These four key values shape everything we do. We believe in building strong relationships, empowering careers and business growth. Let's start the conversation today. That level of care and providing instant value is exactly what you want. That's what we want to do in this business, and that's what Client Server do from a technology recruitment point of view. I feel very positive about Client Server. Amanda Cavallaro - Software Developer, Gamesys. We work with candidates from all over the world and have a detailed understanding of the technology jobs market.
Can someone please explain what "cloud computing" means in contrast to client-server? As far as I understand it, cloud computing is more of a network services model, such that I do not own or maintain the physical hardware.
The "cloud" is all the back-end stuff. But I still might have an application that communicates with that "cloud" environment.
And if I run a web site presents a form that a user fills out, pushes a button on the page, and returns some report that was generated by the web server, isn't that the same as "cloud" computing? And would you not consider my web browser as the "client"? Please note my question is specific to the concept of "cloud computing" with respect to "client-server". Sorry if this is an inappropriate question for this site; it's the one closest in the Stack universe and this is my first time here.
I'm an old timer, programming since mainframe days in the late 70's. Strictly speaking, there is no 'Cloud'. Not in the sense of what that CEO was spouting. There's an Internet, of course.
There's hosted services. There's VPS's. There's content delivery systems. We've technical folks have adapted to the term to reference certain hosted service models. But 'Cloud' in consumer media is largely a marketing term loosely translated as 'internet'. More often than not, it also means 'I get to charge you by the month'. You are correct in your thoughts that the two terms, 'cloud' and 'client-server' aren't related.
Having a service hosted 'in the cloud' I always want to add a dramatic 'dun-dun-daaaaaaa' after using that phrase does not make a client-server app any less client-server-y. For example, the 'web' primarily uses a client-server model. The web browser is the client. The web server is the server. So the term client-server defines the relationship between two entities in a system.
Where the entities are physically hosted is irrelevant. In a traditional client-server model, which is definitely still in common use today, a client connects to a server that performs a particular job.
This server may host a database, or a series of file shares, or a webpage. When the client connects to that server, there is an implicit understanding of the type of communication and data transmission that will ensue between the two computers. There may also be an understanding by the client, or the end user, of the capabilities of the server's hardware, and its limitations.
This relatively "tight coupling" between the client machine and its server can pose problems for a sysadmin who needs to take down a server for maintenance; all the applications dependent upon resources provided by this server have to be pointed at another server, and not all applications and infrastructures are designed with this type of redundancy and failover-tolerance in mind.
In a cloud model, the hardware, topology, division of labor, and even number of actual machines involved is all abstracted behind a single endpoint. The analogy could be drawn to a modern "web application", as opposed to older generations of "website" which were more static.
We might guess that there is an application server and a DB server behind the scenes, but we really don't have to care; the web server, as part of its job to serve the full application to users beyond the "edge", provides a unified endpoint allowing controlled access to all the data and services provided by other machines behind this front door.
The upshot is that, with a single endpoint exposed to provide the functionality of the application, that's all a client consumer of the application ever has to care about, instead of where to get its data, where to call such and such a remote application process, etc; that means that the administrators and architects of the service provider within this cloud are more or less free to change the machines, topology and other specific implementation details of this "cloud service" without the clients being any the wiser.
Facebook could, if it thought it wise, rebuild its entire data storage system from scratch using a different DBMS and all new servers, and as long as the site remained available during the transition, nobody would ever be the wiser; in fact, Facebook did just that, many times, as it expanded from a site hosted from Mark Zuckerberg's personal machine in a dorm room to dedicated hosting off-campus, to server farms in several locations worldwide.
In "classic" deployments one ordered a specific machine for a specific application and did quite fixed configuration. In a cloud environment there is more or less standardized hardware in a pool and an API which creates and configures virtual machines on it from some form of templates. By that faulty systems can easily be replaced, scaled up or scaled down depending on needs and the hardware be allocated as needed, een in an automated way.
Of course proper admins did most of that before, too, but besides pure marketing, there is a foundation of standardized APIs Aamzons AWS API which is also offered by tools like Eucalyptus for "private clouds" and tools i.
In 'traditional' client-server architecture you had statically assigned resources or at least it is presented as such - I don't have experience from pre-cloud period so please correct me if I'm wrong and depend on false marketing. The database server was called db. If you wanted to increase resources you might add another dedicated webserver and provide load-balancing etc.
On the other hand in cloud stress have been put on abstraction of lower levels and denote how the 'server' is constructed. On the For example you have:. The communication throughout the process was perfectly pitched and I'm very happy with the end result.
They provide a very professional approach, excellent communication and an overall exceptional service in recruitment David represents those values extremely well I had no questions unanswered. He has organised the process with flawless precision. I would always recommend him.
0コメント