HTTP/1.1 200 OK Date: Tue, 09 Apr 2002 11:59:49 GMT Server: Apache/1.3.20 (Unix) Last-Modified: Thu, 02 Jun 1994 22:00:00 GMT ETag: "3ddb56-b524-2dee5660" Accept-Ranges: bytes Content-Length: 46372 Connection: close Content-Type: text/plain Network Working Group Greg Vaudreuil Internet Draft Tigon Corporation Expires: 10/25/94 April 25, 1994 MIME/ESMTP Profile for Voice Messaging ToDo: 1) Fix Bibliography, Make References in Text Status of this Memo This document is an Internet Draft. Internet Drafts are working documents of the Internet Engineering Task Force (IETF), its Areas, and its Working Groups. Note that other groups may also distribute working documents as Internet Drafts. Internet Drafts are valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet Drafts as reference material or to cite them other than as a "work in progress". 1.Abstract A class of special purpose computers have evolved to provide voice messaging services. These machines generally interface to a telephone switch and provide call answering and voice messaging services. Traditionally messages sent to a non-local machine are transported using analog networking protocols based on DTMF signaling and analog voice playback. As the demand for networking increases, there is a need for a standard high quality digital protocol to interconnect these machines. The following document is a profile of the Internet standard MIME and EXMTP protocols for use as a digital voice networking protocol. This profile is based on an earlier effort in the Audio Message Interchange Specification (AMIS) group to define a voice messaging protocol based on X.400 technology. This protocol is intended to satisfy the user requirements statement from that earlier work with the industry standard ESMTP/MIME mail protocol infrastructures already used within corporate internets. This profile will be called the voice profile in this document. 2.Scope and Design Goals MIME is the Internet multipurpose, multimedia messaging standard. This document explicitly recognizes these capabilities and provides a mechanism for the exchange of various messaging technologies including voice and facsimile. It is not a goal to make the interoperation of the earlier X.400 based AMIS-Digital and this profile possible by the use of a standard X.400 to MIME gateway. While the message encodings and messages semantics are similar, the addressing and routing are not. The X.400 based AMIS-Digital addressing format is Internet Draft Voice Profile April 25, 1994 sufficiently customized that it cannot be mapped to the RFC 822 mail format in the standard manner. The voice profile is necessarily incompatible because it is intended to use the standard TCP/IP mail addressing formats. It is a goal of this effort to make as few protocol changes to the existing Internet mail protocols as possible while satisfying the user requirements for Voice Networking. This goal is motivated by the desire to increase the accessibility to digital messaging by enabling the use of proven existing networking software for rapid development. Using the native capabilities of the internet mail system most user requirements listed in the appendix can be met. This specification is intended for use on a TCP/IP network. While it is possible to use these protocols for simple point to point networking, the specification is robust enough to be used in an environment such as the global Internet with installed base gateways which do not understand MIME. It is expected that a messaging system will be managed by a system administrator who can perform TCP/IP network configuration. When using facsimile or multiple voice encodings, it is expected that the system administrator will maintain a list of the capabilities of the networked mail machines to reduce the sending of undeliverable messages due to lack of feature support. This specification is a profile of the relevant TCP/IP Internet protocols. These technologies, as well as the specifications for the internet mail protocols are defined in the Request for Comment (RFC) document series. This series documents the standards as well as the lore of the TCP/IP protocol suite. This document should be read with the following RFC documents: RFC 821, the Simple Mail Transport Protocol, RFC 822, the Standard for the format of ARPA Internet Messages, RFC 1521 and RFC 1522, the Multipurpose Internet Mail Extensions, RFC 1425 and RFC 1427, Extensions to the SMTP protocol (ESMTP), and RFC 882 and RFC 883, the Domain Name System. Where additional functionality is needed, it will be defined in this document or in an appendix. 