1. Field of the Invention
This invention relates to data communications between digital systems through wireless communications networks. It is an innovative and non-obvious melding of computer technology, RF technology, and data communications technology to solve many crucial problems of wireless information communications. This invention provides a new communications paradigm (called “POST”) to provide ubiquitous information via seamless, secure data transmission through various types of intermittent and sporadic wireless communications channels.
2. Description of Related Art
a. Introduction
The promise of wireless data communication is that it will free the users from being tied down to the office, or having to return as often to their base of operations. Wireless data communications can provide this freedom to that large segment of the workforce that is most productive when the mobile worker remains “in the field.”
In practice, however, given the current state of wireless data communications technology, the data communications capabilities of the office worker (and corresponding efficiency and productivity) vastly outweigh that of the mobile worker. The current limitations with today's state-of-the-art systems, which are addressed with the invention described herein, are many:
b. Current Status of Wireless Data Connections
One commonly hears wireless communication protocols described in terms of the initiation of communication, such as: “Push,” “Pull,” and “Dock.”
“Pull” refers to the inquiry/response method that is common for use with devices such as wireless Palm Pilots, wireless-equipped PocketPCs, Nokia Communicators, and Handspring TREO. The interchange is initiated by the end-user. First of all, one must be connected on an RF basis. Then, a request is entered into the device and transmitted. Because of slow transmission speeds, there is some wait period for transmission and reply, plus processing time on the fixed end. The user must stay connected during this period. Replies are typically short, consistent with the storage memory and display screen limitations on these devices.
Typical problems with Pull-initiated communications are as follows: (1) limited memory and slow transmission speeds focus these devices on simple answers to simple questions; (2) the answers that are received are held in memory without any attempt at security; (3) if used for e-mail, there is no common ‘sent mail’ record (that is, common among a person's other e-mail capable devices); (4) RF reliability and availability; (5) old downloaded information may be used if the owner forgets to request the most resent version of a document; and (6) there is no guaranteed delivery, because the system counts on the user requesting a repeat transmission if the information is garbled.
“Push” refers to one-way communications initiated by the fixed end equipment. Commonly used devices include the RIM Blackberry and the Motorola PageWriter, and are principally used for e-mail. The advantage over Pull devices is that the user does not have to find a location with suitable RF coverage; the system keeps trying to contact his device, and when it does it ‘pushes’ information out to the device. A Push system works best when the target device is always turned on, which may present battery life challenges.
The major challenge for Push technologies is that the device may not be appropriate for the information being sent to it. The sender does not know whether the attachment will be received by a desk computer equipped with MS-Office software, or a small device in the field with text-only capabilities. Transmission time could be one second, or 1000 seconds. The conventional work-around has been to send only the message headers to the Push device, and then let the user determine which messages to download. Clearly, this increases latency and user involvement.
Many Push devices can also act as Pull devices. As noted above, typical problems include: (1) limited memory and slow transmission speeds focus these devices on simple answers to simple questions; (2) the answers that are received are held in memory without any attempt at security; (3) if used for e-mail, there is no common ‘sent mail’ record; and (4) RF reliability and availability.
The third category in communication initiation is called “Dock.” Under this ad-hoc sync scheme, the user connects to their enterprise by visiting a “hot-spot” such as Starbucks, hotel, airport lounge, or other access point location. (This is similar to using a payphone.) Just as if they had gone to their office and docked their computer, the user now has the ability to connect at relatively high speed (<1500 kbps) and synchronize files or access information. Services offering this ability include BOINGO, Cometa Networks, and T-Mobile. Both Sprint PCS and AT&T Wireless offer this capability over WWAN, at a much slower speed (less than dial-up).
Typical disadvantages with this approach include: (1) the user must stay in the location until done; (2) if using web-based file storage, one must know in advance what one wants to download and arrange for it to be available; (3) there is no single store of information, i.e., different files and versions of files will exist on a user's PocketPC, home computer, office computer, and laptop; and (4) many files are shared with others, so that a file change may cause irreconcilable versions when one finally “Docks.”
The speed of current data communications (to an individual device) through wireless communications networks vary widely. Wireless Local Area Networks (WLANs), as mentioned above, provide fairly high-speed communications with brief latencies (although speed is usually limited by the supporting infrastructure to less than 1500 kilobits per second—and further limited if there is more than one active user). Users generally connect to WLANs while inside, or within approximately 100 feet of, a building equipped with a WLAN. However, WLANs are not suitable for users who spend much of their time in vehicles, traveling from one point to another, because WLANs are short-distance devices (by FCC power restrictions) and are typically used as a data communications infrastructure inside of buildings.
Wireless data-only and cellular networks, collectively referred to as Wireless Wide Area Networks (WWANs), use the wireless telephone infrastructure, or a dedicated infrastructure, to connect with users and transmit their data. Data transmission speeds are significantly slower than WLANs; however, these are the only technologies that are able to maintain contact with users in typical travels around the state. Wireless data-only networks are similar to cellular, but current deployments have been limited to metropolitan areas. Speeds of up to 70 kbps are now available, although less than 40 kbps (dial-up speed) is more commonly achieved.
C. System Response Latency with Current Technology
WLANs generally do not have latency problems. In general, their response times are less than 2 seconds.
The new Wireless (Telephone) Wide Area Networks (WWANs), using standards such as CDMA-1XRT and GSM/GPRS, provide users with much slower connection speeds (approximating dial-up performance) than are found in either hardwired or wireless local area networks. Thus, latency from queuing and slow transmission speeds will often be a significant problem when using these networks. For example, RIM Corporation's description of its Blackberry 2-way e-mail system states that a request to a user's mail server and the response from that mail server takes up to 30 seconds to complete through a WWAN (≅10 kbps). In comparison, it generally takes less than ½ second to achieve the same response on an office LAN (>10,000 kbps).
d. Dead Areas with Current Technology
Wireless telephone communications have numerous areas where a wireless connection cannot be obtained. In the current communications model, when a wireless connection path is not available to the wireless infrastructure equipment, any of the services the enterprise could provide are unavailable until the user can leave the dead area and logically reconnect. The user must actively seek a location with a sufficient signal; finding the location where a connection can be obtained is a manual process. When a user finally locates an area to connect with the wireless carrier, the user can connect with the network to send and receive data. The user must stay in the coverage area until the data interchange is complete. See
Dead-spots are sometimes caused by weak signal strength resulting from normal propagation losses. Increasing the power of the transmitters is not a good solution in most radio systems because it increases the level of interference encountered by all other users, and degrades battery life. With television, the viewer ignores the “snow.” In voice communication systems, the users relocate themselves to a better location, or delay the communication. In portable data communications systems, the only practical solution is to retransmit the data later on.
Dead-spots are sometimes caused by multipath, the out of phase reflections of the desired signal. A system of diversity antennas is commonly used in fixed systems, but is impractical with personal equipment because the small size leaves no room for a second antenna, and if such an antenna were added, it may not have sufficient separation from the primary antenna to provide reliable diversity operation. In addition, a larger battery would be required to support diversity processing. With television, the viewer reorients the antenna to minimize the “ghosts.” In voice communication systems, the users can hear the problem occurring and relocate themselves to a better location, or delay the communication. In portable data communications systems, the only practical solution is to retransmit the data later on, hoping the user (or the source of reflections) will have moved by then to a more favorably location.
