SELECTION OF CAPILLARY NETWORK GATEWAY TO A CELLULAR NETWORK

摘要

The present disclosure relates to capillary network gateway, CGW 12a, 12b, selection in a capillary network. In particular, the present disclosure relates to methods and arrangements for linking a machine device, MD 11, operating according to a local area radio access technology, RAT, in a capillary network, to a cellular network via a CGW 12a, 12b, wherein the capillary network comprises a plurality of CGWs that each have a connection to the cellular network. A plurality of MDs 11 is connected via a local area radio access technology, RAT, of the capillary network to the CGWs 12a, 12b which in turn are connected to respective radio base stations, RBSs, 21a, 21b of the cellular network. An MD 11 may be capable of setting up a link to the cellular network by means of multiple CGWs and thus a selection of CGW should be performed prior to establishing the link. A method for selecting the CGW comprises determining one or more dynamic properties for each of at least two CGWs of the plurality of CGWs, wherein the one or more dynamic properties relate to a traffic processing and forwarding capability of the respective CGW, and controlling selection of at least one CGW out of the at least two CGWs based on the determined one or more dynamic properties. The step of determining preferably comprises determining the traffic load experienced by the CGW, the channel quality of the CGW's connection to the cellular network and/or the radio access technology for the CGW's connection to the cellular network. The MD may be instructed to set up a local area radio connection to a CGW by means of an RPL message (Routing Protocol for Low-Power and Lossy Networks), a link layer message, a CoAP message (Constrained Application Protocol) or an OMA-LWM2M message (Open Mobile Alliance Lightweight Machine-to-Machine), or a broadcast or unicast Ipv6 router advertisement.