Ray Tawil
Software Developer, Equity Analyst, Polymath.
What is network security?
3 weeks
by Ray Tawil
in Network Security
- What do we mean by network architecture?
- What are the most widely used architectures in computer networks?
- What is a protocol and why is it needed?
- What is a network protocol and what does it contain?
- What are the significance and the role of a protocol in network architecture?
Network architecture encompasses the design and layout of a computer network, including both physical and logical components and how they interact with one another. The most commonly employed architectures in computer networks are client-server and peer-to-peer. The client-server architecture includes one or more central servers that provide services to multiple clients, while in a peer-to-peer architecture each device on the network functions as both a client and server. Protocols are a set of guidelines and rules that regulate communication between devices on a network, which are necessary to ensure devices can communicate effectively and efficiently and prevent conflicts and errors. Network protocols include rules and guidelines for transmitting data over a network, including the format of the data, how it’s broken into packets, and the routing of packets through the network. Protocols play a vital role in network architecture, as they are the foundation of network communication and without them, data would not be able to flow between devices. They permit devices to communicate with each other, regardless of hardware or software and ensure that data is transmitted accurately and efficiently. Additionally, a good protocol allows for easy scalability and troubleshooting of the network. In conclusion, protocols are necessary for smooth communication and coordination within a network, without them it would be impossible to transmit data between devices, they are the backbone of network communication, ensuring accurate and efficient data transmission and enabling communication between devices regardless of hardware or software.
My take on The war between Ukraine & Russia – simplified
0The modern ongoing conflict between Russia and Ukraine began in 2014, when Russia annexed Crimea from Ukraine. This move was met with international condemnation, as it was seen as a violation of Ukraine’s territorial integrity.
Since then, fighting has erupted in eastern Ukraine, primarily in the regions of Donetsk and Luhansk. This conflict, often referred to as the “Donbas War”, has resulted in thousands of deaths and displacement of civilians.
The United Nations has reported human rights violations by both sides in the conflict. The UN has documented instances of the use of prohibited weapons, such as cluster munitions, and targeting of civilians by both Russia-backed separatists and Ukrainian forces. Additionally, there have been reports of arbitrary detention, torture, and enforced disappearances by both sides.
The international community, including the European Union and United States, has imposed sanctions on Russia in response to their actions in Ukraine. Despite multiple ceasefires and peace agreements, such as the Minsk agreements, the conflict remains unresolved and tensions continue to escalate.
In 2020, the UN reported a significant increase in ceasefire violations, with both sides accusing the other of escalating the violence. The COVID-19 pandemic also added to the already dire humanitarian situation in the region, with many residents in conflict-affected areas struggling to access essential goods and services.
The annexation of Crimea and the ongoing conflict in eastern Ukraine have also had a significant impact on the relationship between Russia and the international community. Many countries have withdrawn their ambassador from Russia and have imposed sanctions. The US and EU imposed several rounds of sanctions on Russia, targeting individuals, companies, and sectors of the Russian economy.
The situation in Ukraine remains tense, with both sides accusing the other of aggressive actions. While the ceasefire agreements have reduced the level of violence, the underlying issues that led to the conflict remain unresolved. A peaceful resolution to the conflict is urgently needed to bring stability to the region and to improve the living conditions of those affected by the war.
It’s important to note that the conflict in Ukraine is a complex issue with a long history and multiple perspectives. While you might a person or a country’s perspective, it would take lengthy research to establish a clear picture and a complete understanding of the conflict.
Why are gas prices at the pump not directly correlated to crude oil prices?
While the overall trend in the graphs seems correlated, the contrast lies in the details. If you look closely, the disparities will stand out. You will notice that the prices are not bound only to supply, demand, and the price of crude oil. Crude does not entirely affect the price at the pump most of the time. Below are a few factors that interfere with that relation:
Commodity Trading: In the stock market, you have people that trade futures for commodities like oil, gold, and sugar. These future stock traders buy contracts from the commodity seller for the price that they anticipate the commodity will sell for in the future. When traders do that, they are moving the price for the gas in directions, sometimes utterly unrelated to the market oil price, because they are creating a price bubble based on pure speculations.