3.Protocol Restrictions The number of recipients per message is not limited by this protocol. Where possible implementations should not restrict the number of recipients that can be received in a single message. The maximum message length is not limited by this protocol. Implementors should understand that some machines will be unable to accept excessively long messages. A mechanism is defined in the RFC 1425 ESMTP extensions to declare the maximum message size supported. (Units are in bytes, not minutes which can vary by encoding format.) 4.Framework for the voice profile Vaudreuil Expires 10/25/94 [Page 2] Internet Draft Voice Profile April 25, 1994 This document specifies a profile of the TCP/IP multi-media messaging protocols for use by special purpose voice processing platforms. These platforms are not general purpose computers and often do not have facilities normally associated with an Internet Email capable computer. The following are typical restrictions imposed by a voice messaging platform. 1) Text messages are not normally received and often cannot be displayed or viewed in the normal fashion. They can be processed only via advanced text-to-speech or text-to-fax features not currently present in these machines. 2) Voice mail machines act as an integrated Message Transfer Agent and a User Agent. The VM is responsible for final delivery and there is no forwarding of messages. RFC 822 header fields have limited use in the context of the simple messaging features currently deployed. 3) Voice mail message stores are generally not capable of preserving the full semantics of an Internet Message. As such, use of a VM for general message forwarding and gatewaying is not supported. Storage of Received lines and Message-ID may be be limited. 4) Internet style mailing lists are not generally supported. Distribution lists are implemented as local alias lists. 5) There is generally no human operator. Error reports must be machine parsable so helpful responses can be given to users whose only access mechanism is voice. 6) The system user names are limited to 16 or fewer numeric characters. Vaudreuil Expires 10/25/94 [Page 3] Internet Draft Voice Profile April 25, 1994 5.Message Format Profile The voice profile was written to be based on and be consistent with the TCP/IP Protocol Suite as amended to support specific services not provided in the TCP/IP protocol suite. This section is intended to be an overview of the necessary protocols and a profile of the applicable protocols as applied to the voice messaging environment. 5.1. Message Addressing Formats RFC 822 and SMTP addressing use the domain name system. This naming system has two components, the local part, used for username or mailbox identification and the host part, used for machine or node identification. These two components are separated by the commercial @ symbol. The local part is an ASCII string uniquely identifying a mailbox on a destination system. It is required to be unique with the system of networked voice mail machines. The local part is defined to be a printable string containing the mailbox number of the originator or a recipient. Administration of this number space is expected to be conformant with national or corporate telephone numbering plans. The domain part of the address is a hierarchical global name for all machines. In the domain name system, a name is registered with the Internet Assigned Number Authority (IANA). The IANA may delegate the management of a branch of the naming space to be administered by a company or service provider. For participation in the international Internet network, or for integration within a corporate internet, each voice mail (VM) machine is required to be given a unique domain name. For example, a compliant message may be 2145551212@mycompany.com. It should be noted that while the example mailbox address is based on the North American Numbering Plan any other corporate numbering plan can be used. The use of the domain naming system should be transparent to the user. It is the responsibility of the VM to translate the dialed address to the fully qualified domain name (FQDN). The mapping of dialed address to VM destination is generally accomplished through implementation specific means. Mapping of the FQDN to a specific network destination is generally performed by the Domain Name System. For networks with a small number of machines, the use of a locally maintained host table database can be used as a simpler alternative. Special addresses are provided for compatibility with the conventions of the Internet mail system and to facilitate testing. These addresses do not use numeric local addresses both to conform to current Internet practice and to avoid conflict with existing numeric addressing plans. Vaudreuil Expires 10/25/94 [Page 4] Internet Draft Voice Profile