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Web Apps with Python and Flask using Web Forms

We know that Python programming language can be used to create CLI applications. But, in most cases, CLI applications are used on your local PC.

There are examples when we want to present our calculations or some results in a form that might be suitable for the Internet. To achieve this we need to build a webpage.

In our scenario, we are presenting an example of using Flask and Python script that interacts with our written HTML code. As an option when we can take user data, entered from a webpage, we use WebForms.

There are a few things that you need to think about before you start building your first web app with Flask and Python. First is choosing a suitable Python IDE and build a virtual environment with Flask and Python. Next thing is to see how your Python script will route to the specific resulting  URL. And of course, using Jinja2 templating to use variables that interact with values between Python script and HTML code.

Bellow is our free code example for a basic Web app that calculates Summation or Product of a sequence.

Visualization of Network Device connections with Python

In many occasions during network design, network administration or troubleshooting of the network we are dealing with the issues: – How to visualize our network?. Reasons for this can be many, starting from different operating systems of devices, different vendors etc. And because of these and many other reasons that might be obstracles, we can’t represent our network topology using network software.

To avoid manual drawing of the network topology we are showing you example how to use power of Python coding to achieve this goal.

In this Lab example we are providing option to use Excel template file ( 1. Template of devices Next Hopes) where we may populate data needed to visualize our network. This file can be shared between the collegues in the enterprise or telco companies and data can be recorded.

Using those data we are able to implement intermediate Python coding to read those data from excel document, which is created in a format as template and if you follow instruction how to use this format it doesn’t matter how much network devices you enter or how many Next Hopes are per specific device. Code is designed to accept data and translate them in a form of dictionary.

Data in this dictionary data format later might be changed in other formats like List, or to represent their Key data separately and Value data separately as well. In our case we use {Key1:[Value11, Value12, …], Key2:[Value21, Value22, …], …} dictionary form.

What is next used, is Graph representation – connection between devices (called ‘edges’ in the Graph theory). Of course, network devices are ‘vertices’ (nodes or points) regarding Graph theory.

To be able to Visualize network connections between devices we use NetworkX Python package.

Lab code and details can be found in the following document: 1. Visualization of Network Device connections with Python.

First technical problem with our web page

Today we have experienced, the first time from the beginning of the Centrium Tech LTD web page, problems with our Centrium Tech LTD blog and Centrium Tech LTD Academy.

Problems were from technical nature and multiple technical issues were solved and now we can offer you a secure connection to any part of our linked webpages.

Thanks for your patience.

Centrium Tech LTD Support Team

How to use Bash Scripts and Python code to create a project?

We know that during writing Python code, sometimes because of lack of programming experience, or because of short deadline or because of the complexity of the output format of data from Python code we may use as support Bash Scripts to achieve our planned goal.

Depending of our needs in Bash Script we may execute one or more Python codes, or we can collect output from a Python file and we will process it and create the result we expect.

Bash Scripts can be useful especially in cases where we need to analyze some text saved in a document and sort data from it. So, during this process of creating your project, it is useful if you can create temporary text files and later in the Bash Script you will remove them. The intention is to store some changed data in the new file, and after the operation is done this file is no longer needed. In this case, you do not create new documents that will be junk files.

As an example we will present a simple project, that plots all (X, Y, Z) dots that solve the equation:


To understand the solution for this equation, we know that integer and float numbers can be a solution to this equation, but also there are complex numbers that can satisfy this solution.

This example is shown in the following document x2+y2=z2

FAQ for Network Programmability Online Course

1. What is the content of this Course?

Network Programmability Online Course presents an understanding of Debian Linux: basic commands, network commands, writing basic Bash Scripts and automation using Bash Scripts. Also, there is a need for understanding Python programming language as starting point for network programmability: basic syntax, data formats, interaction with network devices and translation to different data formats, creating Python scripts for network automation. Also, there is a significant number of code examples, either written in Bash Shell or Python code or presentation of how to use Linux network automation/telemetry tools. These learning labs present a wide portfolio from basic examples to the overall scenario to manage network devices for network programmability, enabling network automation or model-driven telemetry.

