초록 ▼

A hierarchical communication system, arranged in a spanning tree configuration, is described in which wired and wireless communication networks exhibiting substantially different characteristics are employed in an overall scheme to link portable or mobile computing devices. Copies of data, program c

A hierarchical communication system, arranged in a spanning tree configuration, is described in which wired and wireless communication networks exhibiting substantially different characteristics are employed in an overall scheme to link portable or mobile computing devices. Copies of data, program code and processing resources are migrated from their source toward requesting destinations based on request frequency, communication link costs and available local storage and/or processing resources. Each appropriately configured network device acts as an active participant in network migration. In addition, portable two-dimensional (2-D) code reading terminals are configured to wirelessly communicate compressed 2-D images toward stationary access servers that identify the code image through decoding and through comparison with a database of images that have previously been decoded and stored.

대표청구항 ▼

We claim: 1. A communication network, comprising: a plurality of computing devices comprising a roaming terminal device, at least one computing device comprising a wireless transceiver; and a plurality of access devices supporting wireless communication among the plurality of computing devices, the

We claim: 1. A communication network, comprising: a plurality of computing devices comprising a roaming terminal device, at least one computing device comprising a wireless transceiver; and a plurality of access devices supporting wireless communication among the plurality of computing devices, the plurality of access devices comprising a first access device and an access device downstream with respect to the first access device, the downstream access device retaining a particular program code or a particular data, wherein the first access device sends a request for the particular program code or the particular data to the downstream access device, and wherein the first access device determines whether to request a migration of the requested program code or the requested data from the downstream access device to the first access device. 2. The communication network according to claim 1, wherein a copy of the requested program code or the requested data migrates to the first access device. 3. The communication network according to claim 2, wherein the copy migrating to the first access device is stored in the first access device. 4. The communication network according to claim 1, wherein a copy of the requested program code or the requested data migrates upstream to be accessed by the first access device or by a device upstream of the first access device. 5. The communication network according to claim 1, wherein the plurality of access devices comprises a plurality of access servers, and wherein the plurality of access servers support local processing and provide program code migration and data migration. 6. The communication network according to claim 1, wherein the plurality of access devices support remote processing. 7. The communication network according to claim 1, wherein the plurality of access devices support program code migration, data migration and local processing migration. 8. The communication network according to claim 1, wherein the first access device and the downstream access device support local processing and provide program code migration and data migration. 9. The communication network according to claim 1, wherein the communication network uses a spanning tree protocol to provide network coverage. 10. The communication network according to claim 1, wherein the particular program code comprises a program object. 11. The communication network according to claim 1, wherein the particular data comprises a data object. 12. The communication network according to claim 1, wherein an initial program code request or an initial data request does not identify a particular access device or a particular computing device on which the requested program code or the requested data is retained. 13. The communication network according to claim 1, wherein an initial program code request or an initial data request is forwarded in accordance with a spanning tree algorithm. 14. The communication network according to claim 1, wherein the roaming terminal device initially accesses the at least one of the particular program code and the particular data via the first access device and the downstream access device, and wherein the first access device forwards the at least one of the particular program code and the particular data from the second access device to the roaming terminal device. 15. The communication network according to claim 14, wherein, after at least one of the particular program code and the particular data has migrated to the first access device, the roaming terminal device accesses the particular program code or the particular data via the migrated program code or the migrated data stored in the first access device. 16. A communication network, comprising: a plurality of computing devices comprising a mobile communication device, the mobile communication device comprising a wireless transceiver and supporting requests for program code and data; and a plurality of access devices supporting wireless communication among the plurality of computing devices, the plurality of access devices comprising a first access device and a second access device, the second access device being downstream of the first access device with respect to the mobile communication device, the second access device storing a particular program code or a particular data, wherein the mobile communication device generates a request for the particular program code or the particular data and transmits the request to the second access device via the first access device, wherein the second access device forwards, via the first access device, the requested program code or the requested data code to the mobile communication device, and wherein the first access device determines whether to migrate the requested program code or the requested data from the second access device to the first access device based on one or more migration factors. 17. The communication network according to claim 16, wherein the mobile communication device comprises a roaming computing terminal. 18. The communication network according to claim 16, wherein the request does not identify the second access device. 19. The communication network according to claim 16, wherein the request is forwarded throughout the plurality of access devices in accordance with a spanning tree algorithm until a particular access device retaining the requested program code or the requested data is identified. 20. The communication network according to claim 16, wherein the one or more migration factors comprise at least one of a count of the number of times that the particular program code or the particular data is requested, a duration of time over which the count is taken, a cost of retrieving the requested program code or the requested data from a downstream source, a size of the requested program code or the requested data, and remaining local storage capacity. 21. The communication network according to claim 16, wherein the mobile communication device supports requests for remote local processing. 22. The communication network according to claim 16, wherein the plurality of access devices support remote local processing.