|
|
Libre Texting: An Industry Initiative
Neda Communications, Inc.
Document # PLPC-110015
June 15, 2009
Available on-line at:
http://www.neda.com/PLPC/110015
This article describes Libre Texting, a new incarnation of the Mobile Email/Wireless Texting (henceforth just “Texting”) medium, based on the principles and ideology of Free Software. Today the Texting industry is dominated by the proprietary, walled-garden model. The Libre Texting model provides equivalent functionality to existing proprietary Texting solutions such as BlackBerry, but (a) based entirely on patent-free protocols and free software, (b) using any mobile Internet device, and (c) wherever any type of wireless Internet connectivity is available.
The Libre Texting model we describe comprises five major elements: (1) the inherent propagative power of the Free Software and end-to-end models, (2) an Overlay Network architecture, (3) a new set of messaging protocols, (4) a novel software architecture for Message Transfer Agent integration, and (5) a new software architecture for multiform device integration, based on Device-Resident End-MTA middleware.
The key to technical implementation of Texting is the right set of protocols. Existing email protocols are inadequate in several respects—they lack push-mode delivery, and they also lack the bandwidth and power efficiency necessary for wireless applications. The proposed new protocol profile addresses and corrects these shortcomings.
Libre Texting is highly synergistic with current industry dynamics, including: a burgeoning recognition of the power of Free Software, ready availability of Linux-based mobile devices, and widespread Wi-Fi availability.
Libre Texting is a transformative technology. It allows the current walled-garden hegemony to be broken, creating a new point of convergence as the standard. This has major engineering, business and societal consequences, with tangible benefits to the end user. For example, greatly expanded range of choice—the user can now make independent selection of each component of her Texting setup, including the user interface, the Mail User Agent, the device, and other desired components (forwarders, synchronizers, filters etc.). The Libre Texting technology unbundles the Texting application, opening every point of the Texting technology chain to competition and best-in-class component selection. Furthermore, the Libre model opens the Texting industry to the powerful free software generative dynamics.
In terms of business, the Libre Texting initiative represents a radical shift of the Texting industry to the non-proprietary, for-profit quadrant, causing a major industry reconfiguration, with significant winners and losers. The losers are the existing vested proprietary interests, whose economic hegemony vanishes. But the winners are the many more companies who can now enter the Texting market—and the end user who benefits from the resulting competition.
Regarding broader societal consequences, the Libre model provides assurances of transparency, privacy and freedom of speech—assurances that are absent under the proprietary model.
This document is one of a series of documents that together describe every aspect of Libre Texting, Libre Services and By* concepts. These are:
It is recommended that these documents be read together.
In this article we describe a new incarnation of the Mobile Email/Wireless Texting medium (henceforth just “Texting”), based on the ideological principles of Free Software. We refer to this new incarnation as the Libre Texting model. Texting is already well established as a communications medium. But today the Texting industry exists in the form of a proprietary, walled-garden model, controlled by a small number of powerful proprietary commercial interests. The Libre Texting model provides equivalent functionality to existing proprietary Texting solutions such as BlackBerry, but:
The Libre Texting initiative has two distinct parts: what we call the “model” part, and the technology part.
The model part refers to the technocratic context within which the Texting functionality exists and is delivered. The proposed model is completely non-proprietary, or Libre. This means that the Texting service is based exclusively on patent-free protocols, implemented exclusively in free software, and conforms fully to the Internet end-to-end principle.
The upshot of all this is that Libre Texting does not carry any restrictive limitations on its dissemination, implementation, or usage by anyone.
The technology part consists of the technological components required for practical, large-scale implementation of Libre Texting. The critical enabling technology consists of the following four components, acting together in close integration:
Note that the Libre Texting initiative is not primarily about new or enhanced messaging functionality. In terms of capability, Libre Texting provides essentially equivalent functionality to existing Mobile Messaging/Texting solutions such as the proprietary BlackBerry system. Rather, it is about a radically new model for ownership, development and delivery of this functionality.