Dead-spots are sometimes caused by interference from adjacent users or adjacent cells. When an FM radio broadcast is interfered with, listeners tune to a different station. In voice communication systems, the users relocate themselves to a better location, or delay the communication—waiting for the interference to cease. In data communications systems, the only practical solutions are either to retransmit the data a little later on, or to switch to a different communications channel, if available.
All these three above-mentioned conditions lead to typical measured (and designed-to) reliability of portable communications systems of approximately 90%, i.e., 90% of the locations, 90% of the time. Public safety systems are typically designed to 95% of the locations, 95% of the time, by using diversity schemes and by increasing transmitter power—disregarding interference to adjacent systems (through a process of neighborly coordination).
e. Wireless Availability and Compatibility with Current Technology
North America has many wireless carriers, and multiple communications standards with numerous opportunities for incompatibilities. Furthermore, all carriers do not cover all geographic areas, nor have roaming agreements in these areas. The design reliability of RF propagation is generally 90%. It is difficult for the average user to contend with these issues.
f. Current Communications Model
The current wireless communications model, as shown in
The current, “On-demand” wireless communications model requires that users be connected to the wireless communications network in order to receive or send data. Users receive bandwidth from the network on an “On-demand” basis as shown in
The connection between the user's device and the Enterprise System is manually initiated, that is, initiated by the user. This model, when used in the office, presents no connection barriers to the user—the connection is always available. But the communications through wireless is of a different nature than LAN communications in the office. Thus, if a user wants to send an e-mail message through the wireless communications system, the user must have an active connection at the time the message is sent. Therefore, the user must:
The interaction between the user and the enterprise over the wireless network must be initiated by the user and take place in real time. The “On-demand” connection model over wireless connections can prove intolerable given the connection problems and the long latencies encountered sending and receiving large files over the wireless networks.
g. Security Issues
A tactic to overcome some of the problems of wireless connectivity is to enable access through multiple wireless networks. However, each wireless protocol has its own security system. In addition, that security may or may not be engaged. To overcome the multiple network security problems, an application-level security system may be required that does not rely on the wireless security system to be engaged in order to ensure secure data transfer.
h. Channel-Loading
Both average data loading and average voice loading experience predictable highs and lows during a 7-day week. When one examines loading of voice (for example) at a single cell site, however, the peaks and valleys over the course of a few moments are more severe than the average, leading to “system busy” conditions when the site is overloaded. The practice of the wireless communications industry is to provide an “acceptable” level of failed attempts, as is done in the wired telephone industry. The net effect of this is to delay the traffic until later, when channels open up. In voice systems this works quite well as users sporadically try later, or abandon the call altogether. In data systems, the equipment is programmed to retry again, colliding with other similar units, actually limiting throughput below optimum. Eventually all the traffic is handled (or abandoned), but with unhappy users and much delay. This resulting latency is often greater than the patience of the user.
Any delay leads to user dissatisfaction, which increases churn (switching carriers). The carrier's alternative to handle the traffic is to build additional infrastructure, investment that is needed perhaps only 1% of a typical week.
Since information is more valuable when delivered in a timely manner, trying to provide the bandwidth to users in real time leads to building expensive reserve infrastructure just to provide connections during peak periods. The higher the peaks relative to overall average usage, the greater the expense to the carrier to provide the reserve infrastructure. Reserve infrastructure does not produce revenue most of the time; thus any way the carrier can reduce the reserve while still providing an acceptable level of service will lower infrastructure costs to the carrier. Shifting as much usage from an “On-demand” to an “As-available” basis reduces peak demand and thus reduces the need for reserve infrastructure.
i. High Cost of “On-Demand” Airtime
A typical digital voice call transmits 8 kbps (8000 bits per second) of airtime. The cellular (or data system) carrier typically receives $0.11 for a minute of voice airtime during the workday, passing 60 kilobytes (480 kilobits) in a minute. A data file could be downloaded at that speed (or many times that speed, depending on the system). With error correction and redundant coding, this allows downloading a file of perhaps 30 kilobytes—equivalent to an average-sized e-mail—also for $0.11. A three megabyte file attachment would cost approximately $11.
These costs will quickly add up as users download/upload presentations and other large attachments, or view web pages. The carrier would prefer to remain revenue-neutral between data and voice, and is not inclined to reduce the charge for data. However, the carrier would be willing to provide reduced charges for delivering ‘deferrable’ data packets (using “As-available” airtime) as possible with this invention, since it would allow the carrier to more efficiently utilize its existing infrastructure, just as they offer discount pricing for nights and weekends. Users, however, are not interested in waiting for their information.
“On-demand” connections force infrastructure builders to build a network to handle peak usage. This significantly increases costs to both the user and the provider. As discussed above, bandwidth usage on an “As-available” basis reduces infrastructure requirements and thus a provider could sell bandwidth to “As-available” users at a much lower cost than to “On-demand” users.
(Building infrastructure to handle peak usage levels means that wireless access points are unused much of the time. Building an infrastructure to handle average usage would mean that a provider could build a less costly and lower priced infrastructure.)
j. Problematic Inquiry/Response Technique:
To receive information from a database, the mobile worker with today's systems must first structure up an inquiry. This is accomplished by inputting what is desired with a stylus, keypad or thumb-pad. The inquiry is then transmitted in to the enterprise. With the 2.5 G systems available in 2003, the speed of transmission is approximately equal to dial-up speed. After a short delay, and assuming off-peak time of day, the response is returned to the user's device, at dial-up speed.
At this point the mobile worker has spent considerable time and received little information. This is especially true if the request was to confirm availability, and the response was: “None.” The mobile worker must now determine what might be a substitute, and then again structure up an inquiry to request availability.
The length of the response can also be an issue if, for example, the information being returned is a medical record and the paramedic has to wait for the transmission to finish before administering a critical medication. Similarly, if repair information is being downloaded, the duration of the transmission may seem excessive to the customer who is paying the repair person by the hour.
Since information is transmitted too slowly, and because it is difficult and time consuming to structure an inquiry, a possibly better alternative that can be used is to deliver as much information as possible “in advance.”
k. Low Throughput on WWANs
Current “2.5 G” generation WWANs provide connections approximating dial-up speed. Future “3 G” third generation promise speeds greater than 384 kbps, approximating a home DSL connection (somewhat slower than a home cable modem). However, a connection that fast would require that the wireless carrier allocate almost all the available bandwidth to one user. In reality, maximum connection speeds will likely be no more than 140 kbps and most frequently near 70 kbps, and this estimate does not factor in overall throughput reductions that would be created by poor and dropped connections.
l. Conclusion
As a result of the many limitations described below, communicating through existing wireless systems in real-time can be daunting for many users.