April 25, 1994 Postmaster@domain By convention, a special mailbox named postmaster should exist on all systems. This address is used for diagnostics and should be checked regularly by the system manager. This mailbox is particularly likely to receive text messages. This is not normal on a voice processing platform and the specific handling of these messages is up to specific implementation. Loopback@domain A special mailbox name named "loopback" should be designated for loopback testing. All messages sent to this mailbox must be returned back to the sender address. Because VMs do not use alpha-numeric addresses, this will not conflict with any internal numbering plan. Internal to VM, a specific numeric address for DTMF entry can be mapped to "loopback". Note that the loopback address can be abused to route messages through a third party VM to avoid toll charges. It is recommended that the loopback feature be disabled except when testing the networking between machines. 5.2. Message Header Fields Internet messages contain a header information block. This header block contains information required to identify the sender, the list of recipients, the message send time and other information intended for user presentation. Except for specialized gateway and mailing list cases, headers are not used to indicate delivery options for the transport of messages. RFC 822 defines a set of standard message header fields. This set is extended in several RFCs. Note that the specific order of header lines is not specified. The order cannot be expected to be preserved when sent through intermediate gateways. The following header fields must be supported. From The originators fully qualified domain address. (This is a mailbox number followed by the fully qualified domain name.) The user listed in this field should be presented in the voice message envelope as the originator of the message. Example: 2145551212@mycompany.com Vaudreuil Expires 10/25/94 [Page 5] Internet Draft Voice Profile April 25, 1994 To The recipient's fully qualified domain address. There may be one or more To: fields in any message. All recipients of a message must be listed in To lines except when a recipient is specifically intended to receive a blind carbon copy. Note that many voice mail systems have no facilities for storing or for reporting to the recipient the list of recipients. These systems will generally discard these headers when received. It is recommended that all messages contain the text personal name of the sender and the personal name of the recipient in comment fields if available. Cc Additional recipients fully qualified domain address. This field has no meaning beyond "To:" in a VM and is not to be generated by an conforming implementation. It is included for processing by the receiver for compatibility with general Internet mail agents which may not restrict the use of this field. If the VM supports the reporting of multiple recipients, all names in the To: and Cc: fields should be reported. Date The date, time, and time zone the message was composed by the originator or the time specified by the originator if the message is scheduled for delayed delivery. Conforming implementations must be able to convert RFC 822 date and time stamps into local time. If the VM reports message sent time, the value in this field should be used, not the time the message was received at the destination system. Example: Wed, 28 Jul 93 10:08:49 PDT Sender The actual address of the originator if the message is sent by an agent on behalf of the author indicated in the From: field.. This field is not to be generated by an conforming implementation. It is included for processing by the receiver for compatibility with general internet mail software which may generate this header. Vaudreuil Expires 10/25/94 [Page 6] Internet Draft Voice Profile April 25, 1994 The sender field often contains the name of a Internet style mailing list administrator and is the address to report errors in the event that the ESMTP MAIL FROM address is not available. While it may not be possible to save this information in some Voice Mail machines, discarding this information or the SMTP MAIL FROM address will make it difficuly to send a error message to the proper destination. Message-id A unique per-message identifier must be included by the originator for every message. Conforming systems must use an identifier constructed by concatenating with a dash the sending VMs FQDN and a 8 digit serial message number which is unique on the sending system. This identifier will be used for tracking, auditing, and returning delivery reports. Example: mycompany.com-12345678 Received Received headers are special purpose trace information