2. How the process of learning will be achieved?

After we will provide you with learning materials/labs, the process of learning is through open interaction with a personal instructor in online video communication.

3. Are these codes usable for real network automation?

Sure. It depends on the scenario if network tools are used, or Python code is written, or even Bash Scripts are written for this.

4. How in these learning labs is presented interaction with network devices?

Practical examples are basically guides on how to check the capabilities of network devices, which protocols we will use to ensure reliable communication to any of them and how to prepare them to be managed as a group of devices presenting the use of Templates.

5. Who has to attend this course?

Usually, network administrators need to satisfy their curiosity in an unknown field for them. But also, it might be useful for developers that got experience writing code, but have a lack of knowledge of how to interact with the various network devices (either different vendors or because of their different versions of operating systems).  Also, students are more than welcomed, because they will know ‘How to do it’ after they have read theory or news about technology.

6. Are there learning labs where network tools are used?

Yes. There are examples of various network tools used. You will get info on what they are used for, and how to use them. Also, the comparison between them, which to use or which to prefer in a specific scenario.

7. Are there will be updates of these materials with new tools or approaches, if available?

Of course, we check any updates on the development of the network programmability. If we find a network environment that might be used to create a learning lab to check the abilities of new network tools, that will be done and added to the other learning labs.

8. If we need special questions for a specific solution in our company, will you be able to provide support?

If you need to test network environment, or you need to ask for an optimal/workable solution, we will provide our support for you, offering you our consultancy services for extra fees, especially for telecom operators that need to change their administration of network to be mostly done remotely by their employees.


Laser Safety Officer certification

Laser Safety Officer certification can be earned after passing the online certification exam inside the  Academy Centrium Tech LTD platform.

– Prerequisites – To be able to take this test and gain a certificate, you must have a minimum of previous 5-year working experience with optical telecommunications networks or have worked near telecommunication laser equipment. It is desirable (but not mandatory, if you have relevant working experience) that the candidate possess a university degree in the field of electrical engineering or telecommunications. Any person who wishes to be tested to have the opportunity to obtain a Laser Safety Officer certificate must have completed a prior laser safety training, and to provide valid evidence for attendance issued from our company or from another training company.

– Online test – Before testing, candidates are given a unique online link where the test is set up, only for them. The candidate is registering on the test platform. The test consists of 25 unique questions, created by CentriumTech LTD. Questions contain text, images, or tables from which it is necessary to find the result of the calculations. The answers to the questions are with one correct answer, two correct answers or more correct answers to be selected (to be chosen). More complicated questions require candidates to make calculations to get the right result. Upon completion of the test, the test platform automatically informs the candidate of the results of the test.

Completion of testing and validation of results – Upon completion of testing, in the test platform the results of each candidate remain. They are reviewed by CentriumTech LTD and if there are at least 85% accurate results finally it is confirmed that the test is successful. If the result is below this limit, the test can be repeated. CentriumTech LTD introduces a rule of opportunity for a candidate to be tested a maximum of 3 times. In case you do not pass the test three times, due to the sensitivity of the Telco Laser Safety, and in order to ensure quality workplace protection, CentriumTech LTD does not allow this candidate to obtain a certificate for the Laser Safety Officer, so it will have to seek a test facility with other companies if it wants to acquire a similar certificate.

– Certification – In the case of the test success, the candidate will be informed within 14 days that he has obtained a certificate for the Laser Safety Officer and will receive it in electronic form. The certificate is in a unique form, indicating that the person is a certified Laser Safety Officer. If the candidate wishes to receive the certificate in a written paper, he will have to deposit the delivery address and pay further for printing the paper version of the certificate and its delivery to the address.

– Certificate validity period – The Laser Safety Officer certificate is valid for a period of 5 years.

Our new Telco Laser Safety products

We can offer you two products related to Telco Laser Safety:

1. Telco Laser Safety Documentation Toolkit

2. Telco Laser Safety training

For more information about these products, you are able to check the FAQ below.


1. What is Telco Laser Safety?

Telco Laser Safety is an overall process of measures and activities that an organization, which offers or use telecommunication services, accepts to avoid or decrease the risk from laser eye or skin injury in the working place.

