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Default solution: SaaS

While it's since a couple of year the prefered way for big companies to offer services like that, mainly for commercial reasons, in our case offering Flying Fleet as a SaaS model offer multiple advantages:

Easy to update and keep up to date the system

Using a central management system, Redcrest GmbH can deploy as frequently as needed updates and maintain the servers up to date. Base infrastructure is rented at a EU company and hardware infrastructure is kept in the EU zone. This ensure that in case of hardware failure the IT provider is responsible to keep the system running, and Redcrest GmbH is only responsible to maintain the OS and Software up to date. With about code 1000 commit per year, maintaining a cloud infrastructure is actually more affordable and easy to supervise.

Online access for external users

For multiple scenario, like PPR or aircraft reservations, users must be able to access the system from Internet. Having the servers already on a public cloud solution allows fast and reliable access.

Distributed backup

Backups are copied on different data-center in the catastrophic event of a data-center disaster.

Architecture

Redcrest Solutions GmbH is responsible to rent a VPS per customer in an EU data-center. OS and software installation will be performed for the customer. Only access to the application and the backups is available to the customer, no access to the server directly.

On Premise

Data privacy and reduced Internet dependencies may push to choose this solution, however Redcrest GmbH cannot maintain a server infrastructure for its customers, therefore a local partner must be found which will be responsible of the hardware maintenance.

Costs

Cost reductions are minimal if any in the long run, while an higher initial cost is required at the start as well as a renewal plan (about every 4 years) must be planned. On call costs for the local hardware provider may need to be in budget as well.

Online access for external users

Either completely impossible or will require a more complex setup such that external Internet access is possible via a firewall or equivalent.

Risks

In case of an hardware failure, the time to find an hardware replacement and the setup time may mean days of down time (depending on the local support).

Architecture

The software is installed by Redcrest Solutions GmbH on a Linux X86 server or PC. It must be possible to have a remote access (SSH) to the server. Daily the server will check for new software updates and will automatically install the updates. Data is all local and a backup can be setup to copied to a remote location. Hardware and OS related issues are under the customer responsibility.

Advantages

Not relying on a possibly unstable Internet connection, and depending on the hardware chosen, higher performances.

Drawbacks

Higher risks of infrastructure issues.

Hybrid solution

Mixing both previous solutions, an hybrid solution can be proposed, where the primary access is done via the cloud solution and a local hot standby server may be used in case of Internet blackout.

Architecture

A VPS as well as a server / PC are setup. The DB will be mirrored (in real time) having the master installed on the VPS and using the local computer as slave. In case of Internet downtime, a script can be run to switch the hot standby as active system. Later on a backup of the hot standby can be imported on the VPS. The data replication is based on the MariaDB database replication.

Costs

Due to the requirements of both previous solution, this is actually the most cost intensive solution while offering nearly the advantages of both worlds.

Risks

Allowing data replication over Internet may introduce a small security risk (which can be mitigated using VPN connections or other solutions). Data changed on the cloud instance while the local computer is used as master instance will be lost when the switch back is done.