added to the beginning of a RFC 822 message by message transport agents. This is the only header which is permitted to be added by a MTA. These headers are useful for debugging when using an ASCII message reader or a header parsing tool. A conforming system must add received headers when acting as a gateway. These headers must not be removed by a system when acting as a gateway. These headers may be ignored or deleted when the message is received at the final destination. MIME Version The Mime-Version: 1.0 header indicates that the message is conformant to the RFC 1341 message format specification. It must be present in any conforming message. From RFC 1341 Content-Type The content-type header declares the type of content enclosed in the message. One of the allowable contents is multipart, a mechanism for bundling several message components into a single message. The allowable contents are specified in the next section. From RFC 1341 Content-Transfer-Encoding Vaudreuil Expires 10/25/94 [Page 7] Internet Draft Voice Profile April 25, 1994 Because Internet mail was initially specified to carry only 7 bit US-ASCII text, it may be necessary to encode voice and fax data into a representation suitable for this environment. The content- transfer-encoding header describes this transformation if needed. From RFC 1341 Sensitivity This field indicates the requested privacy. If this field exists, regardless of the selected case insensitive value "Personal" or "Private". If no privacy is requested, this field is omitted. If a sensitivity header is present in the message, an conformant system is prohibited from forwarding this message. If the receiving system does not support privacy, and the sensitivity is one of "Personal" or "Private", the message must be returned to the sender with an appropriate error message indicating that privacy could not be assured and the message was not delivered. The specific privacy values do not need to be offered individually to users, but can be set on a system wide basis. Importance This field indicates the requested priority to be given by the receiving system. The case insensitive values "low", "normal" and "high" are specified. If no special importance is requested, this header may be omitted and the value assumed to be "normal". This field can be used to order messages in a recipients mailbox and is equivalent to the AMIS Priority indication. 5.3. Message Content Types MIME is a general purpose message body format that is extensible to carry a wide range of body parts. The basic protocol is described in [RFC-MIME]. MIME also provides for encoding binary data in such a manner that it can be transported over the 7 bit text oriented SMTP protocol. This transport encoding is independent of the audio encoding that is designed to generate a binary object. MIME defined two transport encoding mechanisms, one designed for text-like data, "Quoted-Printable", and one for arbitrary binary data, "Base-64". While base-64 is dramatically more efficient for audio data, both will work. A null encoding of "Binary" was specified for use in an environment where binary transport is available. Vaudreuil Expires 10/25/94 [Page 8] Internet Draft Voice Profile April 25, 1994 An implementation in conformance with this profile is required to send audio data encoded as binary where binary message transport is available. Where binary transport is not available, implementations must encode the message as Base-64. As required by MIME, and to preserve interoperability with the fullest range of possible devices, the detection of and decoding of quoted- printable must also be supported. The following content-types are profiled. Note that each of these contents can be sent individually in a message or wrapped in a multipart message to send multi-segment messages. The following content types are identified for use with this profile. Audio/Basic(RECOMMENDED) Audio/Basic was defined as 64Kbps u-law in the base MIME protocol document. Support of Audio/Basic is recommended for compatibility with current Internet workstations but not required for conformance with this profile. Message/RFC822 (REQUIRED) MIME requires support of the Message/RFC822 message encapsulation body part. This body part is used in the internet for forwarding complete messages within a multipart/mixed message. Processing of this body part entails trivial processing to unencapsulate- encapsulate the message. It is not to be sent by a system conformant to this profile but must be accepted for conformance with basic MIME. Text/Plain (REQUIRED) MIME requires support of the basic text/plain content type. This content has no applicability within the voice messaging environment and should not be sent. Behavior