SDx in enterprise environments

Towards digital transformation

For a company that operates outside the telco sector, the corporate telecommunications network is not usually its business but simply a ‘utility’, necessary today, and that contributes to its viability. Through the digital transformation based on SDN, the aim pursued by any company is to improve the user´s experience of using the network, taking the business/employee/device as a reference.

Without losing sight of the benefits that SDN techniques bring, how can they add value to the company? Understanding what their business is and making its development possible, for which the network must try to optimize time, effort and complexity and get a better use of it.

Since the beginning of telecommunications networks, the main efforts have focused on the development of technologies, standards and equipment that make digitization possible, reaching companies of any scope and size. From network engineer’s point of view, this has resulted in the implementation of corporate networks focused on connectivity, networks designed to guarantee the availability of a location, a network element or access lines. As years go by, and as digitization has advanced, the communications infrastructure has become necessary and, due to the increase in its use, the focus has shifted from reliability / availability to optimizing performance and increasing bandwidths.

Nowadays, we could say that the basic needs that a company needs from a telecommunications network are covered, that is, connectivity. But new use cases are emerging, which makes them consider the evolution of the Enterprise network, without discontinuing the traditional lines of work of robustness and performance, following the guidelines of software-defined networks, through the implementation of network services of a homogeneous or deterministic, agile and scalable way.

In an Enterprise environment, three parts of the network infrastructure are mainly identified: Datacenter, WAN and LAN. In other words, shared resources (datacenter), connectivity between sites and from a site with shared services and, finally, connection of users or devices to the network and access to shared services.

Taking a company head office as a reference, we will try to analyze SDN solutions for WAN and LAN connectivity. On the WAN side, SDN solutions try to make better use of connectivity resources by focusing on business applications, measuring, and securing access lines. For its part, as far as the LAN is concerned, it focuses on the control of access and use of the network based on the identity of the employee or the device.

• Where are the WAN networks heading? towards the indistinct use of private and public lines (internet), migration of services and infrastructure to public or private cloud, consumption of Cloud applications … They are heading towards making the network more flexible and securing it, this being a private/public hybrid network.
• Where are the LAN networks headed? to work from anywhere (teleworking), from any device or machine (IoT). They are heading towards making the workspace more flexible and securing it.

Based on the above, cloud and mobility appear to be key factors that motivate SDN in Enterprise networks.

Flexibility is not easy, as it implies considering more options, and the more options, the more complexity and information (what happens on the network and how the network is used). Flexibility implies new security needs, with security being one of the main concerns of organizations today. Achieving a level of security and a uniform operational level for the organization, regardless of the connection mode or location, becomes important.

With great success, SDN solutions in an Enterprise environment have been able to hide the growing complexity of corporate networks to offer a centralized management or orchestration layer, aimed at simplifying network operations and deployment.

With the following steps we will try to address, in a simplified way, how to embark on the way to digital transformation in Enterprise WAN / LAN networks, based on SDN technologies. As a guide on this way, three questions will be addressed: the selection of a solution, its implementation mode and, finally, other important considerations from the perspective of three types of companies (multinational, big company, and SME).

 

Solutions catalogue

When we talk about SDN on the WAN and on the LAN we are not talking about a specific protocol or technology, nor are we talking about protocols, concepts or technologies unknown to network engineers. These are connectivity and security solutions created by combining a set of protocols and functionalities. It is this combination that provides complexity and a large amount of information about network, its operation, and its use; and the central orchestrator must simplify it by providing a layer of abstraction.

Starting from a physical network or “underlay”, a service network or “overlay” automated is built from an orchestrator. An overlay network is still a network that establishes logical paths /ways over the physical network, as does MPLS or other technologies such as tunneling through GRE or IPSec protocols.

Many manufacturers have created their own SDN solution on the WAN and on the LAN, even in some cases without differentiating both environments (SD-Branch or SD-Enterprise). In the solutions catalogue you can find traditional hardware manufacturers (of network or security equipment), or software developers using general-purpose servers as network equipment, although there is a market tendency in the absorption of manufacturers whose solutions are providing better results.

Maybe it is at this point where one of the main disadvantages is found when committing to an investment to address corporate digital transformation. The key word is “proprietary”, without practically resorting to new protocols or standards, since each manufacturer develops its solution, there is no interoperability.

