We all know; today’s computer networks experience years of movement from technology and architecture to technology and architecture, and changes need to be made in their work. The mobile and video world requires more bandwidth and faster response with minimal delay. This has forced large corporations to react and to utilize a set of new technologies. We still do not know what MPLS networks will be, or how they will move toward Frame Relay and ATM, but it’s clear that WANs will undergo changes and new technologies, and, of course, rebuild existing technologies based on new needs, Are offered. It can be predicted that by 2020, with WAN networks consisting of virtualization technologies and approaches, SDN And there are several WANs with a different but consistent architecture.
WAN problems today
The purpose of large companies is the use of today’s MPLS networks, but some problems with these networks, and of course, the costs and costs imposed on the system and organization, has caused some companies to hesitate to contemplate using it and, at the same time, wait for new approaches. . Some of these problems are as follows: The
cost of privileged TDM accesses (T-1 and DS3) is expensive. Setting up general and global Ethernet networks is simply not feasible, and in many cases will not cost much and will cost a lot to the organization; on the other hand, it is not possible to use fiber optic services everywhere. In the United States, only half of the big and large organizations are connected to fiber optic platforms and can benefit from the broadband services they provide.
The integration of MPLS networks with global Internet infrastructures takes time and discussions such as management and CPE (Customer Premises Equipment) on these types of networks will not be available soon. We all know that any organization in the first place needs an Internet connection and high-speed connections. Here we need smart, fast and powerful services to connect to the Internet, while MPLS networks are often not ready for this purpose.
The MPLS itself does not require much time and time management, but the situation in CPE-enabled networks is different, and the devices based on it require a lot of network management infrastructure.
Today, we are witnessing the welcome to services and software like Skype, in businesses and apps based on Cloud, which has changed the capacity and management of organizations. The need for powerful cloud-based software and applications clearly delivers network-oriented orientations that make WAN traffic more intelligent and faster and more sophisticated.
These problems and shortcomings and the lack of ability to meet the needs of new organizations have led companies widespread to embrace new approaches such as SDN, virtualization, and WAN, because they expect these technologies to reduce the cost of current MPLS networks. It is likely that we will be talking about the practical benefits of these technologies, but there is no doubt that in the years ahead and by 2020, we will see changes to the architecture of today’s WAN networks, and we must be prepared to face up to these changes and be aware of the specifications of the future networks.
The basis of SDN’s work is to isolate the network’s brain (control) from the shell (data transfer). Here, the main actor is the architecture of switching computer networks that will be found by 2020 in most of the running networks. The router is the main body of a modern computer network that receives a stream of information and must send it to a specific path based on its routing tables. In the old equipment and especially in the world of Cisco routers, a router must not only have routing operations on the network, but also have to integrate many of the control parameters of the software and operations for certain applications.
In the world of software networks, a central controller is responsible for the entire network’s management, and plays the role of the brain and the software for implementing anything. Most of the time, this central controller is an open source software; among other things, routers are less intelligent and often use very low-level applications that only have the ability to direct information based on the routing specified by the central controller (Figure 1) . In SDN, these routers or switches may be deployed on a virtual network, and even do not have a physical router / switch; in fact, the SDN world is tied up with virtualization and is not applicable without the use of virtualization technologies and techniques. . In sum, SDN attempts to separate the network control from the flow of information. This may not seem like a big idea; it makes a lot of difference in financial concepts and technical implementations.
Figure 1: SDN technology separates information control layer from data transfer layer. In the image of the relationship API is high-level network applications with the central controller and the hardware underlying layers of the network.
First, the cost of routers in the SDN architecture is much lower, and in some networks, less than half the cost of routers. Many of these routers, with the central controller, are deployed virtualized using open source software, which is much cheaper than the software and controllers of dedicated codecs like Cisco and Juniper. The cost of purchasing and launching a WAN today may seem to be low for many companies, but in the medium term, and especially in the long run, this cost will be huge, since maintenance and updating of the exclusive physical routers is very costly, as well , The development of such networks requires a high level of funding based on the needs of each sector.
Second, if you want to install a new software on the network or make a major update to the network, you will have to install this software installation or update on hundreds and thousands of physical routers, but if you switch to SDN, only You need to install or update a central controller software, or ultimately, you need to update two or more central controllers. Faster, these central controllers are cheaper and have much less error rate; besides, the development and evolution of a software-based network is much faster and easier than a network of hundreds of hardware. It should also be noted that the central controller provides the characteristics of the standardization and automation of the network, resulting in a reduction in manpower and network maintenance costs.
Third, central controllers can be used much more efficiently than the WAN broadband, because these controllers can well view and direct traffic across the entire network. These controllers know the flow of information from which source, and which source is coming along the path. By switching to SDN on one of its large and widespread networks, Google managed to increase productivity from 60% to 95%, while the cost of this WAN dropped by half in each segment. Central controllers allow network engineers to customize and manipulate network traffic according to the needs and requests of an organization. These engineers can change the traffic of any software at any time of the day, and if it enters an over-capacity port or traffic path over a given time period, it will overcome this dilemma with new routing.
They can even reroute the network instantly and in real time so that no port or path is dropped out of the network; therefore, the scalability of SDN networks is much simpler than traditional WAN networks.