This article describes the Libre Texting model, and the technology required for practical implementation of this model, on a multiplicity of devices, and at very large (planet-wide) scale.
The mobile messaging industry of today is a closed, proprietary construct. Existing wireless texting/messaging implementations (telephony SMS, and mobile email solutions such as BlackBerry) are walled-garden implementations, closely protected by patents, copyright and trade secrecy. The wireless phone companies and/or their business partners own and control every component of the messaging service, including the device, the protocols, the software and the network.
In addition to their proprietary nature, existing solutions violate the Internet end-to-end principle by implementing centrally controlled, service-provider store-and-forward components as a function “within” the network. This is in contrast to the Internet email architecture, which is end-to-end.
Until quite recently, implementation of a Texting solution outside these walled-garden environments has been blocked by absence of the necessary non-proprietary components, such as open devices and public wireless spectrum. But now a completely non-proprietary, end-to-end Libre Texting solution is technically possible. This is enabled by a number of industry developments:
Thus all the necessary industry assets are now in place to implement a completely Libre Texting service. Every component of the service can be implemented in an open form, without any closed or proprietary or dependencies. This includes the device, the protocols, the software, and access to the wireless network.
The Libre Texting model is also in line with major cultural and strategic dynamics now prevailing throughout the industry.
The existing Texting/Mobile-Email industry is dysfunctional and unstable in a number of respects. First, the industry is severely fragmented. In 2010 there are five major mobile messaging players: (1) BlackBerry, (2) AT&T + Apple iPhone, (3) Sprint + Palm Pre, (4) T-Mobile + Google Android, and (5) Microsoft PocketPC. These all provide essentially the same functionality. Yet these are isolated islands of functionality, based on different devices, different protocols, and different Mail User Agents, none of which are cross-compatible. A systems integrator or user cannot mix and match among these components. And as additional industry players attempt to muscle their way into the enormous Texting market, there is every indication that this fragmentation will increase, at least in the short term.
But in the long term, this situation is untenable. As a global communications medium, there are strong forces of convergence towards a single dominant solution. Sooner or later the industry must and will coalesce around a unified Texting solution, providing across-the-board, industry-wide standardization.
In addition, there are strong strategic forces pressing for change within the industry. Today the industry is a proprietary hegemony, from which small business players are excluded. Also excluded are some very large players, exceedingly covetous of the lucrative Texting market. Thus there is great pressure to break the walled-garden regime, by powerful forces outside the walled garden.
Given all this, a major industry shift of some sort is inevitable. Whether acting individually or in concert, there is strong motivation among the industry players to preemptively fabricate, and lay claim to, the eventual point of convergence. The preemptive fabrications may take many forms, but are likely to be quasi-Libre constructs, superficially resembling the true Libre solution we propose.
The Libre Texting model is ideally constituted to emerge as the decisive point of stability and convergence within this environment. In contrast to the proprietary incumbents, and any quasi-Libre pretender, Libre Texting is not constrained by any form of proprietary ownership mechanism such as patents or restrictive copyright. This is the fundamental generative power of the free/Libre model. It is this power that can cause Libre Texting to displace the existing proprietary regime, in the face of ferocious attempts by very powerful vested interests to defeat it.
Furthermore, there is a growing cultural awareness of the tremendous power of free and open source software (FOSS), and a dawning recognition that this is slowly engulfing the proprietary software industry. Thus there is a cultural tropism towards acceptance of the Libre model in both ideological and practical terms.
Our goal is to establish Libre Texting as the point of convergence and the common standard for operation of all devices, and all message transfer services, worldwide. We believe Libre Texting is the right solution at the right time. The inherent generative power of the Libre model, together with the current industry instabilities, together with the enabling technological components we describe, coupled with the right sort of engineering and business execution—all this can destroy the existing proprietary regime completely, outstrip any quasi-Libre hijack attempt, and establish Libre Texting as the new industry standard.
