9 May 2023

Building resilient connectivity: The case for redundancy

Building connectivity reliability

The rise of cloud and SaaS technologies has made reliable connectivity essential. Outages and slow connections are not just annoying but can also have serious consequences for enterprises. This is why, in the digital age, building redundant infrastructure is the key to protecting a company's IT infrastructure and ensuring business continuity.

Redundancy creates resilience

Redundancy creates resilience by protecting against incidents that paralyze parts of the Internet infrastructure. The concept of redundancy means that there should always be at least two paths leading to a destination. In a communications network, two locations should be physically connected via multiple independent cables. This means that in the event of an incident, the traffic of the failed line is redirected via the other transmission paths.

The system should be operated in an active/active mode by default. This means that all available lines are always partially utilized, and, in the event of an incident, the traffic of the failed line is redirected via the other transmission paths. This has advantages over an active/passive mode, where it is not automatically guaranteed that the alternative cable will work completely reliably at the required moment.

Keep the “last mile” in mind

However, redundancy is not automatic. While redundancy through geo-diverse data pathways is the standard between data centers and Internet Exchanges, this does not apply to what is known as the "last mile," such as DSL connections to end-users. Instead, users and organizations need to ensure that there is a connection to a higher level of the network via a second redundant line. In the private sector or in small businesses, this can be achieved for example via 5G-capable routers.

Larger companies should ensure that they are connected to the Internet via multiple, high-performance geo-diverse lines. A resilient infrastructure must be planned, built, and regularly tested in cooperation with one or more providers. Companies that connect directly to an Internet Exchange (IX) should also pay attention to redundant connectivity and establish multiple redundant, geo-diverse connections between themselves and the IX.

The loss of an Internet connection is comparable to a power outage for many companies. Companies that want to be on the safe side for their business activities should treat the topic of redundancy as a top priority.