Thursday, April 25, 2019

How to prevent VOIP Spam

What is SPIT?

Spam over Internet Telephony (SPIT) is telephone spam that is transmitted over the Internet Protocol using IP (Voice over IP) telephony. Telephone spam refers to unwanted telephone calls that are automatically and in large numbers recorded. Phone spam is similar to email spam, but is currently less common and requires other safeguards due to synchronous communication.

How abuse takes place

IP telephony, as well as email and other Internet applications, is prone to being abused by unwanted messages and connections. Call machines can be used for telesales, telemarketers, for alleged winning messages, or as phone calls. In particular, IP telephony offers this freely available software (such as Asterisk or SIP) and inexpensive options to automatically sell a large number of calls. The IP telephony is often based on the Session Initiation Protocol (SIP) [1] for setting up, controlling and reducing the telephone connections. After establishing a SIP session and accepting the call by the called party, a pre-recorded spam message can be recorded. For pure lock or ping calls, no audio data is transmitted.

Large numbers of unwanted and automated phone calls

SPIT is characterized by a large number of unwanted and automated phone calls that are transmitted using the Internet Protocol. The caller (spammer) tries to establish a large number of connections using suitable software and plays a recorded message as soon as the called party answers the call. Using the widely used Session Initiation Protocol (SIP), the connections to INVITE messages are initiated and then configured and set up with other messages; The audio data is then transmitted via the Real-time Transport Protocol (RTP). The spammer can this telephony software such. B. Asterisk use. The spam calls can be transmitted via gateways of the telecommunications network operators in the conventional telephone network (PSTN).

How to prevent VOIP Spam?

Many users have no problem with SPIT already being "shielded" behind NAT or a package filter, AKA firewall. Others, running a Linux server with VOIP server and client on it might be exposed to VOIP Spam. These can protect themselves by setting up one package filter rule:

iptables -A INPUT -p udp ! -s 217.10.79/24 --destination-port 5060 -j REJECT
assuming 217.10/16 is the IP range from your ISP. In this case it's Sipgate. That will throw away all UDP packages to the SIP port (5060, might differ on other setups) unless they come from 217.10.79/24.

Tuesday, April 9, 2019

How to disable auto play of videos in Chrome and Firefox browsers

When users enter certain web pages, often videos embedded there start to play automatically. Many users, including me, do not wish to run videos they didn't demand. But they play anyway. Is there a way in Browsers like Chrome or Mozilla's Firefox to deactivate the automatic play of videos? Besides it's annoying, these videos use data. When a user has a "cap" with his ISP (the maximal amount of data he can transfer every month) he might pay additional charges for a data transfer, he didn't demand. Luckily for web browser like Mozilla's Firefox and Google's Chrome there is a way, to deactivate the automatic playing of videos, like in Youtube.

Chrome and Chromium web browsers

The Chrome web browser is currently the dominant browser and holds the biggest market share. Thanks to the implementation in Android smart phones and tablets, Android ships.

Desktop

After launching the browser click into the address bar on top and type in about: flags and hit the RETURN key. On top you find a search form. Enter autoplay and click on the first find the drop down menu and choose Document user activation is required. After you restart Chrome videos should not start automatically anymore, but asks the user to confirm, he wants to run a particular video.

Chrome on Android

This is easier. Launch the Chrome browser on your tablet or smart phone and visit Settings and then Site Settings. Scroll down the media menu and select the media tab. There you must select autoplay and click the checkbox, to disable the function.

Mozilla's Firefox

The Firefox browser of Mozilla has some great features. It is highly customizable. It has among other native features the ability, to prevent videos from starting to play automatically. Click the URL bar and type in about:config. Ignore the warning and use the search form to find media.autoplay.default. Set this to "1" if it was not already set. Also find media.autoplay.allow-muted and set this to false. Restart the Firefox browser that the changes take effect

Other methods

If this isn't working for you, third party add-ons come into play. Open the Preferences menu and search for addons or extensions. There is a search form. Search for something like disable, auto play or automatic and install the appropriate extension.

Wednesday, March 27, 2019

TV series The Orville

The series The Orville is an American TV show created by Seth MacFarlane and premiered on September 10th 2017 on the Fox network in the United States and simultaneously on the Citytv2 network in Canada.

It's a science-fiction drama set in a future, where Earth is part of a larger community of civilizations that coexist in the universe in a peaceful way. The story takes place around a medium-class space ship called Orville and its crew.

