis of Structural Limitations  
There has been considerable progress regarding the distribution and settlement of music royalties abroad. DDEX (Digital Data Exchange, LLC, New York, NY, USA), which is an international standard focused on the creation of digital value chain standards to make the exchange of data and information across the music industry more efficient, is one of the best examples [6]. It has been recognized that the DDEX standard is a protocol among interested parties such as copyright holders, music publishers, distributors, metadata companies, music licensing companies, studios, and archives. The DDEX value chain consists of several standard regulations. First, music release notifications and licensing regulations are classified via musical work notification (MWN), musical work licensing (MWL), and letters of direction (LoD). Second, the DDEX standard that communicates information about sales, usage, or revenue generated on a digital music retailer service to the relevant rights owners is the Digital Sales Report Message Suite Standard (DSR), which is known as the Sales and Usage Reporting standard. The DSR standard, which is in a flat-file format, is used to enable the reporting of information regarding the level of sales, usage, and/or revenue generated from the distribution of music or videos, along with information about that music, in order to enable rights owners to pass on royalty payments as appropriate. Third, the Claim Detail Message Suite Standard (CDM) provides three formats that support the owners/administators of musical works and senders of sales and usage reports (usually DSPs) in the exchange of information about claims the owners/administators of musical works make against DSPs with respect to the musical works that appear in the sales and usage reports. Fourth, the Electronic Release Notification Message Suite (ERN) enables record companies or distributors to send data to digital service providers (DSPs) that describe the releases and resources, such as sound recordings and music videos the record company or distributor is making available to the DSP for use on its service, and the terms and conditions under which such releases and resources can be made available to consumers. The most recent version of the ERN to be published is ERN 4.3. Fifth, the metadata rights and recording standard is a regulation between a music licensing company and a recoding company. Finally, the metadata provided in a recoding information notification (RIN) message are an integral part of the operational infrastructure across the music value chain and facilitate the process through which all rights holders and other contributors are properly remunerated. Such metadata can also enable retailers to provide better metadata about their products to consumers, which helps to stimulate search and discovery. Since the DDEX standard was launched in 2006, most music companies and distributors have followed this protocol; however, the situation is different in Korea for several reasons. In Korea, copyright trust service providers have authority over settlement and distribution since they manage the rights delegated by copyright holders, music record producers, or performers. For example, when they carry out the settlement and distribution of music revenues to copyright holders, the copyright trust service provider sums up the music sales volume for a certain period of time (e.g., three months) and provides the data in the form of a report to each copyright holder. In this case, it is difficult to determine the settlement details because the settlement reports do not include accurate information, and there are a number of complex products from OSPs in the reports. In other words, the OSPs calculate the music sales for each user ID (not each music song) and then settle and distribute the music sales and profits to the copyright holders (in this case, copyright trust service providers).