It is also worth noting that the shift to Libre Texting is evolutionary in nature. While the model and its effects are revolutionary, deployment and adoption of Libre Texting requires no abrupt technological discontinuity—its deployment and growth can proceed gradually and organically. Libre Texting can initially be introduced into the existing proprietary environment as quietly as inserting a thermometer.
A consistent terminology for wireless texting/messaging has not yet been established, and terms such as “texting,” “wireless messaging,” and “mobile email” are often used interchangeably, and with different meanings. “Texting” is often used in the context of telephony SMS, and “messaging” is often used in the context of mobile email, but this usage is by no means universal. The best we can do is define our own terms clearly.
Throughout this document we are talking about an email-type service, with a richer functionality than today’s telephony SMS. Specifically, we use the term Texting to mean a mobile messaging service that:
In terms of model, we now formally define Libre Texting as a Texting service that:
We also define a Libre Texting Device as a device that:
Note that there is no implication that the device is necessarily a traditional data-enabled mobile phone. To the contrary, our baseline assumption throughout this document is that the device takes the form of a typical Wi-Fi-based Mobile Internet Device (MID).
Note also that Wi-Fi specifically is not a necessary requirement. Wi-Fi capability is now near-universal in mobile devices, so that this is in fact the most common form of last-leg device connectivity. But any form of wireless Internet connectivity will suffice.
In 2010 a large number of Libre Texting Devices are available in the marketplace, including Nokia n800/n810, Nokia n900, unlocked Android, unlocked iPhone, PocketPC, and others.
Of course any netbook is also entirely capable of supporting Libre Texting, though it lacks the unconscious-carry form factor. But our primary focus is on the more unconsciously portable devices as defined above.
We assume the following initial conditions as a starting point: (1) the user already has or will independently acquire a Libre Texting Device as defined above, and (2) the user has final-leg Wi-Fi (or other wireless) connectivity to the Internet.
Setting up Libre Texting service starts with provisioning the user with the necessary accounts and access credentials. She starts by accessing the generic Libre Texting website (from any point of Internet access), and creating a new account for herself. At the time of account creation, the following items are created for her:
Next, we set up her mobile device with the necessary software, and configure the device with her account credentials. Now specifically using the mobile device, she manually logs in to her Libre Texting website account and invokes the device setup procedure. The setup queries her for the device make and model number, then following proper confirmation the setup automatically downloads the free Libre Texting software to her device, and configures it with her credentials for automatic access to the Overlay Network, and automatic access to her Libre Texting account.
She is now good to go. She now has complete Libre Texting capability from her device, including immediate push-mode delivery.
Figure 1 shows how Libre Texting delivers functionality to the user. The EMSD-specific components (EMSD User Agent and EMSD Server) are shown in green in the figure. The Overlay Network at the bottom of the stack (shown in yellow) is used whenever EMSD connectivity is needed.
Under one scenario, Libre Texting service can be provided by an independent email service provider (the box labeled “EMSD Enabled Service Provider” in the center of the figure). Under Libre Texting this role can be played by any Message Center operator—for example, by any one of the large number of existing ISP companies. All that is required for an ISP or other Message Center operator to become a provider of EMSD-based mobile messaging services, is for them to install the necessary EMSD Message Center software.
Anyone with access to the Internet can now exchange emails with the mobile user. Emails addressed to the mobile account are fielded by the email service provider from the generic Internet using standard Internet protocols, then delivered to the mobile device using the EMSD protocols.
The Message Transfer System may include a number of EMSD Server Agents (EMSD-SAs). Each EMSD-SA may have any number of EMSD User Agents (EMSD-UAs) with which it communicates.
To send a message, the user composes the message then submits it to the EMSD service provider via the EMSD protocols. The service provider then sends the message to its destination using standard Internet email protocols.
Users typically wish their mobile messaging capability to function as a wireless extension of an existing land-based email account. For example, the user may wish the mobile device to act as an extension of a home or office desktop mail application, as shown at the top of Figure 1. This functionality is provided by installing the appropriate mail forwarding software on the desktop system. This software integrates with the desktop mail application, and allows messages to be selectively forwarded to the mobile device on the basis of user-defined email filters. Properly qualified emails are forwarded to the EMSD service provider using standard email protocols, then delivered to the mobile device using the EMSD protocols.