WAN combination networks not so fresh but improved
SDN concepts and virtualization (although this topic is more ancient than SDN, but new routers in broadband networks, a new topic) have recently been used in the area of data centers and network and Internet service providers, but in WAN networks Do we see new approaches and what changes in the next few years? When SDN components are implemented and implemented in an existing WAN network, the control and intelligence area of the network will be separated from the underlying layers of data transmission. As a result of these developments, some of the concerns and challenges of WAN networks, such as the critical recovery conditions in small businesses, increased application performance (based on Cloud), the rapid addition of new places to online services and the provision of the Internet, and ultimately, network configuration without cost too Will be resolved.
Hybrid WAN It’s a new concept that comes up with the emergence of Cold Services, which will launch high-speed Internet but at a cheaper cost. Combined WAN networks try to combine and integrate traditional data transfer networks (including MPLS) with the use of broadband and dedicated Internet access; in other words, the new approach of WAN networks creates two links and connects to a site based on traffic types and parameters Performance is defined. This achievement can be extended to other parts of the network; for example, a combination of WANs can be used to connect remote sites to organizations with lower costs, but broadband and the Internet are faster to use; also, organizations that need to set up long distances (several hundred kilometers) Expensive among several branches, they can take advantage of the new generation of WAN networks.
Figure 2: An overview of future WAN networks that are also known as SD-WAN. In the picture, it is possible to manage MPLS, wireless, and cable broadcasts using central control layers.
WAN combines better utilization of LTE wireless services even in MPLS networks; hence, users of these networks can access MPLS dedicated broadband for applications; as well, the number of ports and less equipment used Which reduces total system costs. In some cases, new WAN technologies help to make existing MPLS bandwidth more efficient and effective, and consequently, we do not need to expand broadband. For many widespread companies, the combination of WAN has the opportunity to change the architecture of the network, with the goal of greater access and broadband access to the Internet, and can then provide high-speed Internet and cloud services.
Hybrid WAN technologies have been introduced before SDN and can be implemented without the concepts of software-centric networks; however, routing settings and policies were to steer the network traffic to a fixed and uninterrupted level, and network engineers could not implement dynamic routing based on network requirements and traffic loads. . When SDN is added to these existing technologies, managing and routing a network is made possible by a central controller or one location, and significantly improves the concept of WAN connectivity. As mentioned above, SDN with a central controller simplifies network management and can be configured faster and easily. This also applies to telecommunications equipment and branches away from the central office, and features such as improved selected or prioritized routes, better monitoring, cheaper CPE, and faster / easier updates (because only the central controller is needed and more with hundreds Remote router, do not do anything). All in all, SDN makes the WAN technology more complete and functional.
Now that it has been somewhat clear in the future what WAN networks are going through and which technologies and innovations will be added, one should look at the issues raised in this regard:
CapEX related to new hardware and software: Fortunately, network engineers are well aware of how to move a traditional network to SDN without imposing costly, system-wide charges. Many companies are worried that to use SDN, they must change the entire network infrastructure and buy new hardware / software. In practice, the SDN can be implemented gradually and step-by-step in a traditional network.
Lack of SDN engineers: this is always the case for moving from a traditional network to a modern network; if this transition occurs over several years, in the medium term, we will see the deployment of technologies and equipment in large servers, integrated systems, and many From the implications and initial facilities of implementation and to some extent, the concern for specialists and possible problems is resolved.
Service Levels: Internet access services (such as mobile services) are provided without clear, transparent SLA services; but the lack of different levels of service in the transmission network layers does not mean the loss of service quality; it means that your engineers can network By controlling and managing parameters such as traffic priority, optimized routes, and network driven routing or errors. Servers can provide proprietary Internet access rather than providing a clear, transparent price tag for each client, rather than ensuring that each user’s bandwidth is observed.
Broadband and its clashes: Usually with cable broadcasts, a set of subscribers close to each other was fed from a ninety and shared connections. This means that the traffic of a site with the traffic of other shared sites in a ninety, will compete. Here are the unbreakable broadband issues and the differences in uplink and downlink speeds. In the future, high speed optical fiber-based services such as Google Fiber (at a speed of 1 Gbit / s) will have a huge impact on networks and solve some broadband problems. Customers who need real-time services and any widespread decline will disrupt services, go to Google Fiber and so forth, and no longer engage in speed issues on broadband broadcasts; of course, services like Google Fiber are not yet comprehensive and are broadly based on Not available to anyone.
Broadband Accessibility: Internet connectivity will remain available, and businesses that now use these services can still use these Internet access, based on their needs and speed and traffic levels. The goal of future WAN networks is not to dismantle these services, but at a higher level, they want to provide more broadband access at any location, even where cable broadband services are not available.
Contracts: Certainly, new contracts will be different from previous contracts. For example, you will need two types of contracts on future WAN networks: 1. A contract for the development and negotiation of a central SLA controller based on the benefits provided by SDN engineers who can well provide the services you desire. 2- Designer / Transmission time from traditional network to SDN WAN so that loss or damage to existing services is not affected or interrupted. You may go to the new and less-known companies in the market to conclude contracts, and you have to rely on them; also, you must have contracts for adapting the solutions and technology of various equipment to ensure that you continue to work and when developing the system, Do not miss the system’s incompatibility issues.
The near future, may be 2020
Currently, mass-media companies are using the public Internet on layers of WAN networks and use techniques such as tunneling or encryption for information security, but it seems that some companies have started to combine WAN and SDN to reach more modern networks. And by the end of this decade, we will see such networks. Cloud-based applications are in great need of broadband; information is naturally growing and productive, and the problems of integrating fixed networks with mobile networks are not yet resolved; on the other hand, the annual budget of companies is declining and they tend to cost Spend less on IT, but need to upgrade the network and provide newer services. Efficiency and efficiency have become more important and not just a value-creating network.