Taxes, Tariffs, and sanctions: While the price of oil might be low, imposing a tariff on a specific country can cause a price jump for the importing country consumers, although the oil price might be low worldwide. Another example of high prices for gas at the pump that doesn’t relate to the oil spot price can be specific taxed locations. As of July 2019, California, for example, charges $0.55 per gallon as a gas tax and an additional 23.7 percent sales tax, while Mississippi charged a $0.18 gas tax per gallon and a 9.8 percent sales tax (Stebbins, 2019). Sanctions are also another example of affecting prices at the pump. At the same time, the United States imposed sanctions on Iranian oil in 2018-2019 did not benefit the USA on the pump, the European Union benefited greatly from the U.S. sanctions by buying cheap oil from Iran.
Scarcity and Abundance: When it comes to the Oil price, there are additional factors to take into consideration. Oil price reached an all-time high of $165.20 in 2008, world oil reserves were increased year over year but would not reflect the price of $20.19 an all-time low in 2020 (Bloomberg, 2020). Since the reserves did not increase significantly and the demand is higher because the world population is increasing every year, add to that the increase in appetite for the developing nations for oil consumption due to economic expansion and growth (U.S. Energy Information Administration, 2020). The question becomes, how do abundancy and scarcity come into play in the oil situation? Since the amount of oil we have on the planet is not increasing and we don’t have discoveries of new oil fields, we conclude that the scarcity of a commodity such as oil is dependent on the other factors. Factors like politics, wars, and production come into play; therefore, in this situation, oil is abundant but can be scarce depending on several factors (Macrotrends, n.d.).
Government Regulations: Take a regulation like tax breaks for electric vehicles. This regulation can help ease the consumption of gas at the pump. This government regulation can interfere with the price of the gas relative to the price of crude oil.
Gas Additives: In the USA, gas additives can severely affect the price of gas. The number of additives can hide the initial cost of oil. For example, ethanol additives account for about 10-15% of the gas price in the U.S. (U.S. Energy Information Administration, 2019). Although this additive is incredibly cheap in the USA because it is extracted from corn, a local produce, it can be expensive somewhere else.
Currency Valuation: While oil prices might drop, a country that has shaky finances with its national currency can have its citizens end up paying more for gas at the pump, especially if the country is an oil importer (Farley, 2019).
Refining costs, retail markup, and transportation expenses: If you take Alaska as an example, While Alaska has the lowest gas tax price, the lowest sales tax across the USA, it has the 4th highest gas price. This is due to the fact that Alaska is so remote and has limited refineries (Minemyer, 2018). The increased need for transport in remote and harsh conditions makes the retail markup high compared to other states (Minemyer, 2018).
As we can notice, several factors affect the price of gas from the time it is crude oil to the time it reaches the pump. Economic, social, technological, and trade factors all come into play to regulate the price of this commodity that has made some countries flourish, and others get torn apart.
Reference
Stebbins, S. (2019, February 5). How much gas tax adds to cost of filling up your car in every state. Retrieved April 20, 2020, from https://www.usatoday.com/story/money/2019/02/05/gas-tax-state-what-costs-fill-up-your-car-across-country/38908491/
Minemyer, D. (2018, December 30). Why gas prices are so high in the Last Frontier. Retrieved April 19, 2020, from https://www.ktuu.com/content/news/Remembering-why-gas-prices-are-so-high-in-the-Last-Frontier-503690871.html
Bloomberg. (n.d.). Crude Oil & Natural Gas Prices. Retrieved April 13, 2020, from https://www.bloomberg.com/energy
U.S. Energy Information Administration. (n.d.). World Crude Oil Reserves by Year. Retrieved April 13, 2020, from https://www.indexmundi.com/energy/?product=oil&graph=reserves
Macrotrends. (n.d.). Crude Oil Prices – 70 Year Historical Chart. Retrieved April 13, 2020, from https://www.macrotrends.net/1369/crude-oil-price-history-chart
U.S. Energy Information Administration – EIA – Independent Statistics and Analysis. (2019, May 14). Retrieved April 20, 2020, from https://www.eia.gov/tools/faqs/faq.php?id=27&t=4
Farley, A. (2019, August 12). Understanding the Correlation of Oil and Currency. Retrieved April 20, 2020, from https://www.investopedia.com/articles/forex/092415/oil-currencies-understanding-their-correlation.asp
The most important trait for a Software Engineer
3 years
When you are dealing with other people in life, you need to treat them how you expect to be treated. Projecting a positive attitude will most of the time reflect it back at you. However, the world can present you challenges, and you have to handle them graciously, especially if you’re a team leader (Carpenter, Bauer, & Erdogan, 2010).