The adoption of SDN on the WAN or LAN by a company not only conditions this part of the network infrastructure, in the long turn, it conditions the rest of the corporate network. Nowadays, the adoption of SDN in a company will go hand in hand with a manufacturer, and the evolution of the network will depend on the roadmap of the selected manufacturer. Once the decision is taken, reversing will be complicated and expensive.

Time will tell us if finally, the SDN WAN and LAN solutions are standardized as happened with other “innovative network solutions”, such as MPLS networks.

Although there is no SDN standard on the WAN and on the LAN, the different solutions share the same purpose, improving the user´s experience. Therefore, roughly speaking, they all share the supported functionalities, although they implement them using different protocols.

What can be the most interesting functionalities according to the type of company?

Multinational Company:

• The complexity of its network lies in the presence in multiple countries with lines of multiple operators and the use of cloud services. In addition to mobility between its headquarters for mainly organizational reasons.
• The new SDN solutions offer homogeneity in services and better agility in the registration / transfer / cancellation of the head office, solving connectivity from day zero and guaranteeing the security of its communications and the connection with the cloud.
• The above-mentioned characteristics, added to the capabilities of these solutions regarding network management, allow a simplification of the administration and operation of the such, and an improvement in the time of resolution of incidents.

Large Company

• Characterized by having a high number of users / devices and / or many locations, as well as, by the adoption to a greater or lesser extent of cloud services. Increasingly, this type of company is also characterized by the mobility of its employees.
• Once again, the construction of this type of corporate network through SD-WAN / LAN environments allows the creation of standard head offices, greater agility in the registration / transfer / cancellation of any head office (with connectivity from day one) and also guaranteeing , the security of its communications and the connection with the cloud natively.

SME

• One of the most common problems in this type of company is the large number of providers they must manage, for a small number of IT personnel: access line provider, security provider (FWs) and internal network (LAN-switches). ), support office tools or applications …
• The new SDN proposals (SD-Branch or SD-Enterprise) seek to facilitate the management and administration of communications and security services: reducing the hardware (for example, if the functionalities of the FWs can be performed from the SDWAN SDLAN solution) , simplifying network management and improving incident.

Drawing 2: Manufacturer positioning – Magic quadrant for WAN infrastructure and for Wired and Wireless LAN Access infrastructure (source Gartner 2020)

Implantation methods

In fact, depending on the specific case, this question may be addressed first or in parallel with the choice of manufacturer or solution.

When implementing an SDN solution on the WAN and / or on the LAN, there are basically three different options: through a telecommunications operator (ISP), through an SDN WAN / LAN provider or set up on its own. Each option raises a series of conditions as can be seen reflected in the following illustration:

Those companies that have their own IT department and / or infrastructure, seem clear candidates to implement a corporate SDN solution on their own. Although in many cases they will not be alone on the way, the manufacturer of the chosen solution will accompany them, and they will even hire an integrator. On the contrary, those companies with a strong dependence on service providers or with managed network services seem clear candidates to implement an SDN solution through an ISP.

Although it will depend a lot on the circumstances, the following describes what the casuistry could be according to the type of company:

• Multinational company: they usually have their own communications department, used to designing and setting up their own network, due to the scarce presence of ISPs at a global level or they can provide a unified solution, at a reasonable cost, to their connectivity needs and security.
• If that was the case, it is best to acquire, design and implement an own SDN solution, independent of a service provider or ISP, and try to take advantage of the benefit of having an underlay network (which could be composed of lines of different ISPs, depending on their geographical availability, cost or technical characteristics) on which to mount the SDN overlay solution. The best would be obtained from each Service Provider and could be easily changed, in case one of them does not meet the service expectations initially set on it (Do it Yourself).
• Large company: given that mainly the category of large company is associated to a certain number of employees, multiple cases could be included in this category. A large company can be made up of a single physical location, a few sites with a high concentration of users in the same area (metropolitan area), or a main site with many location
• Same as with a multinational company, it will be common for it to have its own communications department and even in some cases, its own network infrastructure or multi-operator. Additionally, it could be considering moving services or applications to the cloud and removing that traffic from its private corporate network without impacting its business.