In a first principal aspect, the present invention provides a sync-seeking system comprising a central server and a portable server. The central server stores a central-server copy of original data and can accumulate central-server changes to the central-server copy. The portable server stores a portable-server copy of the original data and can accumulate portable-server changes to the portable-server copy. The central server and portable server engage in peer-to-peer communication, via at least one wireless network, to exchange any central-server changes that have been accumulated by the central server and any portable-server changes that have been accumulated by the portable server until the central server and the portable server each store a copy of synchronized data.
In a second principal aspect, the present invention provides a sync-seeking system comprising a central server, a first portable server, and a second portable server. The central server stores a central-server copy of shared data and can accumulate central-server changes to said central-server copy. The first portable server stores a first-portable-server copy of the shared data and can accumulate first-portable-server changes to the first-portable-server copy. The second portable server stores a second-portable-server copy of the shared data and can accumulate second-portable-server changes to the second-portable-server copy. The central server and the first portable server engage in peer-to-peer communication, via at least one wireless network, to exchange any central-server changes that have been accumulated by the central server and any first-portable-server changes that have been accumulated by the first portable server, and the central server and the second portable server engage in peer-to-peer communication, via at least one wireless network, to exchange any central-server changes that have been accumulated by the central server and any second-portable-server changes that have been accumulated by the second portable server, until the central server, first portable server, and second portable server each store a copy of synchronized data.
In a third principle aspect, the present invention provides a method for synchronizing a central server and a portable server. In accordance with the method, the central server collects central-server information for delivery to the portable server, and the portable server collects portable-server information for delivery to the central server. The portable server establishes a wireless connection with at least one wireless network. The central server and the portable server establish a logical connection via the at least one wireless network. The central server and the portable server engage in peer-to-peer communication, via the logical connection, wherein the central server transfers the central-server information to the portable server and the portable server transfers the portable-server information to the central server.
In a fourth principle aspect, the present invention provides a sync-seeking system comprising a portable server, a first central server, and a second central server. The portable server stores a first-portable-server copy of first original data and a second-portable-server copy of second original data and can accumulate first-portable-server changes to the first-portable-server copy and second-portable-server changes to the second-portable-server copy. The first central server stores a first-central-server copy of the first original data and can accumulate first-central-server changes to the first-central-server copy. The second central server stores a second-central-server copy of the second original data and can accumulate second-central-server changes to the second-central-server copy. The first central server and the portable server engage in peer-to-peer communication, via at least one wireless network, to exchange any first-central-server changes that have been accumulated by the first central server and any first-portable-server changes that have been accumulated by the portable server until the first central server and the portable server each store a copy of first synchronized data that corresponds to the first original data as modified by the any first-central-server changes and the any first-portable-server changes. The second central server and the portable server engage in peer-to-peer communication, via at least one wireless network, to exchange any second-central-server changes that have been accumulated by the second central server and any second-portable-server changes that have been accumulated by the portable server until the second central server and the portable server each store a copy of second synchronized data that corresponds to the second original data as modified by the any second-central-server changes and the any second-portable-server changes.
1. Overview
a. Purpose
One purpose of this invention is to increase both the productivity of mobile workers (while saving money) and the economic and technical viability of wireless data communications. This technology can provide users with office-like data communications capability, as if using a wired system, but using instead the wireless communications infrastructure.
Potential benefits include: (1) reducing the delay between a user's request for information and the fulfillment of that need; (2) reducing the transaction load on the individual for predefined information and/or predictable transactions, (3) delivering copies of web seminars, analyst meetings, subscription content, and similar fare, written or audio/visual graphic and other media, for use at a later time by the owner, if desired; and (4) providing Internet, intranet and database ‘replication’ from and onto the Portable-Server, consolidating a person's resources in their pocket.
Exemplary considerations can include:
b. Mobile Wireless Data Market Dynamics
Cost saving and productivity increases garnered by not tethering a mobile worker to his or her desk are driving the market for wireless information. As evidenced with PCs and cell-phones, companies embrace technologies that allow leaps in productivity.
Business users were the earliest drivers of wireless voice communication and will become the earliest drivers of the wireless data services, as it becomes increasingly more valuable to be able to send and receive e-mail, check inventory, and access corporate information from remote locations. Many business people who use wireless phones today and do not currently have wireless data access, are likely to add this feature in the near future, making wireless information access a high growth arena in the wireless industry.
Wireless data can help businesses, giving sales professionals the ability to access catalog listings, customer history, product specifications, inventory levels, shipping data and other key information—while en route to a client's office. Traveling executives and managers want instant access to critical corporate information from company databases. The greatest appetite for these services will probably come from workers in the field.
Businesses increasingly communicate via electronic means—E-mail has become a way of life for many mobile workers; they use it day in and day out to communicate with customers, suppliers, colleagues, and superiors. While e-mail represents a major wireless data opportunity, having e-mail access everywhere does not solve wireless corporate data requirements. As e-mail becomes increasingly prevalent, so do attachments. E-mail becomes the “Post-it” note attached to the face of a document (attachment) that needs immediate attention. Just as wireless phones revolutionized the verbal communication needs of businesses and individuals, wireless data access will revolutionize the concept of the mobile office. True productivity gains will be realized when workers only need to return to an office for social reasons—not to get a file or send a message.
WWAN wireless carriers such as AT&T Wireless, Nextel, Cingular, Sprint PCS, T-Mobile (formerly called Voice Stream), and Verizon already have much of the capabilities currently in place to provide wireless data service to support this invention. These companies all have operating wireless telephone networks that are underutilized except during peak times. This invention, called WIPSS (Wireless Intelligent Portable Server System), offers these companies the ability to level their traffic loading because WIPSS data traffic can be given a lower priority than voice; i.e., at peak times data transmissions can be delayed slightly until channel loading permits. Also, data can also be sent over channels normally reserved for roamers; this data traffic could be suspended if a channel is needed for a roamer, then resumed when the voice traffic is over. Actually, WIPSS tolerance for “ruthless preemption” could allow more channel reserve for roamers (helping to eliminate dropped calls) while increasing total traffic (WIPSS and voice), with little or no additional investment in infrastructure to support peak usage.
Wireless carriers also have the capability to provide Wireless-LAN networks or negotiate cost-effective roaming agreements with others. Several carriers have announced their intention to create nationwide WLAN networks; possibly these will evolve similarly to cellular networks and roaming agreements will be created. The dual functionality of WIPSS (WLAN and WWAN connectivity) allows the carriers to provide functionality and establishing a base of billing for their fledging WLAN networks.
WIPSS technology addresses numerous opportunities in its implementation and usage. The end-user market could consist of millions of ‘mobile workers’ worldwide across four primary classifications:
In addition, there is a large potential market for consumer use. Our new wireless data communications technology addresses the problems limiting the acceptance of wireless data among mobile workers, as shown in Table 1, and is designed to provide to mobile workers, at an affordable price, nearly identical information capabilities to that office workers now enjoy.