As a software engineer, you build the roadmap for other software developers to follow when constructing a software product. While a balanced combination of all five personality traits: Openness, Conscientiousness, Extraversion, Agreeableness, and Neuroticism is essential (2MinutePsychology, 2013), it is smart to adjust the dimension to suit based on the situation.
An essential personality trait as a software engineer would be openness. Being open with your team covers most of the spectrum. When you are engineering software, most of the time, you don’t have the complete picture instantly. On the one hand, this situation would require you to be open to receiving ideas, criticism, and suggestions. On the other hand, you will need to be transparent with your team about problems, evaluation, and cost (Iqbal, Aldaihani, Shah, 2019). Any software that does not establish this two-way route in openness will face many hurdles when dealing with his developers. While a software engineer might see the bigger picture, the developer sees the details and is the first in the line of offense (Iqbal, Aldaihani, Shah, 2019). Therefore, feedback from and to your developers is critical.
Openness can also streamline motivation, innovation, and trust. When you are honest, the team of developers wants to help you achieve the final goal because the benefits are clear on the table to everyone. Openness can also be a pillar for innovation, which is at the center of programming. The power of openness to achieve imagination and interest for your team can catalyze to produce the best product (Carpenter, Bauer, & Erdogan, 2010).
A smart team leader generally or a software engineer specifically can be at the center of innovation for their firm (Iqbal, Aldaihani, Shah, 2019). Through a routine practice of openness, the daily tasks at hand can make the workplace an enjoyable and pleasant bond based on trust and mutual respect.
Reference
Carpenter, M., Bauer, T., & Erdogan, B. (2010). Management Principles, v. 1.1. https://2012books.lardbucket.org/books/management-principles-v1.1/index.html.
2MinutePsychology. (2013, September 16). The big five personality model [Video]. YouTube.
Waude, A. (2017, May 8). Five-Factor Model Of Personality. Retrieved April 19, 2020, from https://www.psychologistworld.com/personality/five-factor-model-big-five-personality#references
Iqbal, A., Aldaihani, A., Shah, A. (2019, October 12) International Journal of Innovative Technology and Exploring Engineering ISSN: 2278-3075, Volume-8 Issue-(IJITEE) Retrieved April 19, 2020, from https://www.ijitee.org/wp-content/uploads/papers/v8i12/J97550881019.pdf
The Greek Poleis
0Archaic Greece was the period that witnessed the rise of the polis states. Archaic Greece thrived during the era around 800-480 BC (Brand, n.d.). The founding of these city-states was a breakthrough for human civilization. A study of all the occurrences of the word polis in the Archaic and Classical sources showed that there are some 11,000 which shows the importance and relevance of this new way of life (Hansen, 2006). This period brought people into a well-structured community and away from poverty living in small rural villages as nomadic groups.
A new form of Government: During Greek dark ages people lived scattered in small farming villages (History.com Editors, 2010). The Archaic period brought two revolutionary forms of government, the Oligarchy in Sparta and the Democracy in Athens. Sparta was predominantly an Oligarchy where the military men in a democratic vote appointed the Ephors to supervise the kings and legislative branch of the government. Sparta had a complicated form of government that consisted of predominantly Oligarchy, Democracy, Monarchy and Tyranny (Hornblower, 2019).
On the other hand, Athenian democracy was separated into three parts: The Assembly, The Council, and The Courts. Athens was the first city-state to have a proper and effective form of democracy. It was very straight forward, mostly every Athenian citizen had a vote, the majority ruled (Brand, n.d.). There was abuse by wealthy aristocrats and noblemen but Athenian democracy was far from perfect with characteristics like slavery, gender bias, and control by rich aristocrats.