In this case, depending on their size and their IT investment capacity, they can opt for both solutions, or outsource the communications and security services of their corporate network to an ISP or SDN service provider, or set up their own solution by deciding who to hire the connection lines between their headquarters (Red Underlay).

• SME: as they normally are small size, they usually do not have their own network infrastructure or communications department, so they usually outsource the communications service, network maintenance and office automation support.

SD-Branch or SD-Enterprise type solutions allow them to have some control of the network, over which they can act with the initial learning curve. The unification of the WAN network, the LAN network (wired and wireless) and its security itself an improvement in their network experience, that´s why it is this sector that, mainly, contracts these services through a provider.

It will be important to make a good analysis of the starting situation before making a decision regarding the SDN network model to be implemented: identify applications in use and critical types of users and devices who use the network and their behavior, occupation or use of network resources such as access lines, need to undertake equipment renewal or possibility of reuse, etc.

Other considerations

Finally, any IT manager who is thinking about implementing an SDN solution in their WAN and LAN network environment must take into account a series of considerations that can greatly affect both the implementation of the same, as well as its administration and cost. Some of them, but not all, could be the following:

• Subscription model: At this point, perhaps the most notable consideration is that SDN solutions on the WAN and / or on the LAN work according to a pay-per-use or subscription model. Usually each subscription is valid for a period of (1, 3, 5 or 7 years), allows the use of certain functionalities and can dimension the bandwidth of the equipment. The subscriptions themselves vary between different manufacturers, but it is relevant in terms of OPEX (subscription renewal) cost and an element that must be considered in the long term.

 

• Migration by phases and coexistence: Depending on the manufacturer, a migration by phases can be proposed, which provide short-term benefits, with the installation of orchestrators, collection of information on the use of the network and subsequent deployment, interconnecting the new solution with the network traditional. And all this with the aim of providing a better service without impacting the experience of using the network.

It is advisable to analyze, if possible, the reuse of part of the infrastructure, to reduce costs, in addition to trying to reduce the coexistence times of the new solution with the previous network infrastructure.

And what happens with the operation of the solution once it is implemented? Well, on the one hand, this type of solution invites you to define typologies or types of offices and make uniform configurations, in addition to the fact that, based on policies set by the network administrators, the global operation is centrally defined from the corporate network. This does not mean that exceptions cannot be made in the configurations, but rather that, in a way, the exceptions themselves must be regulated. And all this in an automated way.

• New forms of network operation and administration: On the other hand, this type of solution is supported by the telemetry information collected from the different equipment and network elements, information that can be processed and displayed graphically or correlated, indicating plans of action in case of detecting a problem. The performance of the network and / or applications and / or users is measured in real or near real time. Perhaps, in the near future, all this information collected may not only be used reactively, but also make room for ‘autonomous networks’, capable of proactive maintenance based on “baseline” behaviors of applications or users or reacting to events detected.
• A “misleading” simplicity: Eventually, they provide tools to simplify network deployment and to reduce day-to-day incident resolution times. However, the communications infrastructures, far from being simplified, have become more complex to meet corporate demands, thus requiring a greater investment in personnel with greater training and in less routine operation.

SATEC’s relationship with the new SDN environments

Given the growing need of customers to know, design and implement new SDN solutions for WAN and LAN environments, over the past few years, SATEC has implemented a complete training plan for its professionals, experts in the Communications area, with the aim of acquiring both theoretical and practical knowledge in SDN WAN and LAN solutions.

The constant contact with our clients (in multiple sectors and with different needs in their ICT environment), the execution of design projects, approval and implementation of SDN solutions and, finally, training and meetings with different manufacturers of these solutions, we have made it possible to develop a complex methodology for the approval of solutions, designed to be able to compare them and go hand in hand with a company in choosing, designing, implementing and operating the solution that best suits its needs.

To secure this work, SATEC has in its offices different laboratory environments (Demo center) that allow its professionals to test each new advance or new solution that appears on the market, and share this information with their clients, in order to advise them both in the decision-making of the solution to be implemented, as in any need for administration or operation of already operational solutions.

Regardless of the type of company, the solution and the implementation modality, in all cases, at SATEC we are convinced that the new SDN network solutions for WAN / LAN environments provide added value to the current communications of our customers, of Hence, we continue to invest in knowledge to accompany them in their needs regarding these technologies.