Note that the user does not install EMSD software on his desktop; rather he installs forwarder software—the desktop knows nothing of EMSD.
When the user submits a message from the mobile device, the EMSD service provider sends the message to its destination as usual, and in addition it can send a notification to the desktop mail application, to maintain mailbox synchronization between the handheld device and the desktop system.
Under a different scenario, Libre Texting capability can be part of a corporate email system, as shown at the bottom of the figure (the box labeled “Corporate Email System”). This functionality is provided by installing the appropriate EMSD software in the corporate Message Center.
By definition, the Libre Texting Device has some form of wireless Internet connectivity. The most common situation is where the device has Wi-Fi connectivity behind Network Address Translation (NAT), with a leased dynamic private IP address.
Regardless of the wireless modality, it must be extended to achieve NAT traversal, for mobility and presence detection (needed for push-mode operation), and for security enhancement. Our reference implementation uses an Overlay Network architecture to accomplish this. The Overlay Network resides on top of the existing network structure, and provides the following requirements:
The device first establishes initial Internet connectivity, typically behind a NAT. Based on that initial connectivity the device then signs on to the Overlay Network based on its unique static IP address, and is now end-to-end, two-way connected. Thus the device is always reachable by the server. Reachability while mobile is in effect accomplished by the static IP address.
The Overlay Network architecture also gives us immediate presence detection, allowing prompt message push delivery. In other words, the moment the device is reachable, the MTA becomes aware of the device. By means of the Overlay Network we become in effect a network operator, without owning a physical network.
We are using the term Overlay Network in a broad generic sense. The actual overlay capability can be provided by any of the following technologies:
All these are viable candidates, and possible future evolutionary directions for Libre Texting. A key consideration for selecting one or more of these for support is ready availability of free software for implementation of these technologies on Libre Texting Devices.
The starting point choice for our reference implementation is OpenVPN. OpenVPN is a widely used, free and open source virtual private network (VPN) program for server-to-multiclient encrypted tunnels between MTAs and Mobile Texting Devices. This is entirely adequate to our purposes, and has widely available free software implementations.
Note that we exclude public and private mobile IPv4 from the list of candidate technologies. We exclude public IPv4 because of exhaustion of the address space. We exclude private mobile IPv4 because it is essentially equivalent to Virtual Private Network, and because software for Mobile-IPv4 is not widely available for mobile device platforms.
Figure 2 shows three major scenarios for connection between the device and the open Internet, and extension of this connectivity by the Overlay Network. The right of the figure shows the simplest situation, where the user has direct Wi-Fi Internet connectivity.
The center of the figure shows a situation where a wide-area network (either broadband or narrowband) is used for second-to-last leg connectivity. For example via public spectrum MURS, or using a mobile wide-area Wi-Fi hotspot appliance such as MiFi for use with the cellular network.
The left of the figure shows a situation where Internet connectivity is via multiple concatenated Wi-Fi links. This often happens when a user with Wi-Fi access chooses to share that access by providing an “easement” to others who may have been previously restricted.
The key component of our reference implementation is a set of mobile messaging protocols called the EMSD protocols. The EMSD protocols fully satisfy the necessary technical requirements for mobile messaging. They provide the efficiency required for wireless applications, and support push-mode message delivery, an essential requirement for the expected immediacy of Texting.
The EMSD protocol, titled:
Neda’s Efficient Mail Submission and Delivery (EMSD) Protocol Specification Version 1.3
was published as Internet RFC-2524 [11] in 1999.
The EMSD protocol provides reliable connectionless mail submission and delivery services on top of ESRO. The ESRO protocol, titled:
AT&T/Neda’s Efficient Short Remote Operations (ESRO) Protocol Specification Version 1.2
was published as RFC-2188 [12] in 1997.
