VoIP-Forum

An IETF draft outlining the requirements for an authorization framework for SIP:

SIP sessions have needs
for session authentication, authorization and accounting. In order to
perform AAA, SIP entities need to access AAA information (e.g., check
if the password provided by a user is correct or store accounting
records related to a particular session). Rather than collocating a
database with AAA information with every SIP entity in a network, it
is desirable to have a common logical AAA server accessible by all
the SIP entities. SIP entities use a SIP-AAA interface to access this
AAA server. This document outlines some requirements on this SIP-AAA
interface between SIP entities and AAA servers. This document is
intended as a generic document for SIP AAA requirements. It does not
intend to develop a charging and/or billing mechanism for SIP.

• Authentication, Authorization and Accounting Requirements for the Session Initiation Protocol, SIP wg, may 2003

…and some people say that VoIP does not work…

"Edison, NJ, June 16 - Today Vonage, the broadband phone company, reached two significant milestones: activating 30,000 lines and transmitting 30 million calls over its network. "

• Vonage press release

Learn more about the SIP support in Java Jain here:

The
JAIN SIP specification is a general purpose transaction based Java interface to the SIP protocol. It
is rich both semantically and in definition to the SIP protocol. The motivation behind JAIN SIP is
to develop a standard interface to the SIP protocol that can be used independently or by higher
level programming entities and environments. JAIN SIP can be used in multiple ways:

• As a specification for the J2SE platform that enables the development of stand alone user
  agent, proxy and registrar applications.
• A base SIP implementation for a SIP Servlet container that enables the development of
  user agent, proxy and registrar applications in a Servlet based environment.
• A base SIP implementation for an Enterprise JavaBeansâ„¢ (EJBâ„¢) container that enables
  the development of user agent, proxy or registrar applications in an EJB environment.

JAIN SIP provides a standardized interface that can be used by communications developers as a
minimum to support SIP in their applications. The JAIN SIP reference implementation provides a
fully functional SIP implementation that can be used by developers to talk SIP from the Java
environment. The target developer community for JAIN SIP is developers that are familiar with
the SIP protocol and require transactional control over the SIP implementation.

• SIP Specifications and the Javaâ„¢ Platforms -
  The look and feel of SIP! (Acrobat PDF)

This draft, in its third version, is covering requirements for emergency telecommunications.

Effective telecommunications capabilities can be imperative to facilitate immediate recovery operations for serious disaster events, such as, hurricanes, floods, earthquakes, and terrorist attacks. Disasters can happen any time, any place, unexpectedly. Quick response for recovery operations requires immediate access to any public telecommunications capabilities at hand. These capabilities include: conventional telephone, cellular phones, and Internet access via online terminals, IP telephones, and wireless PDAs. The commercial telecommunications infrastructure is rapidly evolving to Internet-based technology. Therefore, the Internet community needs to consider how it can best support emergency management and recovery operations.

• General Requirements for
  Emergency Telecommunication Service

There are many new SIP devices out there and a large set of standards, experimental drafts and proprietary extensions that make interoperability a growing concern. This IETF draft is a starting point in defining a minimum set of core features for new devices attached to an ethernet LAN - wired or wireless:

This informational I-D describes the requirements for SIP telephony devices, based on the deployment experience of large numbers of SIP phones and PC clients using different implementations. The document reviews the generic requirements for SIP telephony devices, the automatic device configuration process, device configuration data and examples for XML configuration data formats. SIP telephony devices are highly complex IP endpoints that speak many Internet protocols, have text, audio and visual interfaces, various input modes, and require functionality targeted at several constituencies: (1) End users, (2) service providers and network administrators and (3) manufacturers and system integrators. The objectives of the requirements are a minimum set of interoperability and multi-vendor supported core features, so as to enable similar ease of purchase, installation and operation as found for standard PCs, analog feature phones or mobile phones.

• 
  SIP Telephony Device Requirements, Configuration and Data