2. Does Telco Laser Safety cover all types of lasers in all industries?

Telco Laser Safety gives directions and related information for Optical Fiber Communication Systems but doesn’t cover all possible laser use. It is applicable just for telecommunication lasers. That means applicable to telecommunication operators and companies that have implemented optical fiber communication technology through the use of laser equipment.

3.  What is Telco Laser Safety Documentation Toolkit?

Telco Laser Safety Documentation Toolkit are documents prepared on the base of the IEC and EN accepted standards and technical reports that treat Laser Safety in Telecommunication networks. Those documents are policies, procedures, Guides and Forms that organization which operate and maintain Optical Fiber Communication System accepts and integrate into their management practice.

4. Who is responsible to sign, maintain, upgrade these documents from the Telco Laser Safety Documentation Toolkit?

In the operating organization responsible for preparing, handling, maintaining and upgrading those documents is Laser Safety Officer. But, some of these documents are accepted and signed by the organization management.

5. What is a telecommunication organization committed to, when it accepts Telco Laser Safety Documentation Toolkit documents?

Telecommunication organization is declaring a commitment to calculate risk from an eye or skin laser injury, to implement safety measures and to provide adequate Telco Laser Safety training to the personnel that operate, maintain and service OFCS parts. Actions that the organization accepts are listed in the documents which are part of the Telco Laser Safety Documentation Toolkit.

6. What is Telco Laser Safety training?

Telco Laser Safety training contains materials that explain the basics of the optical fiber networks technologies, in regards to Laser Safety. That means which types of laser injuries can occur and on which OFCS location positions, which is affected by these injuries mostly, what are the OFCS location types, how the laser equipment is classified, how laser Hazard Level is evaluated, how the optical technology influence on the Hazard Level, which laser parameters influence the increased risk from injury, how to assess and calculate hazard level, how to chose, use, maintain and replace eye or skin protective equipment, and also how and where to implement labels, markings, additional information, administrative controls etc.

7. Is Telco Laser Safety training obligatory to all companies that have OFCS?

Telco Laser Safety training is targetted at companies that have personnel that operate, maintain and service OFCS parts. Mostly these are telecommunication operators and companies that integrate OFCS, where there is a high Hazard Level found in one or more than one OFCS locations. But, Telco Laser Safety training is recommended as well for telecommunication operators and companies that integrate OFCS, to be able to avoid possible laser injuries from operational misuse or operation of non-trained personnel.

8. What those that attend this Telco Laser Safety training will learn?

Telco Laser Safety training contains multimedia written and spoken materials that provide significant information to attendees to understand the terminology of Laser Safety, to understand laser equipment types and OFCS parts in regards to laser safety, to know to read instructions and directions, to be aware of the safe operational practice and to provide adequate personal protection in the OFCS location positions with high risk from the laser-related eye or skin injury.

9. In which ways you can attend Telco Laser Safety training?

Telco Laser Safety training materials are multimedia materials that provide precise instructions and guides. Companies or telecommunication operator that are interested in Telco Laser Safety training are able to receive those materials as a digital copy and later are able to share them with its employees as learning data or through the presentation in internal Telco Laser Safety training. Also, there is an option to contact us and later to receive a link where Telco Laser Safety training materials will be published online only for your needs. And finally, we are able to provide you with seminars or webinars on the subject.

10. Are Telco Laser Safety Documentation Toolkit and also Telco Laser Safety training free or there is a need to pay for any of them?

These materials are professionally based materials intended just for the companies that integrate telecommunication laser equipment and are not free. For the price and related questions for Telco Laser Safety Documentation Toolkit or for Telco Laser Safety training, you can freely contact us at

Free online certification for Optical Networks Design

CentriumTech LTD Academy has a new module, for free online certification. Its main goal is to fill the gap that existed in Optical Networks Design field certification.

This certification program is open to any individuals, as students or professionals in the field of telecommunication optical networks design, that need to prove their knowledge and attain the certificate. This certificate program gives an opportunity to recognize telecommunication students and professionals as an expert in the field and that they are ready to work on Optical Networks Design.