Existing Internet email protocols are not suitable for Texting/Mobile Email, because they fall short in two major respects. First, they lack the necessary efficiency characteristics. Wide-area narrowband wireless networks are severely constrained by bandwidth limitations, and mobile devices are constrained by limitations such as display size, battery capacity, and memory size. These constraints place an extremely high premium on the efficiency of data transfer. Existing Internet protocols such as SMTP, IMAP and POP do not provide the required efficiency.
Second, existing Internet email protocols do not properly support the push mode of delivery. For more detailed discussion of the shortcomings of existing protocols, see the article EMSD: The LEAP E-Mail Component [2].
EMSD narrowly focuses on submission and delivery of short mail messages with a clear emphasis on efficiency. It is designed specifically with wireless network usage in mind. EMSD is designed to be a natural enhancement to the mainstream Internet mail protocols, when efficiency in mail submission and mail delivery are important.
SMTP is the main mail transport mechanism used throughout the Internet. However, SMTP is highly inefficient for the transfer of short messages. SMTP is inefficient both in terms of the number of transmissions, and in terms of the number of bytes transmitted. Even when fully optimized with PIPELINING [case?], SMTP remains significantly inefficient.
Table 1 shows the number of N-PDUs exchanged for the transfer of a short Internet email when using SMTP, SMTP with PIPELINING, QMTP, and EMSD. The names used for identifying the PDUs are informal names.
|
|
The submission of a short message using SMTP requires 15 transmissions. The submission of a short message with SMTP and PIPELINING requires 9 transmissions. The submission of a short message with EMSD (EMSD-P and ESRO) typically requires only 3 transmissions.
The key design requirement of EMSD is efficiency. Because of the threefold (at least) gain in efficiency, this justifies the deviation from the SMTP model.
For mail submission and delivery of short messages EMSD is up to 5 times more efficient than SMTP, both in terms of the number of packets transmitted, and in terms of number of bytes transmitted. Even with PIPELINING and other possible optimizations of SMTP, EMSD is still up to 3 times more efficient than SMTP, both in terms of the number of packets transmitted, and in terms of number of bytes transmitted.
Various efficiency studies comparing EMSD with SMTP, POP and IMAP are available. A detailed theoretical and empirical comparison of SMTP and EMSD is available in Efficiency of EMSD [1].
In order to provide the same level of reliability that the existing email protocols provide for short messages, it is clear that a reliable underlying service is needed. UDP by itself is clearly not adequate.
Use of TCP however, involves three phases:
The reliable transfer of a short message using TCP involves a minimum of five transmissions, as is the case with QMTP.
The ESRO protocol provides reliable connectionless remote operation services on top of UDP with minimum overhead. ESRO supports segmentation and reassembly, concatenation and separation.
The reliable transfer of a short message using ESRO involves 3 transmissions, as is the case with EMSD-P.
In order to minimize the number of bytes transfered, efficient encoding mechanisms are needed. By selecting ASN.1 as the notation used for expressing the EMSD information objects, EMSD has the flexibility of using the most efficient encoding rules, such as Packed Encoding Rules (PER).
EMSD is designed to be a companion to existing Internet mail protocols. It is designed to fit within the many protocols already in use for messaging.
The various Internet mail protocols provide different sets of capabilities for mail processing.
Table 2 summarizes the capabilities of SMTP, IMAP, POP and EMSD in different areas of functionality. The number of X’s in each cell indicate how well the function is supported by these protocols.
|
|
The table clearly shows that combinations of these protocols can be used to complement one other in providing rich functionality to the user.
For example, a user interested in highly mobile messaging functionality can use EMSD for the submission and delivery of time-critical and important messages, and use IMAP for comprehensive access to his/her mailbox.
From the very beginning, the Internet email architecture was not monolithic. Rather, it takes the form of a set of specialized protocols working together.