Community-based life: The community became more important than any individual. The loyalty to a polis central government was cherished as a central value of life. The new world they lived in within the city-state was regarded as a form of life-improving factor. In Sparta it is evident with practices like the Syssitia where Spartan men were eligible to join exclusive dining, men competed ferociously to get into a group (Brand, n.d.).
The people make up the polis: In contradiction with any prior civilization in Archaic Greece, the people were more important than temples, structures, and stones. People were the essence of the existence of the polis. This is evident during the evacuation of Athens “Themistocles organized the naval resistance and the evacuation of the city of Athens itself” (Brand, n.d.) it showed that Athens itself was not important as a polis that can be rebuilt but rather the people that lived in it.
Economic powerhouse: The polis city-state was an economic powerhouse promoting a marketplace for trade and agriculture (Hansen, 2006). The olive oil and pottery industries were booming and served as an export market to pay for the large amounts of grain that were used to feed the Athenian growing population (Brand, n.d.). Democratic Athens attracted immigrants that enriched the city intellectually and in trade. “They worked as merchants, craftsmen and in other lucrative trades such as philosophers who served as private tutors to the sons of wealthy Athenians” (Brand, n.d.).
In conclusion, Greece during the Archaic period did not always have the same shape and size polis. Poleis changed over time in shape, size, and location. Governance was also another aspect that had a progressive momentum at times and a controlled Monarchy in others (Brand, n.d.). Wars internally among Greeks and with external powers like the Persians were certainly the most important factor that shaped the change in the structure and governance of the city-state.
Reference:
Brand, P. J. (n.d.). Athens & Sparta: Democracy vs. Dictatorship [PDF].
History.com Editors. (2010, March 05). Ancient Greece. Retrieved June 23, 2019, from https://www.history.com/topics/ancient-history/ancient-greece
Hornblower, S. (2019, June 20). Ancient Greek civilization. Retrieved June 23, 2019, from https://www.britannica.com/place/ancient-Greece
Hansen, M. H. (2006). Polis: An introduction to the ancient Greek city-state. Retrieved from https://ebookcentral.proquest.com
Searching through all columns in datagridview
013 years
by Ray Tawil
in Visual Basic.Net
Assuming you are searching for the name John, the following procedure will search all existing columns regardless
Dim x As Integer = 0
While x < DataGridView1.Rows.Count
Dim y As Integer = 0
While y < DataGridView1.Rows(x).Cells.Count
Dim c As DataGridViewCell = DataGridView1.Rows(x).Cells(y)
If Not c.Value Is DBNull.Value Or Nothing Then
If CType(c.Value, String) = "John" Then
MessageBox.Show("Found!")
End If
End If
System.Math.Min(System.Threading.Interlocked.Increment(y), y - 1)
End While
System.Math.Min(System.Threading.Interlocked.Increment(x), x - 1)
End While
MessageBox.Show("Search complete!")
End SubFiltering a datagridview
013 years
by Ray Tawil
in Visual Basic.Net
assuming you have a datagridview that has data in it.
you want to avoid recalling sql from the database & just want to filter the datagrid.
you can do the following, What you need (1 datagridview (data), 1 button (search), 1 textbox (string to search), 1 variable to precise the criteria your searching for)
Dim findcrit as string
Dim dt As DataTable = Ds_Pos.Employees
Dim dv As New DataView(dt)
Dim _RowFilter As String = ""
Dim _FieldType = dt.Columns(findcrit).DataType.ToString
Select Case _FieldType
Case "System.Int32"
_RowFilter = "convert(" & findcrit & ", 'System.String') like '" & Me.TextBox1.Text & "'"
Case "System.Int64"
_RowFilter = "convert(" & findcrit & ", 'System.String') like '" & Me.TextBox1.Text & "'"
Case "System.Double"
_RowFilter = "convert(" & findcrit & ", 'System.String') like '" & Me.TextBox1.Text & "'"
Case "System.String"
_RowFilter = findcrit & " like '" & TextBox1.Text & "*'"
End Select
dv.RowFilter = _RowFilter
EmployeesDataGridView.DataSource = dvThe cases are to cast the type of variable from any type to string because you can only use the method on string data types.
the idea is to move the content to a data table then filter then return it back to the datatable.
using c# and vb in the same web project
013 years
Can you have both c# and visual basic in the same web site project?
