In the Old Days
In the old days – though even as recently as a decade ago – there were two distinct types of network infrastructure in the corporate world: private networks, and those that used the public internet. A private network was, by default, a secure network. A company would build out their network infrastructure using MPLS, and traffic would never touch anything other than their private, secure network.
Companies using the public internet had a more difficult time dealing with security because their data traveled over lines that anyone could attack. In order to keep data secure on the public internet, businesses would use IPsec encryption which is secure enough for most uses, but is more prone to latency issues and certain types of cyber attack.
Both of these approaches had advantages and disadvantages, of course. Private networks are great for latency-sensitive apps like video conferencing thanks to class-of-service prioritization, and they are protected from DDoS and similar attacks. A private network is much more expensive to provision than an IPsec-based network, though, and most businesses don’t really need the low-latency performance of a private network.
These Days
Partly thanks to the huge increases in available network bandwidth over the public internet, and partly in response to customer demand for more immediate and personalized services across all sectors, businesses have been changing the way they structure themselves. Where years ago a business might maintain a main office and very few satellite sites, these days the ratio has reversed. In a modern business context, it is common for smaller branches to outnumber main offices, often by orders of magnitude.
This is possible because cloud computing solutions have blurred the lines between private and public networks in the modern context. Companies are increasingly moving their workloads into the cloud. They are also increasingly satisfying their need for a secure network through a combination of public and private network infrastructure – MPLS based networking between critical sites such as head offices, and IPsec encrypted connections between branch locations and mobile employees.
Newer technologies such as software-defined networking and the ability to virtualize most network functions mean businesses can adapt their network topology on the fly as needs change. This allows for a much more agile and flexible response to both business needs and security threats, making a hybrid cloud-based network one of the more secure network options available. It doesn’t hurt that cloud solutions are generally much more cost effective as well.