Currently, the proliferation of robotics in practically all areas, the commitment to intelligent systems supported by artificial intelligence technologies or machine learning, the new platforms gaming, global collaboration platforms, telemetry platforms based on IoT, or telecare services are clear examples of initiatives in which digitization has led to a transformation in the way we interact with entities, institutions, services or even with others. But this is only the beginning.
The next thing will be platforms for interactive 3D games with augmented reality with players distributed throughout a country; telesurgery systems for 100% remote hospital care in dangerous areas; management systems for road freight transport with driverless trucks; facial recognition and identification systems in crowds, or global control services of autonomous cars with analysis of group behaviors and conditional response. And all this based on cloud platforms with worldwide applicability, and with basic aspects such as activity control, security, or guaranteed regulatory compliance.
The networks and systems that support this deployment must offer communication channels to the end terminals with capacities ranging from hundreds of megabits to several gigabits per second, and end-to-end connection delays of a few milliseconds.
Optical access networks make it possible to reduce the number of nodes in the access layer, so their complexity is reduced thanks to the greater distances that can be reached in the “last mile” with fiber technologies. However, the new use cases require high levels of demand in technical parameters, in addition to high levels of mobility. Therefore, the fiber is not enough to satisfy a potential future demand. 5G has arrived.
5G is much more than a 4G with more capacity. 5G, unlike predecessor mobile technologies, raises improvements in communication capabilities, which implies a major transformation in the networks of the telco, the use of higher frequencies and the optimization of delays.
The use of higher frequencies called millimeter waves (mmWave) allows to achieve bandwidths above 10Gbps, but has the serious drawback of high signal propagation losses, and signal shielding by common elements such as walls, vegetation or even people themselves. This factor means that the size of the cells of the 5G networks must be smaller to offer much greater transmission capacities than with the 4G network.
To optimize delays in 5G networks, changes must be applied at different points in the network, but end-to-end delays must be significantly reduced to accommodate uRLLC applications, which necessarily involves bringing network services closer to devices. end. But that supposes the multiplication of the number of active elements that make up the networks and therefore, and in a significant way, the costs of their management and maintenance.
In 5G networks, the functions of the MME (in charge of managing the mobility of connected devices (User Equipment – EU) have been distributed among 3 different elements: the AMF (UE Registration), the SMF (Session Management – PDU), the AUSF (UE Authentication). The functions developed by the S-GW and P-GW elements in 4G networks have been distributed between the SMF (control plane) and UPF (data plane) in 5G networks.
All the elements defined for 5G networks have been designed to be executed as VNFs (Virtual Network Functions) – about architectures Cloud based on standard virtualization platforms on the market, and on general purpose hardware. This design provides all the flexibility over the network to be able to offer the characteristics directly related to the increase in capillarity of the network.
The ability to host virtual systems within the company’s own network telco It also opens up a world of possibilities to offer your own value-added services or to market those of others. Virtualization infrastructures will have to be deployed across multiple network nodes, generally in a multi-tier data center architecture. Thus, the architectures Cloud deployed within this network must have the ability to support the typical life cycle operations of a VNFs and allow deployment, monitoring, scaling (up or down), remediation, startup, shutdown and archiving of any of them, maintaining control over the underlying resources at all times.
Currently, the VNFs available on the market are marketed with compatibility with the most relevant Cloud technology providers, especially considering architectures Openstack, products that are being migrated to a greater extent to container architectures.
The massive deployment of Cloud technologies within the networks of the telco, together with the virtualization of network functions, allows functions to be dynamically deployed where they are needed and to adjust their size to the demand of the specific node where they have been deployed, to optimize the amount of resources consumed by the function in general terms, and the consumption energy of the network in a particular way.
Bringing virtualization to elements of the fixed network such as OLTs, BNGs, or CCAPs implies, however, facing additional challenges to those derived from these technologies in mobile networks. Fixed networks are an ocean of different access technologies in which any telco makes different combinations of PPP, IP, Ethernet, MPLS coexist, while generally dragging an environment legacy where even older technologies coexist.
Current fixed access networks are adapted to these environments, however, taking this to a virtual environment means bringing all the variety of typical traffic encapsulations in these networks to datacenter environments in which the network infrastructures have to be capable of drive this traffic to the physical servers in which the corresponding VNFs are deployed.
Faced with a potential increase in the number of nodes and systems integrated in the network, and therefore, the number of manageable elements of the network, it is especially desirable to guarantee the manageability of the entire environment, and also, that the operating costs of the network management of them are maintained or even reduced. To improve this aspect, telco have developed optimization mechanisms based on the basic principles of software-defined networks or SDNs.
The first initiatives that drove the emergence of software-defined networks were based on the concept of making network elements cheaper by separating the control and management planes from the data planes, in order to execute the first in general-purpose hardware elements and low cost. This principle has been applied to new network architectures in the telco in what has been called CUPS (Control-User Plane Separation). CUPS proposes the existence of multiple control and management planes (CP – Control Plans) concentrated in specific control instances running on virtualization platforms, and controlling several remote units that concentrate the data plane (UP – User Plane). CUPS architectures make it possible to reduce the number of control and management planes by grouping those of several network elements into a single instance, and open the door to coexistence in real networks between physical and virtual PUs.
The generalization of Cloud architectures within the networks of the telco It is an opportunity to contain the operational costs (OPEX) of the transformation in a projected future scenario.
On the other hand, in a competitive scenario in which, for example, the ARPU (Average Revenue Per User) of mobile services has been stagnant for more than 5 years, the telco They see in the evolution of architecture a way to increase the added value of their offer to the market, in sectors such as the automotive or healthcare sectors, capable of generating a high volume of income indirectly.
There are still numerous factors in the a
Iire that will condition the infrastructure transformation model and the business models themselves. Will the transformation be interesting in terms of costs? When will mobility applications, health, automotive, etc be mature? How to make current personalized services coexist with the massive management models fostered by Cloud technologies? How to maintain operations in a future scenario with a shortage of personnel with a technical profile? Questions that will be resolved in the near future rather than the distant future.
Signed: Marcos Míguez, senior consultant in telecommunication networks at Grupo SATEC