upon receipt of such a type is dependent upon the platform and interpretation of such a part is left as an implementation decision. Options include dropping the body part and sending a delivery report indicating the lack of support, text-to-speech, and text-to-fax support. Multipart/Mixed (REQUIRED) MIME provides the facilities for enclosing several body parts in a single message. Multipart/Mixed may be used for sending multi-segment voice messages, that is, to preserve across the network the distinction between an annotation and a forwarded message. Systems are permitted to collapse such a Vaudreuil Expires 10/25/94 [Page 9] Internet Draft Voice Profile April 25, 1994 multi-segnemt message into a single segment if they are not supported on the receiving machine. Text/Signature (RECOMMENDED) Text/Signature provides a mechanism for the sending of per-user directory information including the spoken name and the supported mailbox capabilities. When used with a caching mechanism, basic directory services with entries for commonly used entries can be maintained. This body part is to be used to support spoken name confirmation and ASCII name for dial-by-name applications. The Text/Signature can be included with a message using the multipart/mixed constructor type. From Multipart/Notification (REQUIRED) The Multipart/Delivery-Notification is used for enclosing a text/delivery-notification body part and any returned message content. This body type is a companion to and is defined with the text/delivery- report. Systems may optionally send a text description Audio/ADPCM (REQUIRED) CCITT Draft Recommendation G.721 describes the algorithm recommended for conversion of a 64 KB/s A- law or -law PCM channel to and from a 32 KB/s channel. The conversion is applied to the PCM stream using an Adaptive Differential Pulse Code Modulation (ADPCM) transcoding technique. This algorithm will be registered with the Internet Assigned Numbers Authority for MIME use under the name Audio/ADPCM. ADPCM is widely available. Support of Audio/ADPCM is required for conformance with this profile. Proprietary Voice Formats (OPTIONAL) Proprietary voice encoding formats are supported under this profile provided a unique identifier is registered with the IANA prior to use. Vaudreuil Expires 10/25/94 [Page 10] Internet Draft Voice Profile April 25, 1994 Note that use of proprietary encodings reduces interoperability in the absence of system configuration. Vaudreuil Expires 10/25/94 [Page 11] Internet Draft Voice Profile April 25, 1994 6.Message Transport Protocol (ESMTP) Messages are transported using the Internet Extended Simple Mail Transport Protocol. This protocol is used to send messages between voice mail machines. All information required for proper delivery of the message is included in the ESMTP dialog. This information, including the sender and recipient addresses is commonly referred to as the message "envelope". This information is equivalent to the message control block in many analog voice networking protocols. ESMTP is a general purpose messaging protocol, designed both to send mail and to allow terminal console messaging. SMTP was originally created for the exchange of US-ASCII 7 bit text messages. Binary and 8 bit text messages have traditionally been transported by encoding the messages into a 7 bit text-like form. RFC 1425 was recently published and formalized an extension mechanism for SMTP and subsequent RFCs have defined 8 bit text networking and extensions to permit the declaration of message size for the efficient transmission of large messages such as multi-minute voice mail. Binary transport is currently under development in the IETF. When completed, the binary extensions to ESMTP will be required for conformance with this profile. The current version of this protocol is available in the public Internet Drafts directories in the file A command streaming extension for high performance message transmission is under development in the IETF. This extension reduced the number of round trip packet exchanges and makes it possible to validate all recipient addresses in one operation. This extension is optional but recommended. This document is available in the public Internet Draft directories in the file The following ESMTP commands may be supported. 