How do I choose a Cloud hosting package?
Over the past few years, many Internet hosting companies have introduced cloud offerings. This new approach to hosting brings with it many advantages (flexibility, scalability...). But it also means that customers wishing to take the plunge will have to consider new constraints when choosing the solution best suited to their needs. Read all our advice on the challenges facing IT services.
The first part of this article lists the main criteria to be taken into account when choosing a Cloud hosting solution. The second part compares a selection of existing offers.
Criteria
- Private or public cloud? A public Cloud is one in which the infrastructure is shared with other customers of the Cloud hosting provider. In contrast, a private cloud consists of hosting the customer's services on a set of dedicated physical servers.
- Hosting company nationality. The country to which the company belongs, and the geographical location of the platform. This criterion can determine whether the hosting provider is subject to laws such as the U.S. Patriot Act. For the record: the Patriot Act authorizes American security services to access computer data held by individuals and companies, without prior authorization and without informing users. This access can take place on data stored at an American hosting company, even if it is a subsidiary located in a different country. Similarly, a subsidiary of a non-American company, but based on American soil, could potentially be required to provide access to its data.
- Technology. Type of virtualization used. Enables you to determine whether or not the hosting provider uses Open Source technology, and to obtain information on the level of partitioning of the system with respect to other systems on the same physical server.
- SLA (Service Level Agreement). Expressed as a percentage of time (e.g. 99.99%), this criterion corresponds to a contractual commitment by the hosting provider to service availability. A distinction must be made between network SLAs and infrastructure SLAs. The network SLA refers to interruptions in access to the infrastructure when it continues to operate, whereas the infrastructure SLA refers to a total interruption in service (due to a power failure, for example).
- Data redundancy. Guaranteed availability of stored data. Hosting providers generally provide information on the geographical sites to which data is replicated.
- Maximum resources per VM. Maximum characteristics available to a VM (number of processors, amount of RAM, disk space, etc.).
- Loadbalancing. The presence of a hardware or software solution enabling load balancing on several servers.
- E-mail and telephone support, on-call service. Is telephone support included in the offer? Is it available 24/7? Is a technician or engineer dedicated to each customer?
- Intervention and resolution guarantees. GTI (Guaranteed Intervention Time) and GTR (Guaranteed Resolution Time) included in the contract.
- Optional services. Various types of additional services: supervision, backup, facilities management, consulting, etc.
- Pricing. Billing options: by the month, by the hour, proportional to usage, etc.
Types of hosting
The diagram below shows that a Cloud offer should not only take into account the hardware infrastructure aspect from a financial point of view, but should consider ALL the services that are important for your Information System: supervision, security, backup, maintenance, evolution, on-call. These elements are part of your infrastructure environment and must not be neglected.
Specifications
This list of criteria is designed to help you draw up a set of specifications tailored to your needs. These specifications may include the following points:
- application criticality and expected availability
- system resources required (computing power, number of IOs, network bandwidth, etc.)
- cost/budget allocation
- confidentiality/sensitivity of hosted data
- planned short-, medium- and long-term development of the application
- expected support from the hosting provider
- supervision of hardware BUT ALSO of software (operating systems, system applications, business applications)
Comparison of existing offers
Here's a table showing a selection of existing offers and some of the criteria mentioned earlier in the article:
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Article translated from French