Fully in line with Industry 4.0

The IO-Link Com­mu­ni­ty has pub­lished a new spec­i­fi­ca­tion for easy data exchange. This spec­i­fi­ca­tion describes how data can be exchanged by IO-Link over JSON REST and MQTT – ful­ly in line with the trans­par­ent com­mu­ni­ca­tion of Indus­try 4.0.

The Indus­tri­al Inter­net of Things (IIoT) and Indus­try 4.0 are among the most impor­tant con­cepts and devel­op­ments for the future of indus­tri­al com­mu­ni­ca­tion. This future will require trans­par­ent com­mu­ni­ca­tion from the low­est sensor/actuator lev­el to a new gen­er­a­tion of mobile and cloud-based appli­ca­tions. One of the decid­ing fac­tors for this future will be sim­ple, stan­dard­ized and cross-man­u­fac­tur­er pro­to­cols. These pro­to­cols have to be able to work across all phys­i­cal lay­ers in order to enable glob­al access to data for iden­ti­fi­ca­tion, diag­nos­tic and con­fig­u­ra­tion infor­ma­tion. In the field of automa­tion tech­nol­o­gy, Eth­er­net-based com­mu­ni­ca­tion has been very wide­ly imple­ment­ed on the trans­port lay­er for some time now. Profinet is a glob­al mar­ket leader ahead of all the oth­ers here.

For seam­less data trans­port into the world of IT, JSON (Java Script Object Nota­tion) has estab­lished itself as a high­ly stream­lined exchange for­mat which can be used across all sys­tem bound­aries. Through addi­tion­al spec­i­fi­ca­tion of the seman­tics, easy inter­pre­ta­tion of the data is also made pos­si­ble. This enables the seam­less con­nec­tion of the IO-Link lev­el to MES/ERP sys­tems, cloud-based ser­vices and appli­ca­tions out­side clas­si­cal PLC automa­tion in general.

The demand for uni­form stan­dard­ized data con­sis­ten­cy from the low­est field lev­el to cloud-based ser­vices was accept­ed by the IO-Link Com­mu­ni­ty, which first defined a JSON-based exchange for­mat in a ded­i­cat­ed work­ing group and thus the uni­form seman­tic inte­gra­tion of the IO-Link field lev­el into the world of IT. The spec­i­fi­ca­tion encom­pass­es both the def­i­n­i­tion of an API as the REST inter­face and data trans­port over MQTT.

This stan­dard­ized exchange for­mat now pro­vides fun­da­men­tal­ly new oppor­tu­ni­ties, such as cross-man­u­fac­tur­er engi­neer­ing and glob­al access to mea­sure­ment val­ues and oth­er mon­i­tor­ing data. For exam­ple, clas­si­cal con­fig­u­ra­tion tools can be tied in across all man­u­fac­tur­ers by JSON via REST. Stream­lined “sen­sor to cloud” (IIoT) appli­ca­tions are also easy to imple­ment with the very wide­ly used MQTT pro­to­col with the publisher/subscribe mech­a­nism. This even makes it pos­si­ble to imple­ment a cloud-based automa­tion task with man­u­fac­tur­er-inde­pen­dent com­po­nents, for example.