6.1. ESMTP Commands HELO (REQUIRED) Base SMTP greeting and identification of sender. This is not to be sent by conforming systems unless the more capable EHLO command is not accepted. It is included for compatibility with general SMTP implementations. MAIL FROM (REQUIRED) Originating mailbox. This address contains the mailbox to which errors should be sent. This address may not be the same as the message sender listed in the message header fields in the event Vaudreuil Expires 10/25/94 [Page 12] Internet Draft Voice Profile April 25, 1994 that the message was gatewayed or sent to a Internet style mailing list. RCPT TO (REQUIRED) Recipients Mailbox. This field contains only the addresses to which the message should be delivered for this transaction. In the event that multiple transport connections to multiple destination machines are required for the same message, this list may not match the list of recipients in the message header. DATA (REQUIRED) The command to initiate the transfer of message data. This command is required to be supported but should only be used in the event the binary mode command BDAT is not supported. TURN (RECOMMENDED) The turn command requests a change-of-roles, that is, the client which opened the connection offers to assume the role of server for any mail the remote machine may which to send. This is useful to poll for messages. (Note the security implications of using the turn command to fetch mail queued for another destination. This is possible due the lack of authentication of the sending VM by the protocol) QUIT (REQUIRED) QUIT requests that the connection be closed. If accepted, the remote machine will reset and close the connection. RSET (REQUIRED) Reset the connection to the initial state. VRFY (OPTIONAL) The VRFY command requests verification that the listed recipient is reachable by this node. While this functionality is also included in the RCPT TO command, VRFY allows the query without beginning a mail transfer transaction. This command is useful for debugging and tracing problems. (Note that the implementation may simplify the guessing of a recipients mailbox or automated sweeps Vaudreuil Expires 10/25/94 [Page 13] Internet Draft Voice Profile April 25, 1994 for valid mailbox addresses resupting in a possible reduction in privacy. Various implementation techniques may be used to reduce the threat such as limiting the number of queries per session.) EHLO (REQUIRED) EHLO is an enhanced mail greeting which enables a server to announce the support for extended messaging options. The extended messaging modes are discussed in a later section. BDAT (REQUIRED) Initiate binary data transmission The BDAT command is an alternative to the earlier DATA command. The BDAT command does not require encoding voice data into 7 bit line limited formats. All other commands must be recognized and an appropriate error code returned if not supported. 6.2. ESMTP Keywords STREAMING (Optional) The streaming keyword indicates the ability of the receiving SMTP to accept pipelined SMTP commands. (from Internet Draft SIZE (Required) The size indication provides a mechanism by which the receiving SMTP can indicate the maximum size message supported. (from RFC 1427) CHUNKING (Required) The chunking keyword indicates that the receiver will support the high performance binary transport mode. - Note that CHUNKING can be used with any message format and does not imply support for binary encoded messages. (from Internet-Draft BINARYMIME (Required) The binarymime keyword indicates that the receiver SMTP can accept binary encoded MIME messages. Note that CHUNKING mode must be supported for this option, but that CHUNKING does not mean that binary Vaudreuil Expires 10/25/94 [Page 14] Internet Draft Voice Profile April 25, 1994 messages can be supported. (from Internet-Draft 6.3. ESMTP Parameters - MAIL FROM BINARYMIME The binarymime parameter indicates that the current message is a binary encoded MIME messages. 6.4. ESMTP Parameters - RCPT TO NOTIFY The notify parameter specifies the conditions under which a delivery report should be sent. From RET The ret parameter indicates whether the content of the message should be returned. From PRIORITY This parameter indicates the requested priority to be given by the transmission network. From Vaudreuil Expires 10/25/94 [Page 15] Internet Draft Voice Profile April 25, 1994 7.Management Protocols The Internet protocols provide a mechanism for the management of voice mail machines, from the management of the physical network through the management of the message queues. SNMP should be supported on a compliant message machine. The digital interface to the VM and the TCP/IP protocols should be managed. MIB II provides basic statistics and reporting of the TCP/IP protocol performance and statistics. Media specific MIBS are available for X.25, Ethernet, FDDI, Token Ring, Frame Relay and other network technologies. This MIB provides necessary information to diagnose faulty hardware, overloaded network conditions, and excessive traffic conditions from a remote management station. Management of the machine resources and message queue monitoring based on the host MIB and the Message and Directory MIB is recommended but not required for conformance with this profile. Vaudreuil Expires 10/25/94 [Page 16] Internet Draft Voice Profile April 25, 1994 8.References [MIME]Borenstein, N., and N. Freed, "Multipurpose Internet Mail Extensions", RFC 1521, Bellcore, Innosoft, Sept 1993. [MSG] Crocker, D., "Standard for the Format of ARPA Internet Text Messages", STD 11, RFC 822, UDEL, August 1982. 