An important consideration is that Libre Texting must fit naturally into the existing structure of the Internet email service. Libre Texting may be disruptive in terms of model, but it must not be disruptive in terms of technological implementation. To facilitate ready industry adoption, the Libre Texting protocols must fit in a straightforward way into existing Message Transfer Agents.
The great majority of Internet email traffic is currently handled by the following MTAs: qmail, Sendmail, Microsoft Exchange, Postfix, Exim.
Figure 3 shows the software architecture used for integration of EMSD-SA into the qmail Mail Transfer Agent. This particular architecture is specific to Linux and qmail, but we expect that integration with the other major MTAs can be accomplished based on a similar scheme.
The configuration in Figure 3 consists of the usual qmail architecture (shown in blue), with emsd-sa-submitd (shown at the top in green) added as a module to process incoming EMSD traffic. The architecture of emsd-sa-submitd is similar to that of mailfront, which is a modern modular replacement for qmail-smtpd. This architecture permits sharing of the Credential Validation Module (cvm), and the Credentials, between emsd-sa-submitd and mailfront.
Based on the presence detection information acquired from the Overlay Network, EMSD deliveries are initiated immediately the device becomes reachable.
[MB to fix up] The novel and experimental (unproven) part of this proposed architecture is the linkage between the Presence Detection module (shown in orange) and qmail-queue. Apart from its main input, output and timers, qmail-queue is not event driven. An important technological objective is to investigate the feasibility of reusing or modifying the queuing and spooling system of qmail, in conjunction with lower-layer presence detection for immediate EMSD delivery.
Since all software shown in Figure 3 is free/Libre Software, EMSD-enabled MTAs can be deployed by anyone wishing to implement Libre Texting.
Towards our goal of widespread industry adoption, the Libre Texting protocols must fit in a straightforward way into many end user devices, running a variety of Mail User Agents (MUAs). To facilitate this there must be minimal disruption of the existing MUA architecture.
We use an architecture based on the concept of a Device-Resident End-MTA middleware module, acting as intermediary between the protocol software and the MUA.
Figure 4 shows the software architecture for integration of EMSD-UA with qmail to create a Device-Resident End-MTA. On its external interface (shown in grey and yellow at the bottom of the figure), the Device-Resident End-MTA interacts with the Internet at large using EMSD, SMTP, and IMAP. On its internal interface (local loop-back interface; address 127.0.0.1) the Device-Resident End-MTA interacts with the MUA based on SMTP and IMAP. Thus the MUA need have no awareness of EMSD at all. This architecture is quite general and can be used on almost all platforms. In this model, the MUA is always configured for the 127.0.0.1 interface for the SMTP gateway, and the IMAP server. The Device-Resident End-MTA is then configured with the real external server information.
offlineimap is used to optionally synchronize the device’s mailstore/Maildir (shown in grey) so that the user’s inbox is locally available, even when there is no network connectivity.
Though this architecture is based on qmail, the resulting Device-Resident End-MTA package is quite general, and can be installed in all Linux PDA platforms, and very likely other platforms too.
Note that because all software shown in Figure 4 is free/Libre software, the Device-Resident End-MTA can be made available on any Linux-based device without any restrictions.
As an open solution, Libre Texting unbundles the Texting technology chain. Figure 5 shows the major technology components, and some of the choices presently available. In general, these components are now decoupled, allowing independent competition and selection for each component.
Some technical dependencies exist between Wi-Fi Routers and Networks (e.g. Novatel MiFi, tied to the 3G cellular networks), but as time goes on we can expect these components to become increasingly decoupled also, as Routers become general-purpose multi-network wireless companion devices.
Libre Texting provides major benefits for the industry and the end user.
As an open solution, Libre Texting has the effect of unbundling the Texting application, exposing every point of the Texting technology chain to free market entry and competition. Furthermore, the Libre model opens the Texting industry to the powerful generative dynamics of the free software development model.
This results in greatly increased business opportunities, technical innovation, and unrestricted industry growth. These dynamics promote constantly increasing richness of features and functionality, in ways we can imagine today, and ways we cannot. One entire branch of technical innovation we can readily imagine consists of a new class of applications residing on top of Libre Texting. For example: caller ID information can be pushed directly to the mobile user, for a telephone call received on the land line.
