September 1998

BY BRIAN DANIELS & MEI-JEAN GOH

In today's business world, voice mail boasts an installed base of over 10 million mailboxes and 500,000 systems. It is commonplace for people to leave a voice message when a phone call goes unanswered or a line is busy. Somewhat less common is the process of intentionally composing and sending a voice message in the first place, like we do when exchanging e-mail messages. While this option is currently available, it's usually within an enterprise and only for messages between colleagues who share the same PBX or key system, share the same voice mail system, and likely work in the same building. Less common still is the ability to intentionally direct a voice message to someone served by a separate -- and possibly distant -- voice mail system.

In the past, vendors of voice mail equipment have responded to this desire for intersystem communication by devising three approaches to voice message networks:

Proprietary Methods and Protocols
Most major suppliers of voice mail systems offer proprietary ways of delivering voice messages between their systems. But try linking with a voice mail system from another vendor, and you're out of luck.

Standard Analog Voice Message Networking
Audio Messaging Interchange Specification -- Analog (AMIS-A): This is a method that relies on telephone channels for connection.

Standard Digital Voice Message Networking
Audio Messaging Interchange Specification -- Digital (AMIS-D): This method is based on the International Telecommunication Union's (ITU) X.400 series of messaging recommendations.

All in all, networking dispersed voice mail systems has been possible for some time, but the technology has been limited.

Next to leaving a voice message, we could always turn to faxing. Almost as ubiquitous as voice mail, there are 40 million fax machines in the world today spitting out a huge chunk of our communications traffic. This is also taking a huge piece of the communications budget, with fax traffic costing approximately $45 billion each year.

Along comes the Internet revolution. It is currently estimated that 57 million people have access to the Internet. And what's at the top of their lists while on the net? E-mail. There are 188 million electronic mail boxes on the net - and that figure is growing at a rate of 10 percent each year. So, with this Internet explosion, it seemed certain that voice mail and faxes would be relegated to the status of messaging orphans. Not so.

VPIM
Voice Profile for Internet Mail (VPIM) brings voice and fax into the family of Internet messaging technology. Intentional messaging is a good thing: Universal intentional messaging is even better. The Internet exemplifies universality in communications. The Voice Profile has resulted from the desire to build out the global Internet mail facility to include voice and fax message exchanges.

VPIM sprang from the collaboration of voice mail vendors working within the Electronic Messaging Association (EMA), a 700-member trade association of electronic messaging users, equipment vendors, and service suppliers. A working group of vendors showcased operating VPIM prototypes at the EMA's April 1996 annual convention, and followed with product demonstrations the next year. VPIM, based on Internet e-mail standards, is intended to be very much an Internet standard. At this time in 1998, it is on the standards track of the Internet Engineering Task Force (IETF), currently at the level of proposed standard.

Consider the benefits of what VPIM enables: Universal, intentional voice and fax messaging.

Intentional messaging means deliberately leaving someone a message instead of placing a phone call, and then only leaving a message if you can't connect directly with the person called. Intentional messaging elevates voice mail technology from an erstwhile role as an answering machine to the status of effective business tool and productivity expander. Why? Reflect on these business scenarios:

• Jeff wants to let Kelly know that this afternoon's meeting is postponed to four o'clock. He knows that if he calls Kelly, Kelly will likely want to discuss the budget matter. There goes twenty minutes. If he can intentionally deliver a message, Jeff needn't risk losing the twenty minutes.
• Jeff wants to thank the salespeople in the southeast region. A personal message in his own voice is good form. Trouble is, there are two hundred salespeople. Instead, Jeff records a sincere message, addresses it to the southeast distribution list (much the same as he would address a group e-mail) and five minutes later is on his way to the golf course with hours of time saved.
• Before he leaves, Jeff needs to send one last message - to Todd - to remind him of dinner with the fundraisers that evening. Jeff knows that Todd could never find tonight's venue unless he draws Todd a map. Thanks to VPIM's inclusion of fax, he can do just that. From his fax phone, Jeff records a reminder to Todd, and sends it along with a hastily drawn map to Todd's mailbox.

HOW DOES IT WORK?
VPIM is a profile of accepted electronic mail standards and methods used on the Internet, adapted and augmented for the requirements of voice mail. VPIM's immediate foundations are the (Extended) Simple Mail Transfer Protocol (ESMTP) and the Multi-purpose Internet Message Extensions (MIME) specifications. These in turn are built upon the Transport Control Protocol/Internet Protocol infrastructures, which are the backbone of the Internet and many corporate intranets.

