Optical network vs Ethernet

Defining optical and Ethernet networks

Optical networks

Optical networks send data as pulses of light through fibre optic cables. Unlike traditional networks based on copper cables, fibre supports much higher bandwidths and enables transmission over extremely long distances.

Optical networking also uses Wavelength Division Multiplexing, most commonly Dense Wavelength Division Multiplexing (DWDM). With DWDM, multiple data streams can travel simultaneously on different wavelengths over the same fibre, massively boosting capacity.

As a result, optical networking today underpins global digital infrastructure, from enterprise and metro links to backbone networks and data centre interconnects (DCI).

In this comparison, “optical networks” refers to high capacity, wavelength-based optical services such as Neos Networks Optical Wavelengths.

Ethernet

Ethernet is a wired networking technology that connects devices to networks for fast, reliable data transfer. Originally designed to connect local area networks (LANs) using copper cables, Ethernet has since evolved to support carrier-grade, high-bandwidth services over fibre.

Today, Ethernet is a vital element of business networks, from LANs to wide area and metro networks, linking offices, campuses and data centres.

In this comparison, Ethernet refers to managed Ethernet services, such as Neos Networks Business Ethernet.

Both optical and Ethernet services can provide high capacity connectivity. How do they differ, and which is the better fit for your business?

Optical networks vs Ethernet: key differences

Here’s a breakdown of how Optical Wavelengths differ from Business Ethernet services:

How scalable are optical and Ethernet networks?

Optical networks are highly scalable because DWDM lets you add multiple high capacity wavelengths on a single fibre. So it’s easy to boost capacity without installing new fibre. For example, Neos Networks Optical Wavelengths can operate at 10Gbps, 100Gbps or 400Gbps+. Adding or upgrading wavelengths at Layer 1 gives you substantial room to grow.

Ethernet is also easy to scale across LANs, WANs and metro networks, letting you increase capacity with demand. Neos Networks Business Ethernet services offer scalable bandwidth from 10Mbps to 100Gbps. Smaller bandwidth upgrades can often be delivered through configuration changes on the provider’s network. For larger upgrades, you may need new CPE if your existing hardware can’t support higher speeds.

In short, optical scaling is about adding or upgrading wavelengths at Layer 1; Ethernet scaling is about raising bandwidth within a managed Layer 2 service. Both scale well, but optical can reach far higher capacities.

Which delivers lower latency, optical or Ethernet services?

Optical wavelength services generally deliver lower latency than Ethernet on the same physical route. A wavelength follows a fixed end‑to‑end optical path, and optical components such as ROADMs and amplifiers add very little delay. So correctly engineered wavelength services can deliver very low, predictable latency.

In contrast, Carrier Ethernet crosses your provider’s switched Layer 2 network. Each switch hop introduces processing and queuing delay, especially under load. Even so, well‑engineered Carrier Ethernet can deliver consistently low latency over both metro and longer distance routes.

For both services, distance is the biggest factor impacting latency. Fibre propagation delay (the time it takes for a light signal to travel through fibre from A to B) is around 5 microseconds per kilometre, so that’s the physical lower limit.

If you need the lowest possible latency, a dedicated optical wavelength is usually the right choice. At Neos Networks, we configure services across our nationwide network with minimal hops to ensure low latency.

How reliable are optical and Ethernet networks?

Optical services are highly reliable for point‑to‑point, high capacity workloads because they use dedicated optical paths over fibre, which is immune to electromagnetic interference (EMI). DWDM line systems can be engineered with route diversity and optical protection. So a wavelength can fail over to an alternative path, maintaining predictable performance for mission‑critical use cases.

Ethernet services can also be highly reliable, depending on your provider’s end-to-end design. For example, Neos Networks Business Ethernet includes MPLS fast re-route and path protection on its core network. At the edge, you can add resilience and diversity options, such as Openreach’s RO2, which delivers dual Ethernet services on physically separate routes to eliminate single points of failure.

At lower speeds, Ethernet may be handed off over copper, which is more susceptible to EMI. But overall service reliability is determined by the provider’s core network and end-to-end resilience strategy.

For both optical and Ethernet services, good providers include stringent uptime and fault repair SLAs to keep you connected.

Are optical networks more secure than Ethernet?

Both optical and high capacity Ethernet services over fibre are highly secure when correctly configured. Fibre carries light, not electrical signals, so it’s harder to tap than traditional copper wires.

And both services provide robust traffic separation. Optical Wavelengths provide the highest isolation at the Physical Layer (Layer 1), giving you a dedicated wavelength – a private optical channel. Business Ethernet uses logical separation at Layer 2 with services such as EPL, EVPL and VPLS on a shared platform.

However, neither optical nor Ethernet services are completely immune to attacks. For sensitive traffic in regulated industries, adding end-to-end encryption is recommended for compliance.

How much do optical and Ethernet services cost?

Optical wavelength services are typically more expensive than Ethernet because you get a dedicated optical channel (wavelength) with fixed, high capacity bandwidth. Costs depend on the capacity (10/100/400Gbps+), circuit distance, and resilience and diversity requirements.

Business Ethernet is generally more cost-effective because it uses shared network infrastructure. Pricing varies by access type (fibre vs copper), bandwidth (10Mbps-100Gbps+), and resilience options such as RO2.

In short, consider optical services if you have specific bandwidth or latency requirements that justify the higher cost. Choose Ethernet for a balance of cost and performance for general enterprise applications such as WAN, SaaS and cloud access.

Ultimately, which is the better fit for your organisation depends on several factors.

Optical vs Ethernet service: which is right for your business?

Here are some key considerations to bear in mind when deciding between Optical Wavelengths or Business Ethernet connectivity:

1. Use case: What are you trying to connect: two high‑capacity sites, multiple sites, data centres or external networks via NNIs?
2. Capacity: Do your workloads need fixed 10/100/400Gbps+ bandwidth, or is flexible bandwidth up to 100Gbps enough?
3. Latency: Do you need the lowest possible latency on a specific route, for example, for real-time applications?
4. Distance: How far apart are your sites, and does the route length affect your latency or design requirements?
5. Scaling plans: How much capacity do you expect to need as your organisation and network demands evolve?
6. Cost constraints: For the network performance you require, do optical or Ethernet services better fit your budget?

Consider Optical Wavelengths if you:

Consider Business Ethernet if you:

Not sure which is right for you?

At Neos Networks, we offer a range of high capacity, low latency Optical Wavelength and Business Ethernet services across our UK-wide network. If you want to discuss the best options for your business, talk to one of our experts.