2. Wireless Intelligent Portable-Server System (WIPSS) Technology
This technology is specifically targeted to mobile workers, and to those who normally work out of an office environment but have an occasional need for quick access to large amounts of information. This technology can enable high volume, two-way data access through wireless data communications channels. Furthermore, users of this technology may experience access latencies not much greater than experienced through a local area network.
Current approaches have users interact with enterprise servers while connected to the wireless network. Users experience the latencies and all other problems of the wireless network while attempting to perform their tasks.
To address latency problems, we provide a new model of distributed computing, and the methods to support this new model.
The innovative approach in this document describes methods that can enable the user to send and receive data without with the latencies of the WWAN or WLAN networks. A new device is proposed, called a Portable-Server (PS), and another device called a Central-Server (CS). The CS and PS work through the problems of wireless connections in the background so as to spare the user the delays, difficulties and problems of the wireless connection. The CS and PS exchange data through the wireless network on an “As-available” basis and in a timely manner. The user can then access the data from the PS in the same, nearly instantaneous manner as would be available from a server over a wired, local area network (LAN) connection.
This invention also provides a new protocol, called “POST,” for communications initiation by often-disconnected devices. POST is an acronym for Paired Opportunistic Swap Technology. POST uses Sync-Seeking servers with an intelligent agent to support an individual mobile user, so that each server is in the best possible position to serve the mobile user when communications are established. In the POST approach, each server in the pair collects information in a queue for exchange with the other server in the pair when a wireless connection becomes available. Data—e-mail, documents, programs, file and database updates, etc.—are “POSTed” to the user's PS through the wireless network on an on-going basis. The user interacts with the data once received in its entirety. (The PS has large storage capability, similar to an office computer.) Furthermore, sending data back through the wireless network, the user is not required to directly interact with the WWAN or WLAN, and yet the data travels automatically to its destination through the wireless network.
To explain various aspects of this invention, we define exemplary domains and describe exemplary methods. The domains described will be: The logical equivalence between the PS and CS, the innovative aspects of this conceptual change in computing and communications, and the business problem that using this new concept will solve. In its exemplary embodiments, the invention may make use of the following methods:
a. Logical Equivalence
This system consists of a PS connected to one or a plurality of wireless communications networks. The system also consists of software that operates on a typically stationary CS. A critical feature of this technology is that the PS is a logical extension of the CS (and vice versa).
At rest, the PS has data that is essentially a duplicate image of data on a designated logical portion of the CS. Any update to the affected data in the CS will be reflected to the Portable-Server. Furthermore, any update to data on the PS will be replicated back to the Central-Server. The Central-Servers and Portable-Servers will be continuously attempting to be equivalent.
Physically, the CS may be a stand-alone device, or part of the enterprise system. Logically, the CS may include management software to:
In its most preferred embodiments, the invention is:
b. Distributing a Central-Server onto Portable-Servers
The solution described herein introduces the concept of providing the user with a PS computer that functions as a logical equivalent of a subset of the CS computer. Moreover, the WIPSS communications model is designed to handle unreliable wireless communications. In particular, disparities between the servers that may develop when they are unconnected may be corrected when they are re-connected.
c. Connecting Sync-Seeking Servers over Wireless Connections
This invention provides a solution to problems with wireless connections and provides logical methods for utilizing the benefits of wireless technology. In particular, the invention adapts to discontinuous wireless connections between the servers.
Some solution providers have dispensed with having the user connect with a WWAN to synchronize their files with the server. In these connection models, the user must connect to the enterprise locally through an office LAN connection. Special software then synchronizes the enterprise with the computer used in the field. However, in this model the user must make a special trip to a fixed location in order to connect with the enterprise.
As shown in
The WIPSS connection model can utilize most available wireless data networks. In the WIPSS connection model, the user carries a PS that is logically equivalent to a segment of the CS and thus:
The CS typically has an Internet IP address that is permanent. The PS typically has a constantly changing address (e.g., a DHCP network address) based on the technology in use at the carrier. Each time the connection between the PS and the carrier's network drops, the PS will likely be reassigned to a new network address. In addition, the PS could be assigned two temporary network addresses simultaneously; one address could be a WWAN address and the other a WLAN address. The PS could also signal to the CS the address that is “Active” and the one that is “Standby.” More detail regarding these connection methods will be discussed in a later section.
The WIPSS connection model involves use of a private, inter-server messaging system that uses peer-to-peer communications with a private messaging protocol within a standard data communications protocol. Thus we are able to use public data communications network such as the Internet (that uses TCP/IP and UDP), but send encrypted private messages between the Sync-Seeking servers. Furthermore, WIPSS communications model can be connection independent, so that it does not matter if a connection is made through a WWAN or WLAN connection—in series or in parallel. The communications model is designed to enable the following types of data flow no matter the path:
Connection breaks involve secure reestablishment of communications (because of rolling codes used for asymmetrical encryption keys) with the most remote possibility of spoofing or breaking into the communications system.
In the WIPSS connection model, establishment of a connection between the Sync-Seeking servers takes place in the manner shown in Table 2, from the fully disconnected state.
This invention is intended to be transport-network neutral and protocol neutral. Transport of data can be through the Internet or through a private network. The methods described do not require use of a particular access or transport protocol in order to function properly.
In addition to that shown on the state diagrams, the CS is responsible for interfacing with and tracking changes in outside data repositories, while the PS handles Display Devices.
As will be discussed, the peer processes are also in communication and have responsibility for overall paired system “POSTing,” but at a higher level. This is discussed in a later section.
d. Wireless Access Selection Methods
This invention can use redundant wireless data communications methods. More than one wireless channel can be used to transfer data. Communication data between the CS and PS can flow through its WLAN channel, and/or a WWAN channel, or may use a future wireless telephone or satellite data network access standard (or even a wire-line connection). Preferably, the PS manages the wireless connection, initiating the connection with the wireless network and attempting to reconnect with it when a wireless connection has been dropped, selecting between possible networks based on things like price of the choices, speed of the choices, amount of information queued for transfer (in each direction), amount of a given file left to be transferred, predefined priority level (reference material such as an instruction manual update vs. transactional material such as changing inventory levels), if an e-mail has a “TO:” vs. a “CC:” designation, user preferences, need for Instant Messaging, need for on-line, On-demand (pipeline mode) access, etc. This can be further modified by cost considerations, especially when additional connection choices exist, an example of which is shown in Table 3. As illustrated by Table 3, weighted values could be used, depending on the user or system preferences, and availability, to continually decide the best choice or choices. Because queues develop when the peered servers are not connected, the Selection Score can change rapidly, and the advantage of using more than one channel in parallel may look more attractive. It is important that WIPSS, as provisioned by the user, consider not only the absolute cost, but also the time-value of delay, the transmission speed available, and the file and queue sizes.
The PS and CS have the ability to transmit files to one another based on link price, file size, file importance, and the time the user requires the file. Optionally, the user of the PS may set preferences that a certain file must be transferred at any cost within a certain amount of time. Or the user may determine that a file should be replicated within a certain amount of time or days for a minimal amount of money. The cost associated with passing files across the channel is dependent upon the cost of the channel, the speed of the channel, and the size of the file. For each file there will be multiple “Link costs.” The link costs are described by:
Total_File_Link_#_upload_cost=price_per_second*file_size_in_bits/speed_in_bits_per_second.
