The advantages and savings of OFFLINE mode in mobile applications also known as "partially disconnected" mode

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Do your mobile employees find it difficult to work and scan with a permanent connection that is interrupted or too slow? Do they lose captured data if the connection is interrupted?

The offline mode of the applications allows you to work quickly with a lot of data with intermittent networks, i.e. with network at the start and at the end of the mission to exchange data with the servers and no network during the data entry mission.
This offline mode also saves network operators’ mobile data subscriptions if "real time" is not required, or expensive wifi installations inside industrial buildings.

With this mode, maximum use is made of the functions and power of terminals and smartphones and few networks.

Connectivity is much more than just coverage and is not sufficient for high speeds or multiple fast accesses. It means being able to carry out your tasks anywhere and anytime, and it requires software capabilities in the terminals.
And this is exactly what Productivix with its specific mobile applications can help you accomplish.

Here we explain the definitions, the savings for the customer, the terminal structure of our developed mobile applications, its offline input/output working mode with a database server and the advantages for the user and customer.

One can be "online" in the classical way == "online" and also in a so-called "offline" mode,

Online and Offline mode definitions Online and Offline mode definitions.
Online / on-line = synchronous, requires to remain permanently connected to the network and data server and to the application which is no other than a web application on the server as well. Without a connection, or with the slightest interruption, immediate data is lost and the input process is interrupted. The terminal is used as a simple screen, its memory and processor are almost unused.

Offline/off-line = asynchronous, another term used is "loading / unloading data". Mode of the application which collects on the server data necessary for a mission in the near future and which depends on a work context; mode which then collects and stores locally on the mobile machine the data collected by the user, then when the network is present, returns it completed to the server by taking over other basic data for the next "mission".

Example of savings made by a PMI on its Wifi infrastructure produced by offline mobile applications

The company studied is in mechanics and has inventories in a remote room, filled with metal that screens out radio waves (metal shelves, large metal parts, frames and cladding).

It wants to carry out stock removals and inventories, entries with a mobile hardened terminal (bar code).

The classic publisher offers her mobile terminals with the installation clause of a total coverage of her stock in Wifi. Access to the application is via the terminal’s web browser, therefore synchronous: the application responds as long as there is network coverage. The quantity of metal means that the number of antennas and the power to be installed must be large to cover the area. The slightest network failure in a corner, for example, prevents the correct capture.

With our offline solutions, we can avoid covering the whole stock but only place a single wifi hot-spot located on an important point of passage, such as access to the coffee machine or changing rooms. This point will allow us to return to synchronise and upload the data entered and work without a network most of the time.

Example of faster data entry on an offline picking chain

The customer put in 5 barcode terminals for intensive order picking. There were multiple database accesses per entry: the first version was online: the wifi link did not keep up with the pace and the application’s response time was heavily impacted by network conflicts at the wifi point: operators were very often waiting for the application. The solution was to develop an application in offline mode, the maximum speed was that of the operators and not that of the application.

Example of data subscription savings for a carrier on 10 terminals for entering parcel receipts with the offline mode

The courier has parcels to be deposited by recording the GPS positions and possibly the customer’s signature. He needs the data the next day only. The offline mode of data transfer as soon as a Wifi terminal (home, office, bar, restaurant, hotel) is authorised is enough for him: he has saved 10 mobile data subscriptions.

Structure, Android smartphone architecture, barcode or Rfid terminal and impact on offline mode

In order to better understand the advantages of the Offline mode, it is necessary to explain the technique a little more.

A barcode terminal (or Rfid) has at least the following hardware, inherited from the smartphone in passing:

  • a microprocessor and its operating system (currently mainly Android) to run the programs designed for it.
  • volatile memory to work with,
  • permanent memory for battery-free storage of data tables between work sessions,
  • of a battery,
  • a screen, usually a touch screen,
  • the Wifi network,
  • of a scanner, whether barcode (1D or 2D, or Rfid or both) which allows faster and error-free data entry : ->art390],
  • optional :
    • a physical keyboard (real keys)
    • a USB connection,
    • a 3/4G data and telephone network system,
    • sensors: NFC, temperature, GPS, gyroscope, etc...

The terminal’s operating system has a feature that will mainly interest us: a lightweight, embedded database management system called SQLite which is SQL compatible. The application can therefore make queries on its local data as on a server, but without the permanent network.

How does the Offline mode work? also says: disconnected mode, offline

For example, we want the user to have the designation of the scanned item displayed.
In this case, we need the article table with the scanned code and its designation in the terminal, and then we need data to be loaded from a zone with wifi or 4G network into the terminal, which has the ability to store this partial image from the server database, here in our example the article table.

Mode offline : les données sont stockées sur le terminal
Le terminal mobile est de temps en temps connecté au réseau et à ses bases et échange des données en entrées comme en sortie pour travailler en autonomie.

Once this data has been loaded, the user and his terminal will be able to go on a field trip and work with the included application, without needing the network, if there is one (imagine that this happens underground or in high mountains).

If the scans and data entries are fast and interrogate the database on board the terminal, we do not depend on the network but on the local power of the portable terminal.

Let’s imagine that it is an application for registering fire extinguishers that are part of the on-board items and that we need to add data such as the GPS position, the date and time of their visual observation. These censuses are therefore entered in another table (let’s say "Census").

La synchronisation offline permet un travail avec un réseau wifi de couverture légère
Nos terminaux avec nos applications ont une petite copie des données de l’ERP nécessaires au travail en absence de réseau

If the scans and data entries are fast and interrogate the onboard base on the terminal, it does not depend on the network but on the local power of the handheld terminal.

In the meantime, the article table on the server has been completed with another new article by another user.

Once the tour is over, the user returns to the area with network (Wifi or Ethernet cable dump well) and restarts a synchronisation.

The Census table of the terminal is emptied into that of the server and the item table of the terminal is completed with the new item.

Mode online : synchronisation des données
Un mode offline (déconnecté) commence et fini toujours par un mode online (connecté) pour synchroniser les données, mais de manière rapide et limité

These rules for synchronising the start and finish are of course programmed.

Transfers in offline mode on the network are only modified data, therefore little, and in online mode, the exchanges are those of the appearance of the application (screen) plus all the data: therefore 10 to 50 times more. The offline mode is network-saving (at the time of considering 5G...).

The advantages and disadvantages of the Offline mode over the Online mode

Once the offline mode has been understood, it is of course possible to list the needs and usage characteristics of these applications and their advantages.

Features Online / synchronous mode Offline / asynchronous mode
Speed of queries and entries Network and server dependent Local and fast, network independent
Data Add-On Impossible without network Possible without network
Mobile network subscription fees (3 or 4G) Yes No or not imperative (*) if no emergency
Big databases Slow queries Slow queries with the parts of the base useful for the mission and fast local queries
If weak or saturated wifi connection does very poorly functioning very well
Server power used server power terminal processor power
Required network coverage rate 100% 1 to 5% (just crossing points)
development the publisher did it or not (PC mode in smaller size) by us
ERP Licences uses editor licences per terminal saves editor licences per terminal and allows other applications independent of the ERP to be made on its terminal

It is clear that the offline mode, undoubtedly more complex to program, responds more to tough field situations, but also produces immediate savings.

(*) if you have an intermittent and irregular network, it is possible to set in the application to synchronise as soon as the network is present after a defined number of minutes. In this way the demand for spontaneity of 98% of the applications is met with a speed of input and work for the operator.

Of course, the majority of our KX-mobile standard traceability mobile applications and customised Std & customized mobile production or delivery traceability apps "KX-mobile" are realised in offline mode.
Ask us for advice!