The client-server model is, today, one of the main components of network computing. Initially, it distinguished PCs’ computing from the mainframes’ centralised computing model.
Many things have changed throughout the years, from the network nature to how traffic travels within one. These changes also happened thanks to the client-server model. But what is it exactly?
What does the client-server model entail?
As the name suggests, the client-server model entails a relationship between the client program and the server. In particular, the client requests a specific service or resource from the server.
The two elements communicate through a LAN or WAN connection, like the internet. When it comes to the internet, specifically, the majority of information used to move with north-south traffic, meaning that data is exchanged between remote clients and data centres. Today, on the other hand, information assumes an east-west traffic pattern, meaning that communication happens between a server and another server.
After the client sends the request through to the server, and the server completes the task, their communication ends.
What are the advantages and disadvantages of the client-server model?
Like every procedure, the client-server model also has both disadvantages and advantages.
When it comes to the latter, such structure is convenient for various reasons, such as that all the data is concentrated in one single place – the server – which augments the security and makes authentication easier. In addition, the server and client do not need to be physically close in order to complete the transaction. They can also be on two different operating systems since the data moves through platform-agnostic client-server procedures.
However, the model has faults too. For instance, if too many clients request data at the same time, the server risks becoming overloaded, which ultimately can end up in a denial of service. If this happens, no request will be able to be fulfilled. In addition, the setting up and maintenance of a client-server model are expensive.
What is the difference between a client-server and a peer-to-peer model?
The peer-to-peer (P2P) network is another type of program relationship model. There are several major differences between P2P and client-server, such as the fact that while the latter sees two differentiated entities (the client and the server), the former does not differentiate the two, since each node is both a client and a server simultaneously.
A P2P network is usually made of 12 or fewer machines, which share data with every other node. Since the components (nodes) both consume and produce resources and services, the higher their number the higher the network’s ability to share resources. Contrary to client-server models, the P2P cannot become overloaded. However, even if slightly more efficient, P2P’s nodes are at higher risk of a cyberattack since it is harder to maintain a high level of security.
In summary, P2P models are less stable than client-server ones.