WIPSS can perform decisions on which link(s) or channel(s) to utilize for a given file, and the time at which to propagate the file, based on the preferences that the user sets for a file.
This optional ability for the user to set preferences for the files enables the system to perform specifically to the users needs, and allows the user to set relative values to the data that is stored on the CS and PS systems.
e. Primary Channel Communications Methods
There are several possible methods to select the appropriate communications channel, and there are various methods for choosing, connecting, reconnecting and switching between channels. One of these methods is discussed below, although other methods could be used.
The methods for channel selection described in this section involve the designation of a primary channel. We define the methods for dealing with this process in the details below. We discuss first, when the WLAN is the primary channel what the operational methods will be, and second, when the WWAN is the primary channel. In these embodiments, we describe a situation where the WWAN channel is more widely available, but slower, than the WLAN channel which is faster, but has more limited in range and availability. (Although we discuss the selection between two channels, these methods can be extended to more than two wireless channels.)
WLAN Primary Channel
Where the faster, but shorter range, WLAN is the primary channel and WWAN is the secondary channel:
If the WWAN connection is lost, no immediate attempt will be made to reconnect when connection to the WLAN is established. However, if communications with both channels have been lost, attempts will be made to reestablish this connection:
In this case, the wider ranging, but slower WWAN is the primary channel. If WWAN is the primary channel and the Wireless LAN is the secondary channel, then, when a WLAN is detected:
In this model, there is no primary channel and each channel is dealt with equally. At any given time, one channel may be designated as Active, and the other as Standby. A connected channel will always be designated as Active, but the Standby channel may be connected or disconnected. Active/Standby designations become situationally dependent.
Co-Equal/Situation Dependant Models
Lowest Price Model
Higher Speed Model
First Available Channel Model
The Active/Standby capability could be further refined by the capability to turn off the Portable-Server's send capability. The PS would only receive information and would not send acknowledgments until the send capability would be allowed to function.
These methods address a number of inherent wireless problems by utilizing more than one possible wireless connection, which increases chances of accessing available data transport:
f. Lowest Purchase Price Model/Lowest Cost To Provide Model
Rationale: Most data communication in WIPSS model does not require “On-demand” service from a wireless communications carrier. The provider can allocate a communications channel when resource demand is low, and when demand is high, he can shut down the channel allocated to WIPSS data.
Wireless network providers know that a communications channel exists for a moment in time, and if an available channel-moment is not used, it is lost forever. The wireless network provider's preference is to sell that channel-moment to an “On-demand” customer, a person who just pushed TALK on their phone or computer. Therefore, if a carrier has a channel-moment available, and has no paying customer ‘asking’ to use it, it has zero value for that moment. That is the same value as an empty airplane seat as they close the doors for takeoff. WIPSS communications model uses those ‘empty seats’ and enables wireless network providers to offer bandwidth to users in the most effective manner. Each channel-moment can be used to handle a WIPSS packet. Network resources can be planned more based on overall daytime demand instead of peak demand.
(Providing resources on the basis of peak demand forces network planners to spend uneconomically for resources, while if resources could be put in place more on the basis of overall demand on a per cell-site and per minute basis, resources can be more economically planned for. Furthermore, network providers could produce additional revenue without putting in additional resources given that their network resources were put in place on the basis of peak demand. This model will allow network providers additional revenue at nearly no cost to them.)
The lowest price model can be further elaborated by:
g. Server Couplet—Two Halves of One Logical Server
As shown in
h. Sync-Seeking System
That portion of the CS related to a specific PS, together with the PS, operate through attempting to maintain equivalency between the respective data sources. A change in data that occurs in one server generates the processes to propagate that change to the other server.
At the two ends of this paired server arrangement are peer processes that communicate to maintain communication and data synchrony. The peer processes manage communication synchrony using the methods discussed above. It also manages data synchrony using the methods and capabilities described below.
The method of the paired peer processes—one process in the PS and one peer process for each PS that the CS supports—may perform the following services for the system:
i. Synchronous Database
Databases may be established in the CS and the Portable-Servers. Processes on each side detect any changes to the data in either database, which is reported to the peer process on the affected server side. That peer process then sets up a data transmission immediately, or through scheduling, with its peer on the other side. Processes that detect changes to the data—that is, detect asynchronies—communicate through the peer process. This enables different types of databases to communicate to each other and their contents to remain in sync.
j Synchronous File System
The file system procedure is similar to that of the database, with the exception that the data is organized in a file system. The peer to peer processes enables data replication between data stored in a file system in one Sync-Seeking server and in a data system in the other side of the Sync-Seeking server. The “data system” can include a corresponding standard file system or a data base.
k. Synchronous E-mail
E-mail operates in a similar manner as the synchronous database. Alternately, the PS could operate directly with the mail host.
l. Pipeline Mode
This invention can include the capability to enable the user to connect in real time through the wireless system. The Sync-Seeking server capabilities, other than security and encryption, could essentially be bypassed. For example, if a user were connected to the Internet web using an HTML browser, the services of the Sync-Seeking servers would be unnecessary. In this case, when this Pipeline capability is engaged, the Sync-Seeking server capabilities are not engaged. Similarly, Instant Messaging could be handled this way. The wireless carrier would recognize this traffic as “On-demand” and process (and invoice) accordingly. See also Table 3.
m. Distributed Units; Autonomous Operation
The PS units operate autonomously in that they normally do not require user intervention. The PS operates in “POST” operation with the Central-Server.
The WIPSS system not only looks at the cost per second of the transmission link, but also accounts for the file size and transmission speed. Additionally, the value of different files is important. The WIPSS system has the ability make decisions based on upload/download cost and user set preferences. Different files cost more to transmit on different links and the intelligence of the WIPSS systems makes it possible for the user to utilize the most appropriate transmission means for each file.
The WIPSS system provides notification to the varying display devices of CS and PS status, wherein each PS can relay information to display devices in a proprietary format, such that the display device, while utilizing known software, can interpret and communicate to the user the status of the system.
n. Integration with Other Enterprise System Services
This technology can be integrated with other enterprise system services and other computers. Usual methods for performing that integration are not detailed herein.
The WIPSS system enables a user to access the CS via a web-based (HTML/HTTP) interface enabling the user to utilize the CS as a security proxy and application proxy to access otherwise private systems such as secure corporate or enterprise network systems. This is used for the purposes of initial provisioning, re-provisioning, and other purposes. (For example, utilizing CS to CS intercommunication and “autonomous configuration” could uniquely enable the WIPSS system to allow users to migrate between carrier/operator solutions. In other words, a user could subscribe to a new service on a different operator's system and utilize this feature to transfer his or her data.)
o. Inter-Server Data Security
As discussed earlier, data transfers are initiated through Sync-Seeking processes. A change in data—an updated file or database record, an e-mail sent or received—produces a state in the system to initiate and complete a data transfer to the Sync-Seeking server. In addition, data security—authentication and encryption—operates in a similar manner as well, and as such, will be included in the description.