All this will directly benefit the end user, who will have greatly expanded range of choice, increased features and functionality, mix-and-match component selection—and all this, almost certainly, at more competitive prices.
The Libre model also provides assurances of a number of critical freedoms and civil liberties, including privacy and freedom of speech. These liberties are certainly not assured under the proprietary model.
Here we describe some previous and on-going work related to the present initiative.
In 1995 AT&T Wireless Services began development of a wireless messaging system called personal Air Communications Technology (pACT). The spectrum for pACT was Narrowband PCS, and the lower layers of pACT were based on CDPD technology [3], the first nationwide native mobile IP network. The pACT messaging protocols were designed for efficient IP-based mobile messaging/texting. In effect, pACT was functionally equivalent to the popular mobile email solutions of today such as BlackBerry.
Neda Communications played a major role in the development of the pACT system. In particular, Neda engineering staff were the primary architects of the mobile messaging component of pACT. Previous to this these same engineering staff had played an active role in the development of CDPD.
AT&T spent about $500M on the development of pACT, including $160M for the purchase of nationwide Narrowband PCS licenses. But then in March 1997 AT&T abandoned the pACT wireless messaging project entirely, and elected not to maintain or further pursue any of the pACT technology.
But recognizing the significance and importance of this, Neda completed development of the protocols independent of AT&T, and published them as RFC-2188 (1998) [12], and RFC-2524 (1999). The primary author of these RFCs has made patent-free declarations for both protocols through the Free Protocols Foundation.
Since 2003 the Lemonade working group at the IETF has been attempting to provide a set of enhancements and profiles of Internet email submission, transport, and retrieval protocols to facilitate operation on platforms with constrained resources, or via communications links with high latency or limited bandwidth. A primary goal of this work is to ensure that those profiles and enhancements continue to interoperate with the existing Internet email protocols in use on the Internet, so that these environments and more traditional Internet users have access to a seamless service.
Various other groups are also active in this area, including:
All these groups are dominated by existing vested interests and are therefore unlikely to be ready or willing to accept the Libre model in full.
Libre Texting as presented in this proposal is not in conflict with Lemonade [16] [15] [13], but with respect to initial submission and final delivery of messages takes a more pragmatic and efficient approach.
The EMSD protocols address the key missing features (push-mode delivery and efficiency) needed for mobile email, while Lemonade attempts to address various peripheral features.
Push-IMAP (also known as P-IMAP, or Push extensions for Internet Message Access Protocol) is based on IMAPv4 Rev1 (RFC 3501) [14], but contains additional enhancements for optimization in a mobile setting. Push-IMAP was not included in the Lemonade Profile (RFC 4550) [16], and is only available as an internet-draft.
Though they are both based on IMAP, neither Yahoo Mail nor MobileMe for iPhone uses a standard form of Push-IMAP. Yahoo Mail uses a proprietary extension to the IMAP protocol, and Apple’s MobileMe uses a server within Apple that maintains a persistent IP connection to each iPhone, which allows push email.
We believe that our use of EMSD for Libre Texting has a number of advantages over the Push-IMAP approach. These include: superior efficiency [1], NAT traversal by means of an Overlay Network rather than maintaining a persistent TCP connection, and native push-mode delivery instead of extending IMAP in a non-standard way.
The Libre Texting model has immense business consequences.
Libre Texting represents a radical shift of the Texting industry to the non-proprietary, for-profit quadrant. This can be expected to cause a major industry reconfiguration, with significant winners and losers. The losers are the existing vested proprietary interests, whose economic hegemony vanishes. But the winners are the many more companies who can now enter the Texting market—and the end-user who benefits from the resulting competition.