Plot

In the 25th century, Earth is part of the Planetary Union with an extended civilization, advanced and above all peaceful and comprises a fleet of approximately 3000 vessels. Among them the Orville, a modern spacecraft led by Captain Ed Mercer (portrait by Seth MacFarlane, the producer of the show), determined to prove his worthiness and to write a new chapter in his life, backed by an eccentric crew.

Cast

Main actors

  • Seth MacFarlane as Captain Ed Mercer
  • Adrianne Palicki as Commander Kelly Grayson
  • Penny Johnson Jerald as Dr. Claire Finn
  • Scott Grimes as Lieutenant Gordon Malloy. Scott Grimes was acknowledged in the movie Critters, when he was at the age of fifteen.

Continuity

The first season is considered by fans to be lighthearted, with the focus on jokes similar to these found in Family Guy, which is also produced by Seth MacFarlane. Season two started much darker and had fewer jokes but more blood and killings. Later episodes of season two followed what season one was like.

Crossover between Family Guy and The Orville

Some episodes of Family Guy mentioned The Orville. Many fans of both shows expect that at some point in the near future a crossover between Family Guy and The Orville should take place.



Star Trek references

Some actors from the Star Trek franchise took part in The Orville. Jonathan Frakes and Robert Duncan McNeill already directed episodes of The Orville. While actors like Roberto Picardo (the EMH of Voyager) or John Billingsley, portraying Dr. Phlox in Enterprise or Tim Russ (playing a Vulcan officer onboard the USS Voyager) already had a role in The Orville. Apparently Seth MacFarlane likes to have actors from the Star Trek universe in his show.

Thursday, February 28, 2019

War between India and Pakistan

India's Prime Minister Narendra Modi hoped to come out of the election campaign as a strong man. He did not quite succeed. On February 26th 2019 Modi bombed a terrorist camp in Pakistan's Khyber-Pakhtunkhwa province, directly adjacent to the Kashmir mountainous region. He said he responded to a terrorist attack in Kashmir. In the long history of skirmishes between the two countries holding a nuclear stockpile, it was the first time that India did this, thus starting the conflict to escalate.

The cold war between Indian and Pakistan got hotter

Pakistan was unwilling to follow New Delhi's contention that the bombing was an anti-terrorist operation and a non-military preemptive strike. The following day Pakistani military aircraft shot down an Indian fighter plane over Kashmir and took the pilot in captivity. Now the airspace over Pakistan is closed to civilian traffic, because the government expects attacks from India. Thousands of flights have to be diverted worldwide. If this escalates to a war between the two nuclear powers, would it not only have consequences for the South Asian region but the rest of the world.

Dangerous situation

The situation is extremely tense. For the first time in almost 50 years, the air forces of both countries are in direct confrontation. The last war between India and Pakistan took place in 1971 and ended with the defeat of Pakistan and the secession of the state of Bangladesh, formerly East Pakistan.

My opinion

If Narendra Modi wants to respond to a terrorist attack and bomb a camp he should had spoken to the Pakistani president before. Let the Pakistani handle it. Only if Pakistan declined Narendra Modi should tell the Pakistani India will take care of of the situation itself. But as history often shows failure to communicate often leads to disaster. I wonder if Narendra Modi hasn't the brains to not have seen this. Lets pray that if the wage nuclear war there are no strong winds that the fallout falls on their countries only. Both have quite a large landmass.

Tuesday, February 19, 2019

The Crucible by Arthur Miller

Synopsis

It is 1692 and a town in Massachusetts has an unnerving undercurrent running through it which threatens to tear apart the peace and harmony on which is it based. The undercurrent is that witchcraft is being practiced within the town and with everyone pointing the finger and suspicions at everyone else, the waters are cloudy as to who is actually guilty of the crime. The Salem witch trails start and suddenly everyone's dirty washing is being aired in public.

Strong Characters

The characters involved have been brought to life by Miller to the point that they can be seen on a daily life. Giles Corey is one such example. He is an ageing man, yet one of strong principles and also of integrity although very traditional in nature. He finds it strange and beyond him that his wife reads books, a point that he airs. This then results in his wife being accused of witchcraft. He remains strong to the end in a scene that is quite emotional. Stones are piled onto his chest in a bid for him to confess to practicing witchcraft - if he confesses, he will live but his family cannot inherit his land if so. His reply is constantly "more weight".