Authentication and encryption techniques may involve the following:
p. Expanded Functionality from ‘Peered’ Central-Servers
Central-Servers may be instructed to seek information from other Central-Servers, thereby learning things of importance to owners of Portable-Servers. A specific example is the ability to share the individual “Transmitter Site Knowledge Bases”(TSKB) as new sites are discovered and existing sites removed from service. Each Portable-Server refers to its TSKB when looking to establish communications. If the PS had no idea of where it might be, although it knows where it was recently, it would have to initiate a random search of both cellular and WLAN channels. Normally, the PS knows where it has been recently and can ‘learn’ its approximate location from inquiring of the cellular system, (cellular systems often provide coordinates as learned from time-of-arrival calculations) then search a limited number of choices. This limits the searching that must otherwise be done to establish communications. The spontaneous peer to peer information sharing ability of Central-Servers may also be used for distribution of files, thereby offloading the enterprise system.
Finding Wireless LAN connections is more difficult than finding WWAN connections, and uses more battery power. This is because WLAN access points typically have low RF output power and hence, limited range of operation. Also, there are more RF channels to be searched. The WIPSS PS unit improves the probability and speed of finding an access point by maintaining a database of possible network choices, thereby saving time and power consumption over that used by a random search. This is advantageous, but is multiplied in effect by having the Central-Servers share the knowledge learned by their respective Portable-Servers. In this manner, each PS has a database of possible choices as complete as any other in the world. As knowledge is assimilated by one PS, it is learned by all.
q. Discussion of Advantages
The WIPSS solution can make use of inexpensive airtime. This is because the carrier has the right to “defer” the packets until excess capacity is available. This is similar to filling empty seats on an airplane with “standby” passengers. The reason this is achievable is that the system breaks each message up into packets that are routed somewhat independently to the other Sync-Seeking server. The reason this is acceptable is that no human at the other end is waiting for those packets. Not only can the packets be deferred, but they can also be spread over time. This increases channel usage in a multi-channel communications system, without increasing the latency as seen by the users. This technique of separating messages into smaller packets and sending these packets through the network during the breaks in normal voice messages, hides delays introduced by the process, so that they are not noticeable to the user, because the user sees only the complete restored message.
An additional benefit to the carrier would be the lack of necessity to provide seamless, roaming coverage. For example, currently wireless networks must be able to hand-off connections between access points during a call without dropping the call. Anyone who has ever made a wireless call while moving has noted that this system operates correctly most of the time, but not every time. The WWAN carriers have devoted significant resources to making and continuing to make this system operate. A side benefit of WIPSS “As-available” technology will be that carriers need not provide seamless roaming since the user is usually not directly connected to the wireless network, but is connected through a Portable-Server; the CS/PS connection can be thought of to exist at the “packet” level, rather than “session” level. The user would probably never be aware of a connection break. When a wireless network connection break would occur, WIPSS technology would immediately and automatically seek a new connection, obviating the need for seamless roaming. Users would experience an “On-demand” continuous connection with their Portable-Server, but the carriers need provide only “As-available” airtime.
In preferred embodiments, the solution will appear as fast as, or quicker than, any other approach. This is because (1) the Portable-Server is always looking for one or more networks to communicate over, (2) information is pre-sent in anticipation of its need, and (3) the slight delay caused by the deferrable nature of the transmissions will never be ‘seen’ by the end-user.
The technique of pre-sending (pre-positioning) information on the Portable-Server goes far beyond simple “Pre-caching” used on the Internet today to put web servers at the “edge” of the Internet so as to deliver web pages faster. In the WIPSS implementation, it is the power of the Central-Server seeking out specific information of usefulness to the user of the Portable-Server, and pre-sending that information to the specific person when inexpensive air-time is available, that makes the system work so well and so inexpensively. The system is moving massive amounts of data at very low cost because it is moving it in anticipation of its need using otherwise wasted airtime-moments. The system is also better in that it works in both directions. In the inbound (toward enterprise) direction, files changes are sent from the PS to CS without the requirement to first “log-in” to the enterprise system or application that handles the specific data. The CS subsequently “Logs-in” and updates the enterprise system or application.
The WIPSS solution allows the powerful agents to automate much of a user's communications requirements. The WIPSS “POST” technique can go beyond “Pull,” “Push,” “Dock,” and Internet FTP techniques to provide reliable delivery in the difficult RF environment. The POST design assumes connections are sporadic, and provides queues based on specific user needs. When a connection occurs, the POST quickly executes its processes on both Sync-Seeking servers (Portable-Server and Central-Server). See
In the event a user needs to Instant Message or ‘surf’ the Internet, POST switches to a real-time connection (pipeline) mode. POST is IM-aware: Instant Messaging requires that once one is connected, that “presence” be continually communicated to one's “buddies.” POST confirms not only that the Portable-Server is connected to the Central-Server, but also that a laptop or other display device is turned on and linked to the Portable-Server, i.e., a human is present. The corresponding process on the CS signals lack of presence whenever it loses communications with the Portable-Server, or is told by the Portable-Server that no display device is active.
Establishing “Instant Messaging” with often disconnected units, wherein the base unit (Central-Server) acts as a stand-in for the mobile unit and logs in and out of the Instant Messaging Server, will follow rules similar to below:
The use of a Central-Server solves many of the problems with corporate use of Instant Messaging, for example, the required archival logging of traffic transfer to and from various IM systems, enforcing security restrictions with respect to sending attachments, encryption, etc.
Some of the various modes of operation are shown in Table 4.
This algorithm can be further modified by cost considerations, especially when additional connection choices exist. For example, one might consider if in a ‘home’ cellular (WWAN) area or ‘roaming’ cellular area; is a WLAN available that is free or is a subscription required (and if so, are we subscriber?). Also, the traffic queue depth will likely be a consideration.
The WIPSS solution has increased reliability over the RF channels because of the extensive use of diversity techniques: (1) two separate networks are used, using different frequencies and modulation formats over separate antennas; (2) by sending information opportunistically in anticipation of its later need, we are using time as a diversity technique; and (3) we are anticipating the owner of the Portable-Server will move over time to a different (hopefully better) location, resulting in space/location diversity.
We call this simultaneous use of multiple independent diversity techniques “Multiple Orthogonal Diversity.” This is a technique of continuously attempting, by simultaneous use of three or more of the following, to maintain wireless logical connections and improve its overall reliability:
The WIPSS solution can also extend battery life because no display is used—a major user of power. Also, the use of the self-learning Transmission Site Knowledge Base (TSKB) will allow conservation of transmitter power, and increase throughput when high-speed facilities are available. The TSKB makes use of location information learned from the cellular system itself (typically from time-of-arrival calculations) and/or GPS information from an onboard or nearby GPS unit. The TSKB is updated regularly based on queries by the Central-Server of other Central-Servers, each of which is learning about possible transmitter sites from its respective Portable-Servers, as these sites are observed by the Portable-Server as the units travel around.
