The 5 best methods of data transmission


Are you looking for the best way to lease and transfer data for a public institution or your business? Wondering whether to lease the port on the switch or opt for more advanced solutions? We have a complete guide for you. Find out what devices you'll need, what the potential costs are, and how to choose the option that gives you the most flexibility and control.  

In the article “If not copper, then what?” we have already discussed the basics of fiber and copper technology, the main differences between them and the concept of wave multiplication. Now we will move on to the practical aspect: how to use these technologies in the construction of your own infrastructure or in the context of the services available from the operators.

Port on the switch

One of the most popular methods of data transfer is the lease of transmission services from the operator. And that is exactly what we would like to focus on. Let's start with one of the simplest, most common and effective ways: port lease on the switch. In this context, we use the term “switch” in a general way and understand it as various devices of higher layers, such as switches or routers of the third layer, for example.

What does it look like in practice? We go to our supplier with a request to lease the port on the switch. When we decide to lease, for example, a 10 Gb Ethernet port on a switch, we get guaranteed speed and access to the port on the operator's device. We can then connect our own copper cable and enjoy stable data transmission. The approximate cost of such a service is about 3500 PLN (per 10G port), which makes it attractive for many users.

When choosing to lease a port on a switch, however, we are faced with some limitations. We are tied to a single, specific speed, for example 10 Gbps, and to a single protocol, in this case Ethernet. If we wanted to use Fibre Channel transmission, we would have to ask the provider for an additional port that supports this protocol. In addition, in the event that the available bandwidth is exhausted and the need to add another transmission of the same speed, it will be necessary to lease another port. That is, the costs increase in a linear way: the more different transmissions we plan to launch, the more ports we have to lease.

Port on muxsponder (Alien OTN)

There is also an alternative known as “Alien OTN”. Like leasing a port on a switch, it doesn't require you to have your own fiber optic infrastructure or specialized network building experience. The difference is that we do not rent a port on a third or second layer device only on a muksponder, that is, on a device that supports the OTN (Optical Transport Network) protocol.

As in the previous case, we get a bandwidth allocation that we can use for data transmission. OTN technology operates below the second layer of the ISO/OSI model, acting as an intermediary between the physical layer and the data link layer. OTN uses special OTU frames, with different bandwidth levels, from OTU0 with 1.25 Gbps, through, OTU1 — 2.5 Gbps, OTU2 — 10 Gbps, OTU3 with 40 Gbps, up to OTU4, which achieves a bandwidth of 100 Gbps.

In short, OTN allows the aggregation of various services in a single transmission “container”. For example, in an OTU2 frame, which has a bandwidth of about 10.7 Gbps, we can place one transmission of 10 Gb Ethernet, but we can instead also run for example, 10 transmissions of 1 Gb Ethernet. Of course, we do not have to use the full 10G or 100G band on the first day, we can expand our system as the demand for transmissions increases.

One of the main advantages of Optical Transport Network (OTN) technology is that we are not tied to a specific protocol, but to a bandwidth band. Take for example the OTU4 frame, which has 100G data fields and a total bandwidth of 112 Gbps, to this frame we can aggregate different services such as 10 Gb Ethernet, 16 G Fiber Channel or STM transmissions, with the only limitation: no redundancy. Everything is copied 1:1, so we cannot exceed the 100G band.

Port on the multiplexer (Alien Lambda)

What if we need a service that offers complete freedom in terms of bandwidth? We need to go a level lower and instead of plugging into the operator's active devices, such as switches or muksponders that support OTU frames, we connect directly to the passive optical multiplexer. In this case, the bandwidth is not limited by the port, which means that we can broadcast with any bandwidth, from 10G to up to 400G if needed.

In summary, “Alien Lambda” gives us the most versatile approach to leasing from the operator, without limiting us either by bit rate or by the types of services we can aggregate. We have our own transmission channel for data transmission.

As for the cost, “Alien OTN” type services for the OTU4 frame oscillate in the range of PLN 5,000 - PLN 6,000. This is about twice the cost of a single port on the switch, but with much greater capabilities. When it comes to a single channel on a multiplexer, the cost drops, giving us even more possibilities.

Data transmission equipment

Now let's figure out what infrastructure and what devices are needed to use OTN technology? When we are dealing with Ethernet, all we need is a standard Ethernet switch.

In the case of Alien Lambdy and Alien OTN, the situation is somewhat different. We need special devices such as transponders and muxponders.

Muxponder is a device that offers high bandwidth on a line port, for example 10 Gb, 100 Gb, 200 Gb or even 400 Gb. On the client side, we can aggregate lower bandwidth services such as 10Gb Ethernet, 16Gb Fiber Channel, etc. In a sense, this can be compared to a layer one switch, with the difference that we use an OTU frame and not an Ethernet protocol.

The main limitation is the bandwidth of the line port. For example, if our line port has a bandwidth of 400 Gbps, then we can run services with a total speed of 400 G. Of course, these services can use different protocols, such as Fiber Channel or Ethernet and different bandwidths, from 10 Gb to 100 Gb.

It is also worth noting that we do not need to immediately use the full capabilities of the device. We can start with a few services and gradually add more, since the configuration of new services is carried out continuously and does not affect the services already running.

Muxponder, as an active device, also gives us additional benefits. First, it serves as a demarcation point, which facilitates diagnosis in the event of a breakdown. We can easily identify if the problem is on the line side or in our server room. Secondly, muxponder allows us to encrypt the transmission for greater security.

Dark fibers or your own infrastructure

Let's also look at the possibility of building an infrastructure based on fiber optics, which will give us complete independence, without limiting port capacity or OTN frames.

The greatest opportunities are given to us by leasing dark fiber or having our own fiber optic infrastructure. We can use this fiber to connect different locations with optical modules or build a wave propagation system that will fully meet our needs.

Based on wave propagation technology, we can save on OPEX costs, we do not have to lease a large amount of fiber from the operator. All we need is one or a pair of fibers on which we will build the xWDM system. Depending on the built system, we can fully cover our transmission needs or build a system prepared for future expansion in terms of the number of services or their bandwidth.

In the case of renting dark fiber from operators, the cost is between 80 and 150 PLN per kilometer of fiber. The final price depends on many factors, such as location or the amount of fibers needed. Thanks to technologies such as CWDM, we can achieve significant savings.

However, the construction of such infrastructure requires specialized knowledge. When deciding on this solution, it is worth cooperating with an experienced partner. Salumanus specializes in the design and implementation of such systems, also offering post-implementation support. See more.


Data transmission management is a key element for any institution and company. Choosing the right path can affect efficiency, scalability, and operating costs. Whether it's leasing a port on a switch, using Optical Transport Network (OTN) technology, or building your own infrastructure on dark fibers, each option has its pros and cons.

There is no one-size-fits-all solution. The final choice depends on individual needs, capacity requirements and available financial resources. The Salumanus Advisor will help you understand the options available, their advantages, disadvantages and potential costs so that you can make an informed decision.

We will be happy to answer your questions. Email us:

Read more:

Why use xWDM in public institutions?

What is DWDM and why do you need it?

QSFP28 DWDM - Scalability Simplicity for DCI

Expanding networks from CWDM to DWDM

Muksponders: maximizing the use of the network