Cisco Cisco Videoscape Voyager Vantage Software Development Kit (SDK) 설치 가이드

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TP-00091-01 
 
 
 
Metadata Extraction Tool Description 
 
Metadata Extraction Tool Description 
The Metadata Delivery System (MDS) is the source of all Arris VOD metadata for 
the customer-premises equipment (CPE). This includes providing all additions, 
updates, and deletions for all required metadata elements.  
Upon startup, the MDS reads and caches several predefined configuration files. 
These files contain the TCP IP address and port of the Arris VOD publisher, the 
SQLite database schema details, and the Arris-to-Media Suite database field 
mappings. Subsequently, the MDS will utilize the Arris VOD publisher IP address 
and port, retrieved from the configuration file, to establish a persistent TCP 
connection with the publisher. While this connection's underlying network protocol 
is TCP, the MDS will accommodate an HTTP-like XML-based application layer 
publisher/subscriber protocol, as set forth by the Arris VOD publisher 
specifications. Accordingly, the MDS will issue a subscription request to the 
publisher that contains the list of metadata-on-demand (MOD) names for which it 
wants to register (receive updates). 
Upon successful subscription, the VOD publisher returns a complete list of metadata 
for each MOD name specified by the MDS. After receiving this initial complete list of 
metadata, all subsequent data received from the Arris VOD publisher will be 
updates -- additions, modifications, and deletions. Upon successful retrieval of the 
complete list of MOD metadata or any metadata modifications, the MDS will parse 
the recovered stream. Initially, this entails the separation of the HTTP-like headers 
from the actual XML message content. Once the XML message is identified and 
secured, it is also parsed so as to acquire those metadata elements to be transformed 
into MediaSuite-compatible entities.  
Next, and in accordance with the database schema and field mappings contained in 
the aforementioned configuration files, the resultant MediaSuite entities will be 
inserted into an SQLite database file. Using the current DNCS BFS server API, this 
file will then be placed on an in-band BFS carousel to be consumed by the CPE 
devices. 
In addition to the delivery of the database files, a category hierarchy file (CHF), and 
a summary file (SF) are also placed on an in-band and out-of-band BFS carousel. The 
CHF should contain all of the categories to be encountered by the client during 
metadata processing, while the SF will contain information describing the previously 
created SQLite database files. The following diagram depicts the entire process flow 
required by the MDS portion of the MET subsystem.