SMTP
The Simple Mail Transfer Protocol dates back to the early 1980s, and is the workhorse of electronic messaging on the Internet. It lays out the dialog with which two disparate mail systems converse with one another in order to transfer message content. Originally the message content was (and even now remains), made up of pure and simple text characters. Throughout the 1990s, the protocol has been extended in several ways to accommodate richer messaging forms. These include providing notifications of message delivery, delivery of non-text binary information, and more efficient carriage of large messages. VPIM takes advantage of several extensions.

MIME
The Multi-purpose Internet Message Extensions (MIME) standards recognize the need to include more than simple text within the content of electronic mail. The MIME standards provide mechanisms for including various types of media - text, audio, image, video, and application data such as work processing or spreadsheet documents - within an e-mail. A VPIM voice message is a special type of MIME message.

TIFF
The Voice Profile is more than voice. VPIM enables the Internet exchange of fax messages, alone or accompanied by voice. Here again, VPIM has built upon an accepted standard, in this case, the Tagged Image File Format (TIFF). TIFF has been an accepted standard in desktop publishing for many years, and VPIM has moved a fax-oriented flavor of this, TIFF-F, into the realm of Internet standards. VPIM gives businesses the ability to exchange messages on the Internet in two of the more effective and widely used media.

ADDRESSING A VPIM MESSAGE
The VPIM specification is flexible concerning the way in which a message recipient is addressed. However, certain vendors are adopting a strategy to enable users to address a VPIM message with a mailbox number which is the same as the phone number you would use to dial and talk to the owner of the mailbox. The number could be from an international dialing plan, or a private-network numbering plan.

VPIM carries on the tradition of phone/extension number and voice mailbox address commonality. This applies to private enterprise numbering plans, or public-number plans that are consistent with the ITU's E.164 recommendation or the North American Numbering Plan.

Currently, VPIM servers need to locally store some information to derive the VPIM server address of a message recipient based on the recipient's phone number. However, work is underway within the EMA, IETF, and elsewhere to apply directory technology to voice communications on the Internet. Standards work is already in progress to define schemas (directory organizations) for use in VPIM address resolution. This is working towards an eventual interlocking global grid of public and enterprise directory services that will be a powerful enabler for universal VPIM messaging.

SUMMARY
Voice messaging is a powerful productivity tool, especially when:

• It's done intentionally, and not merely as a resort to an unanswered call.
• It's universal - you can reach people anywhere, inside or outside of your organization.
• It's used just like e-mail.
• It's low cost, and avoids toll charges.
• It combines fax messaging as well.

The vehicle for delivering this powerful tool is the Internet and/or corporate intranets, using messaging standards embodied in the Voice Profile for Internet Mail.

Brian Daniels is a development manager with Northern Telecom's (Nortel) Toronto Multimedia Applications Center. Mei-Jean Goh is a development team leader with this Nortel Enterprise Networks unit. The authors were responsible for the creation of Nortel's Meridian Mail Net Gateway, one of the first commercial products to employ the Voice Profile for Internet Mail standards. Nortel, a leading global provider of communications network solutions, provides network and telecommunications equipment and related services in North America, Caribbean and Latin America, Europe, the Middle East, and Asia/Pacific. Nortel also provides products and services to the telecommunications and cable television industries, businesses, universities, governments and other institutions worldwide.

Nortel, one of the founding companies of the VPIM Workgroup, has pioneered VPIM compliant digital networking between its Meridian Mail and Norstar voice mail systems. Nortel has filed a "Declaration of Compatibility" and a "Declaration of Interoperability" with the Electronic Messaging Association (EMA) in accordance with its procedures for establishing product conformance to VPIM.

Nortel's Meridian Mail Net Gateway and Norstar Voice Mail allow for VPIM compliant digital transmission of voice mail messages across the Internet or across a corporation's intranet or wide-area network (WAN). Nortel will support VPIM in future releases of Meridian Mail and Norstar Voice Mail, and plans to utilize the technology as the preferred way to network Nortel messaging systems.

Nortel continues to work aggressively with the VPIM Workgroup to establish VPIM as an industry standard and to ensure that VPIM completes the Internet standards track. Interoperability testing has already been completed with several vendors and Nortel is committed to working with all vendors to achieve compatibility between all messaging systems.

• Send and receive voice and fax messages on private intranet IP networks or the Internet.
• Forward voice and fax messages.
• Reply to voice and fax messages.
• Multiple recipients for message.
• Tag messages sent to be private.
• Set priority of messages sent.
• Request and receive delivery and non-delivery status notifications.
• Request and receive disposition status notifications (message has been heard or seen).
• Sender's spoken name accompanies message.
• Sender's personal electronic business card accompanies message.
• Message may contain multiple voice and fax attachments.