This solution addresses all known security issues through the use several techniques: Dual encryption is used: a form of public-key encryption (PGP, PKI, ViaQuo, or similar) is used for end-to-end encryption between the enterprise and the Display Device, and a special additional crypto system for the over-the-air links between Central-Server and PS and from Portable-Server to display device.
WIPSS could take responsibility for supplying and enforcing the proper authentication and encryption techniques because the users cannot be counted upon to do it. Ideally, the enterprise would send out files encoded with the Public Key of the intended recipient, which could properly be decoded only by display devices owned and controlled by the recipient. (Public Key could provide the desirable ‘non-repudiation’ feature.) The Central-Server could look for file changes by comparing hashes of files.
The over-the-air link between paired servers is the most vulnerable to attack, because insiders have access to much clear-text and corresponding over-the-air cipher-text. Since WIPSS cannot depend on the enterprise to correctly encrypt all files, nor count on any over-the-air facility, the paired servers could advantageously provide authentication and privacy.
A wireless communications model can beneficially use security methods designed to:
Because the Portable-Server and CS authenticate each other, the resulting data may be safely transferred through the firewall into and out of the enterprise. As an additional security feature, the enterprise's Chief Information Officer (CIO) could be able to remotely erase files on a Portable-Server. See
Note: the PS and the CS are usually “connected” in the background without using airtime. The WWAN carrier and WLAN equipment each typically maintain logical connection status with all mobile units without charge. (This is how a cellular system knows where you are.) These carriers also maintain a logical connection from their terminus to the Central-Server, also without charge. (The wireless carrier maintains an IP address for the PS without charging airtime.) Logically, the communication channel can always be “on,” that is, WEPSS is in constant communication with the carrier's network, but there is no charge. During quiet periods—when no data is being exchanged—the PS will periodically send a short packet to the CS indicating that the PS is connected and operational. The CS and PS verify each other's operational status using trivial amounts of airtime. There is a charge for this. WWAN wireless packet data is charged based on kilobytes transferred through the network. It is not charged on the basis of an “airtime” connection charge, as with voice. Publicly accessible WLANs generally charge a fixed price for unlimited usage over a period of time, e.g., a monthly charge.
One purpose of the Central-Server is to “look like” the user to the various file servers the user is authorized to access, i.e., the file server should believe the user has logged-in from his or her computer, and is requesting information that the user is entitled to access.
The following are exemplary types of users:
Example of the later user type: Two people form a PR business, consulting to disparate clients across the country. They work out of their respective homes, and travel extensively. Client materials are shared. Each partner would sign up for WRPSS at their local cellular carrier, take the unit home with them, and then provision themselves for access to their home-office computer, selected directories on their partner's home-office computer, and certain Internet subscriptions and other resources. Now whenever and wherever they turn on a laptop or PDA, they would each see an up-to-date listing of all shared files, as if they were sitting next to each other. They could review and comment on each other's proposals and PR plans. They could have a common contact list, and would have instant access to each other's schedules—to set-up joint customer visits or calls. They would now have a virtual office they share, and a virtual file server they share.
All four exemplary types of users listed above can achieve the objective of duplicating the office experience when away from the office. The CS could be physically located either within the enterprise firewall, or outside. Table 5 shows four combinations of ownership and location.
The PS and CS both provide billing information to a depository so that appropriate sharing of revenue can be done between the providers and users of the various wireless networks. The sameness of the data provided is a validation that no unit is attempting to spoof the identity of a PS or CS. This also provides confidence to the providers of airtime and other services that the billing information they are receiving is correct. Previously no customer premise equipment could be relied upon to provide its own billing information; WIPSS makes this possible, saving the various carriers and service providers the expense of installing separate systems for tracking these very small transactions.
In a similar way, the PSs can assimilate the learned knowledge of other PSs through their respective CSs. When a PS acquires data through its operation, it passes that data to its CS. The CSs share certain data among themselves and shared data base repositories, so that what one “knows” they all know. The data is passed to all other PSs from their paired CS, and the local knowledge base updated. This behavior of Central-Servers, learning from one another by updating databases of shared knowledge, and then passing the knowledge on to the PSs, provides a powerful tool for ubiquitous information dissemination. For example, individual Portable-Server units add coordinates of locations of accessible transmitters (access points) based on their field experience, as well as frequencies supported and other information that will make it easier to access and authenticate in subsequent visits. New additions are communicated to the Central-Server. The Central-Server then communicates to other Central-Servers and/or a repository database. In time, all Portable-Servers receive the updated information (or at least the part of value to them). It is the Sync-Seeking nature of the PC/CS relationship and the shared knowledge base of the CSs that enable this facility.
Specific CS/CS relationships can also be formed; it may be advantageous to split or merge CS databases as changes in situation (marriage, employment, etc.) may deem desirable.
The columns in Table 6 describe differences of results between WIPSS and other approaches for key qualities desirable to users and their sponsoring organizations.
The columns in Table 7 represent what features are available via a wireless-computing device, via a non-wireless device, and via a WIPSS.
2. Central Server (CS)
In the preferred embodiment, the CS is a separate server device that may physically exist anywhere on the Internet network, or behind the enterprise firewall. The advantage of being outside the enterprise firewall in that the CS can then access multiple enterprise systems to bring across the disparate information needs of the end-user, i.e., subscriptions, Instant Messaging, home computer, Internet broadcasts, etc., while still being able to access authorized enterprise information via VPN or other connection.
The CS has several components that support the data and security system processes. In some cases, these components have peer-to-peer communications with processes in the PS. This discussion focuses on the capabilities of the specific components shown in the CS.
Multiple PS Manager:
The Portable-Server (PS) unit may be provided as a small computer that is able to connect with various devices such as PDAs, laptop computers, set-top boxes, tablets, home computers, etc., as well as cell phones and various ancillary devices.
The PS may communicate on one or more RF networks (traditional networks as well as Mesh networks), which may be either one-way or two-way, using either its own RF resources or those of other devices. The PS may use hardware, software, and or firmware to perform its various functions, as described herein.
The PS, like the CS, initiates data transfers to the CS based on achieving equivalency. If data is added to or changed on the PS outside of the Sync-Seeking process with the CS, that will initiate a data transfer from the PS to the CS.
Network Source Manager:
Four scenarios that illustrate the operation of the system are set forth below:
Scenario 1: E-Mail Sent to CS for Delivery to a Portable-Server
E-mails that arrive at the CS will be delivered to the appropriate Portable-Server. The e-mail arrives through the I/O Manager and is transferred to Data Management & File/DB Sync-Seeking System. This process translates the e-mail address into the PS identifier and stores the e-mail with the PS identification information. Furthermore, this initiates the Sync-Seeking procedures to migrate the e-mail to the identified Portable-Server.
The Data Management & File/DB Sync-Seeking System initiates the data transfer. It queues the e-mail for transfer with the I/O Manager.
The I/O Manager delivers the e-mail as data with the delivery information to the Network Security & Sync-Seeking Peer Process. The peer processes—with its peer at the other end—manage the transmission and verification of the data to the Portable-Server. The data packet flow is managed by the Multiple Server Manager.