ByStar Libre Texting Business Plan [4]. Describes the business dimension, an essential component for real-world
adoption of the Libre Texting model. Describes revenue models, and makes the case for deployment of Libre
Texting services in a commercial context.
http://www.neda.com/PLPC/110019
Every aspect of this initiative is Libre—all assets are web published and available as a communal public resource. We invite you to evaluate our analysis and documents, and participate in this new texting model in your own context.
Finally, if you think the Libre Texting initiative has merit, we ask you to help spread the word. Please feel free to distribute this article to others who may be interested, either in toto, or in the form of the following link to its website location: http://www.neda.com/PLPC/110015
[1] ” Mohsen BANAN ”. ” emsd efficiency ”. Permanent Libre Published Content ”100003”, Libre Content, ”October” 1996. http://www.freeprotocols.org/PLPC/100003.
[2] ” Mohsen BANAN ”. ” emsd: The leap e-mail component ”. Permanent Libre Published Content ”100026”, Libre Content, ”August” 2000. http://www.freeprotocols.org/PLPC/100026.
[3] ” Mohsen BANAN ”. ” internetwork mobility – the cdpd approach ”. Permanent Libre Published Content ”120021”, Libre Content, ”December” 2007. http://mohsen.banan.1.byname.net/PLPC/120021.
[4] ” Mohsen BANAN ”. ” bystar libre texting business plan ”. Permanent Libre Published Content ”110019”, Libre Content, ”June” 2009. http://www.neda.com/PLPC/110019.
[5] ” Mohsen BANAN ”. ” bystar libre texting proposal for isps/asps and handset manufacturers ”. Permanent Libre Published Content ”110017”, Libre Content, ”June” 2009. http://www.neda.com/PLPC/110017.
[6] ” Mohsen BANAN ”. ” libre texting: A collaborative initiative and a reference implementation ”. Permanent Libre Published Content ”110015”, Libre Content, ”June” 2009. http://www.neda.com/PLPC/110015.
[7] Andrew Hammoude ” ” Mohsen BANAN. ” the free protocols foundation policies and procedures ”. Permanent Libre Published Content ”100201”, Libre Content, ”March” 2000. http://www.freeprotocols.org/PLPC/100201.
[8] Andrew Hammoude ” ” Mohsen BANAN. ” libre services a non-proprietary model for delivery of internet services ”. Permanent Libre Published Content ”100101”, Libre Content, ”March” 2006. http://www.freeprotocols.org/PLPC/100101.
[9] Andrew Hammoude ” ” Mohsen BANAN. ” the by* concept: A unified model for internet services ”. Permanent Libre Published Content ”110001”, Libre Content, ”January” 2007. http://www.neda.com/PLPC/110001.
[10] Andrew Hammoude ” ” Neda Communications, Inc. ” the by* family of libre services: The future of the internet services industry an open business plan ”. Permanent Libre Published Content ”110002”, Libre Content, ”March” 2009. http://www.neda.com/StrategicVision/BusinessPlan.
[11] M. Banan. Neda’s Efficient Mail Submission and Delivery (EMSD) Protocol Specification Version 1.3. RFC 2524 (Informational), February 1999.
[12] M. Banan, M. Taylor, and J. Cheng. AT&T/Neda’s Efficient Short Remote Operations (ESRO) Protocol Specification Version 1.2. RFC 2188 (Informational), September 1997.
[13] E. Burger and G. Parsons. LEMONADE Architecture - Supporting Open Mobile Alliance (OMA) Mobile Email (MEM) Using Internet Mail. RFC 5442 (Informational), March 2009.
[14] M. Crispin. INTERNET MESSAGE ACCESS PROTOCOL - VERSION 4rev1. RFC 3501 (Proposed Standard), March 2003. Updated by RFCs 4466, 4469, 4551, 5032, 5182.
[15] R. Gellens. Deployment Considerations for Lemonade-Compliant Mobile Email. RFC 5383 (Best Current Practice), October 2008.
[16] S. Maes and A. Melnikov. Internet Email to Support Diverse Service Environments (Lemonade) Profile. RFC 4550 (Proposed Standard), June 2006.
