I along with so many IT professionals hate the term “Cloud” because it tends to be used for everything under the sun anymore. I wanted to take this post to go into what cloud actually is and what types of cloud are out there. This is Cloud 101 first day syllabus stuff, and will be a part of a series on cloud technologies that I have been working on researching and testing. So let’s get into it and if anyone has any questions please let me know.
What is “Cloud”?
I will leave the first use of the actual word up to MIT’s Antonio Regalado who blogged about it here. But what is “cloud” in the context of a technology? Is it the concept of hosting your data in a public data center? Or is it the idea of having applications and data available from anywhere at anytime via mobile or traditional clients?
There are differences of opinion here because of the differences in types of cloud. Public, Private, Hybrid are the current topology defined categories. But with in Public cloud for example there is Single Site, Co-located, Shared Resource, and Dedicated Resource topology possibilities. The quick answer is Cloud is a combination of resources that provide resilient access to applications and data.
Public Cloud: Hosted computing resources in a data center that your organization doesn’t own or operate. Support options will be available for touch support or full managed for the servers and vm’s in the environment.
Single Site, Multi-Site, Co-Located: When researching Public Cloud providers or Hosted Solution Providers, make sure you determine if your cloud will be hosted at a single site or multiple sites or if it will be in a co-located data center. Single Site provides you with a just that a single data center that hosts your cloud, this may be all your organization needs, if the data center is capable of 5 9’s (99.999% uptime). But the reality is you will have redundant redundancy with multi-site providers. Some cloud providers are co-located or co-lo’s this means that they rent space in a larger hosting companies data center to get their multi-site redundancy. A co-lo tends to be a bigger data center with better pipes (bandwidth for incoming and outgoing connections) vs a single site instance that a smaller cloud provider may own. Then the question of SLA’s (Service Level Agreements) needs to be discussed, what guarantees are you getting from the Cloud provider that your data will be available and secure? A good cloud provider will offer credits back for any downtime outside of that expressed in the SLA’s as maintenance.
Pros:
- Public Cloud gets the IT budget burden of hardware and virtual platform licenses out of your organizations budget
- Can reduce the cost of Application delivery and overall OPEX
Cons:
- Security this isn’t really a negative it is just like any other IT initiative if you properly plan your security and implement smart policies you can achieve a secure cloud environment
- CAPEX initial migration can seem like a large investment ROI needs to be examined and OPEX should be included in that analysis
- Change Management is needed more than in a private environment to ensure that your organization didn’t impact the SLA’s and to ensure that your provider is living up to their end of the agreement
- IT Department push back this is the biggest issue the fix is to help the IT team understand the goal and direction of the organization and how cloud plays into that
Private Cloud: Your organization utilizes its internal IT resources to provide access to applications and data. Typically this is a multi-site approach with secondary data centers or branch offices being used for redundancy.
Pros:
- CAPEX investments have already been made in most situations with fewer dollars a cloud vision can be realized
- Ownership the organization owns the hardware and software that is implemented in the cloud, this means that it can be depreciated and written off over time as well
- The other piece of ownership is that the organization has direct control over the assets and personnel who work in your environment this is the old adage of an enemy with-in can wreak more damage than an enemy at the gate. Knowing the staff in your IT environment is a valuable security measure.
Cons:
Hybrid Cloud: Is exactly what it sounds like, your organization maintains both a public and private cloud presence and there are applications in both locations. This allows for secure data to be maintained in the private cloud and public data to be provided in the public cloud. Data and Applications can easily maneuver between the two environments.
- CAPEX & OPEX the organization is still paying for the IT personnel and resources as well as power and cooling for the data center
- Cost of application licenses that are sometimes included in public cloud offerings.
Hybrid Cloud: Is exactly what it sounds like, your organization maintains both a public and private cloud presence and there are applications in both locations. This allows for secure data to be maintained in the private cloud and public data to be provided in the public cloud. Data and Applications can easily maneuver between the two environments.
Pros:
- Best of both worlds, managed environments with lower CAPEX
- Maneuverability and redundancy for critical environment applications
- Lower OPEXCAPEX for fail-over site than dual on-premises or dual public cloud solutions
Cons:
- Cost essentially this boils down to having your cake and eating it too. Your organization has the costs of both on premises and a public cloud hosting site.