Definitely! It simply wouldn’t make sense from a new project standpoint, code reviews, coding standards, continuity, project maintenance, etc.
however, people still want it. to-date i never really tried (and that’s been my answer). I was presented with a usable scenario of why you may need (not want, need) to do this, so I finally tried it. the answer: yes…kinda…sometimes.
let’s assume we have a web site structure like this:
we have the App_Code folder and a .cs and a .vb file in the same projects (separated into sub-folders). note that the project sees them as folders (yellow folder icon) in the special folder. each class within there basically has a “hello world” function only, like this in the c# file:
public string SayHelloCS()
{
return "Hello from CS";
}and the visual basic file has a similar function emitting "Hello from VB."
now, if you run default.aspx in this structure, this is what you will see:
The files ‘/WebSite5/App_Code/VBCode/Class2.vb’ and ‘/WebSite5/App_Code/CSCode/Class1.cs’ use a different language, which is not allowed since they need to be compiled together.
interesting? probably not, but it makes sense…so how do we overcome. we use a configuration option called codeSubDirectories. here’s what we need to add to our <compilation> node in our web.config:
<compilation debug="false">
<codeSubDirectories>
<add directoryName="VBCode"/>
<add directoryName="CSCode"/>
</codeSubDirectories>
</compilation>once we add those codeSubDirectory nodes, let’s “look” at what the project structure looks like now:
as you can see the code folders are now “special” in the eyes of visual studio. now if we browse default.aspx we will see:
Hello world from CS. Hello world from VBCustom error pages using .htaccess
0We’ve all seen the dreaded Error 404 message – the result of broken links and mistyped URLs. You’ve probably been on some websites where the error pages are customised with their own logo and message, and I’m sure you’ll agree that it looks far more professional than the standard one.
In this article we’ll show you how to use Apache’s .htaccess file to make your own customised error 404 pages.
Create a new text file on your computer, and call it “htaccess.txt”. Enter the following lines:
<Files .htaccess>
order allow,deny
deny from all
</Files>
Now you need to create the 404 page. Make a new web page called “error404.htm” and enter “This is my 404 page”. Enter it a few dozen times, as Internet Explorer won’t display it unless the file is over 512 bytes.
Once it’s done, login to your webspace with your FTP client, and create a new folder called “errordocs”. Upload the file “error404.htm” to this directory. Upload “htaccess.txt” to the root of your webspace and rename it to “.htaccess” — there’s no .txt at the end, no name in front, just “.htaccess”. If the file seems to vanish don’t worry, some FTP clients don’t display it — the file’s still there.
ErrorDocument 404 /errordocs/error404.htm
The first part stops people viewing your .htaccess file. The second part tells Apache to redirect any 404 errors to the file “error404.htm”.
How to mass delete comments in WordPress
0METHOD 1:
To mass delete comments in the WordPress admin panel, follow these steps:
Log in to the WordPress admin panel and go to the “Comments” section.
On the comments page, you will see a list of all the comments on your site. You can select multiple comments by clicking the checkbox next to each comment you want to delete.
Once you have selected the comments you want to delete, scroll to the top or bottom of the comments list and look for the “Bulk Actions” dropdown menu.
Select “Move to Trash” from the dropdown menu. This will delete the selected comments from the site.
To permanently delete the comments, go to the trash section and select the comments you want to delete permanently and click on “Empty trash” or you can also select all the comments and delete it once.
Note that deleting comments permanently will remove them from the site permanently and it will not be recoverable.
Additionally, in case you have thousands of comments and you want to delete all of them, you can use a plugin such as “Delete All Comments” or “Bulk Delete” to delete comments in bulk. These plugins will enable you to select and delete comments based on different criteria, such as date, author, and more.
WordPress also has an inbuilt feature to approve, unapprove, mark as spam, move to trash and delete comments in bulk. It can be found by clicking on the checkbox on the top of the comment list, which will give you option to perform bulk actions on selected comments.
It’s always a good practice to take a backup of your website before making any major changes.
METHOD 2:
You can also go to plugins -> Add new plugin and search the WP Bulk Delete plugin and use that to delete more than the allowed page comments at once.