@techreport{wu-cpl-schema-02,
    number =    {draft-wu-cpl-schema-02},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-wu-cpl-schema/02/},
    author =    {Xiaotao Wu and Henning Schulzrinne and Jonathan Lennox},
    title =     {{An Extensible Markup Language Schema for Call Processing Language (CPL)}},
    pagetotal = 17,
    year =      2003,
    month =     mar,
    day =       6,
    abstract =  {This document provides an Extensible Markup Language (XML) Schema for the Call Processing Language (CPL). The original CPL specification only provides a Document Type Declaration (DTD) to describe the structure of the language. Compared with XML DTDs, XML schemas have many advantages such as performing stricter type checking, providing pre-defined data types and being able to derive new data types from existing ones. We further split the CPL schema into two parts, one contains elements common to all the telecommunication entities, such as user agents or presence agents. The other contains elements, such as 'proxy', specifically for network servers.},
}