At the PS end, packets come through one of the connections to the Network Data Source Manager that in turn passes the data to the Portable-Server's Network Security and Sync-Seeking Peer Process for assembly and acknowledgments. The e-mail is sent to the I/O Manager that in turn sends it to the Data Management & File/DB Sync-Seeking System for storage.
Scenario 2: An Update to a File Appears on CS and the File is Shared by More than One Portable-Server
In this instance, a data transfer would be initiated when a file has been updated. In addition, more than one PS has access to that file. Therefore, the change should be migrated to each PS that has that file as part of its accessible data. In this case, the Data Management & File/DB Sync-Seeking System initiates a data transfer to each of the applicable Portable-Servers. The file information indicates every PS that has access to the file. The system can distribute the file to each PS one at a time, or can distribute the file to each PS simultaneously. The simultaneous file transfer approach is preferred because of the fragile nature of the connections from the CS to the PS.
Scenario 3: E-Mail Transfer from PS to CS with Multiple Communications Breaks, Using Both Channels to Transfer Data
An e-mail for sending has been generated in the PS; thus, the message (plus any attachments) is migrated to the CS for delivery to the mail server for propagation to the recipient(s). In this scenario, the PS will encounter multiple connection breaks and will be connected to more than one channel. All through this, the packets of the e-mail will be transmitted to the CS without intervention from the PS user.
The initiation of the e-mail transfer process is the same as in the case with the CS. However, unlike the CS, the PS manages the wireless connection. Furthermore, the PS chooses the channel over which the data will be sent (and packet acknowledgments received). That is handled by the PS's Network Data Source Manager.
As in the case of the CS, the 1/O Manager sends the e-mail for sending to the Network Security & Sync-Seeking Peer Process that in turn manages sending the data. When a connection has been established and equivalency of all peer processes attained, the process sends the e-mail in packets to the Network Data Source Manager, which in turn sends the packet through the Active channel. When a connection break occurs and the PS finds another connection channel, a reconnection procedure takes place (as discussed earlier) and resynchronization of all peer process starts by re-sending the packets beginning from the point where its peer in the CS indicated it had received the last uncorrupted packet. With each break and reconnection with the PS, the CS's Multiple PS Manager maintains continually changing addresses of the PS and can receive information about the characteristics of the new connection. This can include whether the connection is high speed WLAN or low speed WWAN connection.
The packets reach the CS, and the Multiple PS Manager notes which PS the packet comes from and routes the packet to the CS Network Security & Sync-Seeking Peer Process. This process collects the packets, verifies the completion of reception of the e-mail, and sends the completion notification to the PS through the Multiple PS Manager that routes it to the correct PS.
Scenario 4: File Update from PS to CS where More than One PS Has Access to the File
There may be situations when an update from a PS affects a file or a data base record that others can access. In this case, the update from one PS would be distributed to the other affected PS's. This is a common situation in business usage.
In this case, the update from PS 1 should be distributed to PS 2 and PS 3 as well. The update from PS 1 arrives and works its way to the CS Data Management & File/DB Sync-Seeking System. The update is integrated with the affected data. Furthermore, the system notes that PS 2 and PS 3 have access to the affected data and initiates a send to PS 2 and PS 3 of the update. Further processing may occur to determine the version of file the changes apply to, and if the changed version is not the current version available to PS 2 and PS 3, then more sophisticated change management could be initiated—perhaps by alerting PS 1 to the problem. Considering the speed of the WIPSS POST protocol, the number of such update collisions is minimized.
6. File Locking
With disconnected devices, the user interface is complicated by the desire to modify files even though not connected to the enterprise. The WEPSS approach is to allow file modification without locking files by prompting the user to the extent possible. That is, WIPSS can tell the user what is known and what is unknown. (The alternative, locking files, is poor practice since a file may be locked by a user who becomes disconnected, and would remain locked for an extended time until the system timed-out. Also, the user is not aware that his/her changes were not applied to the file.)
Examples of notifications:
Despite this challenge, the user has the advantage of using familiar applications to access familiar files.
Practically speaking, a wireless update system cannot “lock” files or file segments (or records) like wire-line systems, because of the unreliability of wireless. One could lose a connection and the system would not recognize the fact for some time, preventing access by any other user.
7. PS Linked to More than One CS
Data is often fragmented, and systems incompatible. A CS that can handle data from one enterprise system may not be able, for security reasons, to handle the data from another enterprise system. CSs may need to be localized and adapted to handle the requirements of each enterprise system rather than being able to send all relevant sources of information to a single CS. Thus, there may be a clear need for any PS to be linked to more than one CS. Also, a user may be provided with a CS by his/her employer for business purposes, but the user may also want his/her personal files and/or multimedia files stored on their PS.
Given that under these circumstances, the PS can be spoofed because the PS can be connected to more than one CS. Thus, the PS can attempt to authenticate every CS to which it is logically linked.
The fundamental system operation is similar to where the relationship between the CS and PS is 1:n. In this case, the relationship between the CS and PS is m:n. To perform this function, the PS adds a process with methods to handle multiple CS units.
A Multiple CS Manager is added to the PS to manage the multiple CS units to which the PS has been logically linked. This is shown in
The Data Management File/DB Sync-Seeking System on the PS has the same method of dealing with multiple CS systems as the CS has in dealing with multiple PS systems. On the PS, the files from each CS can be distinguished from each other because of the requirement of the logical identity between the files of the PS and CS.
8. Additional Embodiments
As noted in the original patent application, the PS can physically be integrated into a display device or a cell-phone type device. The services and the capabilities of the PS can be easily integrated into a display device. The display device could be a portable PC with a user interface and network connection capabilities to WLAN and/or a WWAN networks. Since the processes of the PS will be created using computer software, those same processes could be supported by software running on the portable PC/display device. This includes autonomous operation of the server. The operating system of the PC/display device can turn user interfaces off and on as needed and run only the Personal-Server software to save battery life, but still connect with the network(s), and possibly other display devices.
The PS appears to the user like any other server (office server). Depending upon the operating system the display device uses, the PS can determine the type of device used for display, and open files and display data in a manner to consistent with this device. Note that the Sync-Seeking server couplet can still serve up information to other display devices, despite the fact it is built into a display device. Also, this system will continue to be able to support e-mail.
The cell-phone may have a built-in PDA display device, which the PS could provide services to over the same link.
As noted above, the PS can be a stand-alone device or built into a display device.
Exemplary embodiments of the present invention have been described above. Those skilled in the art will understand, however, that changes and modifications may be made to these embodiments without departing from the true scope and spirit of the invention, which is defined by the claims.
This application claims priority on U.S. Provisional Patent Application No. 60/482,978, filed Jun. 27, 2003, which application is fully incorporated herein by reference. The embodiments disclosed herein may make use of devices disclosed in U.S. patent application Ser. No. 09/652,734 titled “Wireless Intelligent Personal Server” filed Aug. 31, 2000, which is incorporated herein by reference.
Number | Date | Country | |
---|---|---|---|
60482978 | Jun 2003 | US |