The communications industry is in the process of convergence: data and voice services are provided by one extended network, wireless and wire-line networks are integrated, computers are connected through the big melting pot that is the Internet. So why shouldn't be a technical dictionary to match that convergence of technologies and services? This dictionary includes terms from multiple fields that were separated before. Terms, phrases used across multiple fields can mean many different things. Complicated. We mark every term by its primary fields so that readers can better understand the context and background of the term. Uncomplicated.