3. Freed, N., "SMTP Service Extension for Command Pipelining" Internet Draft Work in Progress - 10/19/93. 4. Klensin, J., Freed, N., Rose, M., Stefferud, E., and D. Crocker, "SMTP Service Extensions" RFC 1425, United Nations University, Innosoft International, Inc., Dover Beach Consulting, Inc., Network Management Associates, Inc., The Branch Office, February 1993. 5. Klensin, J, Freed, N., Moore, K, "SMTP Service Extensions for Message Size Declaration" RFC 1427, United Nations University, Innosoft International, Inc., Inc., February 1993. February 1993 6. Klensin, J., Freed, N., Rose, M., Stefferud, E., D. Crocker, "SMTP Service Extension for 8bit-MIMEtransport" RFC 1426, United Nations University, Innosoft International, Inc., Dover Beach Consulting, Inc., Network Management Associates, Inc., The Branch Office, February 1993. 7. Mockapetris, P.,"Domain names - implementation and specification", RFC1035, Nov 1987. 8. Mockapetris, P.,"Domain names - concepts and facilities", RFC 1034, Nov 1987. 9. Postel, J., "Simple Mail Transfer Protocol", STD 10, RFC 821, USC/Information Sciences Institute, August 1982. 10. Vaudreuil, G., "Text/Signature", Internet Draft Work-in- Progress - 11/22/93. 11. Vaudreuil, G., "SMTP Service Extensions for Transmission of Large and Binary MIME Messages", Internet Draft Work-in- Progress - 11/10/93. 12. Vaudreuil, G., "An Extensible Message Format for Delivery Status Notifications", Internet Draft Work-in-Progress - 11/22/93. 9.Security Consideration Vaudreuil Expires 10/25/94 [Page 17] Internet Draft Voice Profile April 25, 1994 10. Author's Address Gregory M. Vaudreuil The Tigon Corporation 17080 Dallas Parkway Dallas, TX 75248-1905 214-733-2722 Gvaudre@cnri.reston.va.us Vaudreuil Expires 10/25/94 [Page 18] Internet Draft Voice Profile April 25, 1994 11. Appendix - Example Voice Message The following message is a full featured, all options enabled message. It is addressed to two receipients. The message includes the senders spoken name and a short speach segment. The message is marked as important and private. read receipts and positive delivery acknowledgement are requested. To: 2145551212@vm1.mycompany.com To: 2145551234@mv1.mycompany.com From: 2175552345@VM2.mycompany.com Date: Mon, 26 Aug 93 10:20:20 CST MIME-Version: 1.0 (Voice Profile Version 1) Content-type: Multipart/Mixed; Boundary = "MessageBoundary" Content-Transfer-Encoding: 7bit Return-content: Full Message-ID: VM1.mycompany.co-123456789 Sensitivity: Private-if-Possible Generate-Receipt-Notification: Generate-Delivery-Notification: Importance: High --MessageBoundary Content-type: Text/Signature Name: User, Joe, R. (Joe Random User) SpokenName: lslfdslsertiflkTfpgkTportrpkTpfgTpoiTpssdasddasdasd (This is the base-64 encoded spoken name) o45itj09fiuvdkjgWlakgQ93ijkpokfpgokQ90geQ5tkjpokfgW dlkgpokpeowrit09IpokporkgwI== Capabilities: Audio/Basic, Audio/ADPCM, Application/Signature, Image/G3Fax --MessageBoundary Content-type: Audio/ADPCM Content-Transfer-Encoding: Base-64 glslfdslsertiflkTfpgkTportrpkTpfgTpoiTpdadasssdasddasdasd (This is a sample of the base-64 message data) fgdhgdfgd jrgoij3o45itj09fiuvdkjgWlakgQ93ijkpokfpgokQ90gQ5tkjpokfgW dlkgpokpeowrit09== --MessageBoundary-- Vaudreuil Expires 10/25/94 [Page 19] Internet Draft Voice Profile April 25, 1994 12. Appendix - Example ESMTP Transaction The following ESMTP transaction represents the successful sending of a simple message to a system which does not support extended transport modes. Non-ESMTP protocol events are noted in Italics. ESMTP commands and significant significant replies are in Bold. Except for the replies to the EHLO command, the text following the reply code is optional. Sender Receipient Wait for TCP Connection Initiate TCP Connection to Port 25 Accept TCP Connection 220 ready EHLO vm1.mycompany.com 250-hello 250 SIZE 100000 MAIL FROM: <2145551212@vm1.some.com> 250 Address OK RCPT TO: <2145551234@vm2.some.com> 250 Address OK DATA 354 Send Message To: 2135551234@vm2.some.com From: 2145551212@vm1.some.com MIME-Version: 1.0 Content-Type: Audio/ADPCM Content-Transfer-Encoding: Base64 JFsdfjlkdjflkjsd lfflskjslkfjslfkjlsk ksdjlksjlfksjflkjsljsldkfjlskfjlskjff lkjsdlkfjslkdjflskksjfsdfsdf= . 250 OK QUIT 250 Goodby Receiver closes TCP connection