Certification test that has to be passed, with at least 82% correct answers, contains questions that for someone looks easy at the first point, but some of them are kind of tricky. So, experience, knowledge, and research have to be combined together to be able to be successful in this test.

After finishing this test, you need to fill your details and most important your e-mail address, for us to be able to contact you later if you successfully passed the test. All successful candidates will receive later, no more than two weeks, their earned certificate.

If you like to attempt for 2nd, 3rd, … the 9th attempt on test use new username credentials, For example, if your 1st attempt on the test was with username ‘randy’, the 2nd attempt on the test should be with username ‘randy1’, etc.

Questions in the test for Optical Networks Design may be changed at a random time, but at least once a week.

We have to give courage to all telco students, telco professionals and design engineers that have interest in the field to earn this certificate and prove their knowledge for Optical Networks Design, that might bring them success in the future working career.

Optical Networks Design certificate is valid for 5 years, from the day that you successfully finish a required test.

If you want to test your skills in Optical Network Design and earn a certificate, follow this link: Free online certification for Optical Networks Design.

Wi-Fi evolving

Wi-Fi technology is evolving and improving capacity limits. New standards become available even in hardware, so the new momentums are coming for the enterprises. Using of a lot of wireless and mobile devices in the working areas increases the demand for Wi-Fi capacity for the enterprises.

There is an enhancement of the Wi-FI 802.11n standard with newer W-Fi 802.11ac standard (Wave 1 and Wave 2 products). Wave 1 products support 20MHz, 40MHz and 80 MHz channels in the 5 GHz free Wi-FI band and also for backward compatibility with 802.11n there is an option using 2.4GHz band.

There is more channel bonding (in Wi-FI 802.11n standard was 40 MHz) and now is even 80 MHz or 160 MHz, which gives the speed of 433Mbps, 867 Mbps or 1300 Mbps at the physical layer. Wave 2 products speed is going to the 3,47 Gbps.

Already on the market, there are 802.11ac Wi-Fi-enabled laptops from Dell, Lenovo, HP etc. Also, there are 802.11ac Wi-FI routers from Netgear, D-Link, Linksys, etc.

There are more MIMO (Multiple Input Multiple Output) – Wi-FI 802.11n standard uses 4 spatial streams and Wi-Fi 802.11ac standard goes with 8 spatial streams. Wave 2 products will come with new technology Multiuser MIMO (MU-MIMO), which gives the possibility for sending multiple frames for multiple clients at the same time on the same frequency spectrum.

Wave 1 products can support 256QAM in an environment with low interference, which gives the possibility to use HD streaming between devices in the same room.

Wave 2 products are planned to be backwards compatible with Wave 1 802.11ac Wi-Fi devices. This evolution arises from the planned needs of the homes in the near future where there will be a need for connecting around 20 Wi-Fi devices in the home.

New companies arise from JDSU

JDSU announces that it will be separated into two different independent business entities, later this year. That will make the disappearance of one recognized brand.

Here is a statement on their web page:

On September 10, 2014, JDSU announced plans to separate into two publicly traded companies. Lumentum Inc. will include JDSU’s industry-leading Telecom, Datacom, Commercial Lasers and 3D Sensing offerings. Viavi Solutions Inc.​ will include JDSU’s network and service enablement solutions for the Service Pr​ovider, Cloud and Enterprise markets and JDSU’s Optical Security and Performance Products that help organizations fight the battle against counterfeiting.

The decision to separate will allow each new company to be more agile and focused on their customers and markets, while generating long-term value for shareholders.​​​​​​​

“The creation of new brands and the Form 10 filing are important milestones as we move toward separation,” said Tom Waechter, president and chief executive officer of JDSU. “Each company will remain committed to continued innovation and will be led by proven management teams prepared to execute growth strategies designed to help our customers successfully manage the complex opportunities that come with the ever-accelerating pace of technological change. We are creating two unique brands – both representing well-established expertise and market leadership – and positioning them with greater customer focus and agility.”

More on this topic you can find on the following link.