Electrical computers and digital processing systems: multicomput – Computer-to-computer session/connection establishing
Reexamination Certificate
1999-06-11
2003-04-08
Geckil, Mehmet B. (Department: 2152)
Electrical computers and digital processing systems: multicomput
Computer-to-computer session/connection establishing
C709S228000, C709S241000
Reexamination Certificate
active
06546425
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to connectivity between networked computing devices. More particularly, the present invention relates to methods and systems that transparently address the characteristics of nomadic systems, and enable existing network applications to run reliably in the associated mobile environments. Still more particularly, the invention relates to techniques and systems for providing a continuous data stream connection between intermittently-connected devices such as handheld data units and personal computing devices.
BACKGROUND AND SUMMARY OF THE INVENTION
Increasingly, companies are seeing rapid access to key information as the way to maintaining a competitive advantage. To provide immediate access to this information, mobile and other intermittently-connected computing devices are quietly and swiftly becoming an essential part of corporate networks—especially with the proliferation of inexpensive laptops and hand-held computing devices. However, integrating these nomadic devices into existing network infrastructures has created a challenge for the information manager.
Many problems in mobile networking parallel the difficulties in early local area networks (LANs) before the adoption of Ethernet. There are a variety of mobile protocols and interfaces, and because standards are just developing, there is little interoperability between systems. In addition, performance over these network technologies has been typically slow and bandwidth limited. Implementation costs to date have been high due the specialized nature of deployed systems.
Along with these issues, mobile technologies present a category of problems unto their own. Interconnects back into the main network may travel over and through a public network infrastructure, thus allowing sensitive information to possibly be tapped into. Furthermore, if any of the intermediary interconnects are via a wireless interface, the information is actually broadcast, and anyone with a similar interface can eavesdrop without much difficulty.
But, perhaps even more significantly, mobile networking has generally in the past been limited to mostly message-oriented or stateless applications—and thus has not been readily adaptable for existing or new corporate applications that use client/server, host-terminal, web-based or shared file systems models. This is because such commonly used applications need stateful sessions that employ a continuous stream of data—not just a stateless packet exchange—to work effectively and reliably.
To this end, many or most popular off-the-shelf networking applications require TCP/IP sessions, or private virtual circuits. These sessions cannot continue to function if they encounter network interruptions, nor can they tolerate roaming between networks (i.e., a change of network addresses) while established. Yet, mobile networking is, by its nature, dynamic and unreliable. Consider these common scenarios encountered in mobile networks:
Disconnected or Out of Range User
When a mobile device disconnects from a given network or loses contact (e.g., through an outage or “hole” in the coverage of a wireless interconnect), the session-oriented application running on the mobile device loses its stateful connection with its peer and ceases to operate. When the device is reattached or moves back into contact, the user must re-connect, log in again for security purposes, find the place in the application where work was left off, and possibly re-enter lost data. This reconnection process is time consuming, costly, and can be very frustrating.
Moving to a Different Network or Across a Router Boundary (Network Address Change)
Mobile networks are generally segmented for manageability purposes. But the intent of mobile devices is to allow them to roam. Roaming from one network interconnect to another can mean a change of network address. If this happens while the system is operational, the routing information must be changed for communications to continue between the associated peers. Furthermore, acquiring a new network address may require all of the previously established stateful application sessions to be terminated—again presenting the reconnection problems noted above.
Security
As mentioned before, companies need to protect critical corporate data. Off-the-shelf enterprise applications are often written with the assumption that access to the physical network is controlled (i.e., carried within cables installed inside a secure facility), and security is maintained through an additional layer of authentication and possible encryption. These assumptions have not been true in the nomadic computing world—where data is at risk for interception as it travels over public airways or public wire-line infrastructures.
SUMMARY
It would be highly desirable to provide an integrated solution that transparently addresses the characteristics of nomadic systems, and enables existing network applications to run reliably in these mobile environments.
A presently preferred exemplary embodiment of the present invention solves this problem by providing a seamless solution that extends the enterprise network, letting network managers provide mobile users with easy access to the same applications as stationary users without sacrificing reliability or centralized management. The solution combines advantages of present-day wire-line network standards with emerging mobile standards to create a solution that works with existing network applications.
In accordance with one aspect of a presently preferred exemplary embodiment of the present invention, a Mobility Management Server (MMS) coupled to the mobile interconnect maintains the state of each of any number of Mobile End Systems (MES) and handles the complex session management required to maintain persistent connections to the network and to peer application processes. If a Mobile End System becomes unreachable, suspends, or changes network address (e.g., due to roaming from one network interconnect to another), the Mobility Management Server maintains the connection to the associated peer—allowing the Mobile End System to maintain a continuous virtual connection even though it may temporarily lose its actual physical connection.
A presently preferred exemplary embodiment of the present invention also provides the following (among others) new and advantageous techniques and arrangements:
a Mobility Management Server providing user configurable session priorities for mobile clients;
per-user mobile policy management for managing consumption of network resources;
a roaming methodology making use of the industry standard Dynamic Host Configuration Protocol (DHCP) in coordination with a Mobility Management Server;
automatic system removal of unreliable datagrams based on user configurable timeouts; and
automatic system removal of unreliable datagrams based on user configurable retries.
In more detail, a presently preferred exemplary embodiment of the present invention in one of its aspects provides a Mobility Management Server that is coupled to the mobile interconnect (network). The Mobility Management Server maintains the state of each of any number of Mobile End Systems and handles the complex session management required to maintain persistent connections to the network and to other processes (e.g., running on other network-based peer systems). If a Mobile End System becomes unreachable, suspends, or changes network address (e.g., due to roaming from one network interconnect to another), the Mobility Management Server maintains the connection to the associated peer, by acknowledging receipt of data and queuing requests. This proxying by the Mobility Management Server allows the application on the Mobile End System to maintain a continuous connection even though it may temporarily lose its physical connection to a specific network medium.
In accordance with another aspect of a presently preferred exemplary embodiment of the present invention, a Mobility Management Server manages addresses for Mobile End Systems. Each Mobile End System is provided with a pr
Hanson Aaron D.
Menn Anatoly
Olson Erik D.
Savarese Joseph T.
Sturniolo Emil A.
Geckil Mehmet B.
Netmotion Wireless, Inc.
Nixon & Vanderhye P.C.
LandOfFree
Method and apparatus for providing mobile and other... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for providing mobile and other..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for providing mobile and other... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3109559