A great play with many twists, highlighting the evil trappings of life such and jealously and revenge and showing how a small event can spiral out of control. You cannot say you are a fan of modern plays unless you have seen this! Essential viewing.

Monday, January 21, 2019

How to silence a smoke detector

Smoke detectorWhen your smoke detector starts chirping at you it wants to tell you to replace the empty 9 Volt block battery with a fresh one. Because this chirping becomes very annoying and more frequent the longer you wait you should act soon and put a new battery in place. To replace the empty pile you need a ladder or other means to reach the detector. Some allow to unscrew the top of the body with the hand, for others you might need a screwdriver to insert into a gap near the latch then pull the screwdriver and the top pops off. Remove the old battery and replace it with a fresh one. Assemble the body again.

Connected or not connected to the grid, that is the question

With a new power source detectors now connected to the grid shall run at least six month, so you should replace it twice a year. As a reminder many people use the dates we go from standard time to daylight savings and back. Items connected to the grid also use a pile as backup in case a fire knocked out electricity. These piles hold up to five years.



Temporarily silencing a chirping smoke detector

If you don't have a 9 Volt block cell handy or cannot reach the detector chirping can make you mad. But many smoke detectors ran into allow to silence them temporary for up to ten hours. Locate the small button facing downwards. You need some item to reach it. A long soup ladle might do the job. Press the button for about a half second. It will beep like when it had detected smoke then be silent. Have a look at that button which now should slowly flash all few seconds. Then you are good for eight to ten hours of tranquility and can finally have a good night sleep without the annoying noises. But sometimes it starts becoming noisy again after a few minutes. So wait say 30 minutes before you actually can be sure it will be silent. If not push the button for another half second again. But keep in mind this helps only temporarily. Go ahead and install a new pile instead. That way you mute the alarm device and can go back to your normal life.

Monday, December 31, 2018

The golden age of arcade video games

The golden age of arcade games is an era in which the popularity and innovations of arcade video games were at their peak. This period started 1978 with the release of Space Invaders until the mid-1990s with the development of personal gaming equipment becoming more powerful than typical arcade games.

Abstract

By the early 1980s, video game technology had become sophisticated enough to offer good quality graphics and sound, but still remained basically simple. Realistic images and full-screen animations were not yet possible, and only few games used synthesized voices. The success of a game based mainly on gameplay and the fun it provides . This interest in gameplay is the reason why many of these games continue to be enjoyed today despite being outdated by today's standards.

Economic sector

The Golden Age was a moment of great technical and conceptual creativity for arcade video games. The games were developed around a wide variety of genres while designers had to grapple with the strict limits of CPU power and available memory. This period also saw the emergence of arcades, places dedicated exclusively to arcade gaming. At this time, arcade bells are beginning to appear in supermarkets, gas stations, pizza parlors and many other retail businesses eager to generate additional revenue. Popular games then caused especially teenagers to scramble to try out the latest video game attraction.

Companies

The most successful companies in this field are probably Atari, particularly in the United States and Namco, particularly in Japan. Other publishers include Bally Midway, Capcom, Cinematronics, Konami, Nintendo, Sega, SNK, Taito and Williams.

Successful games of this golden era

The games below are some of the most popular and influential games of the period. All are in the Top 100 video arcade games according to KLOV.

  • Space Invaders (1978)
  • Asteroids (1979)
  • Galaxian (1979)
  • Lunar Lander (1979)
  • Battlezone (1980)
  • Berzerk (1980)
  • Centipede (1980)
  • Defender (1980)
  • Missile Command (1980)
  • Pac-Man (1980)
  • Star Castle (1980)
  • Warlords (1980)
  • Wizard of Wor (1980)
  • Donkey Kong (1981)
  • Frogger (1981)
  • Galaga (1981)
  • Ms. Pac Man (1981)
  • Qix (1981)
  • Tempest (1981)
  • Amidar (1982)
  • Vanguard (1981)
  • Burgertime (1982)
  • Dig Dug (1982)
  • Joust (1982)
  • Moon Patrol (1982)
  • Pole Position (1982)
  • Q*bert (1982)
  • Robotron 2084 (1982)
  • Time Pilot (1982)
  • Tron (1982)
  • Xevious (1982)
  • Zaxxon (1982)
  • Dragon's Lair (1983)
  • Elevator Action (1983)
  • Spy Hunter (1983)
  • Star Wars (1983)
  • Tapper (1983)