Different TimeZones

Different TimeZones:

Due to the rotation of the earth, different parts of the earth receive different amounts of sunlight causing morning, evening, and night. Now, if we had one time zone, then 12 pm would be noon in some places, but it would be night or evening in other places which would be inconvenient. Therefore, the scientists made different time zones according to the earth’s rotation with respect to the sun. Since the earth rotates 360° in 24 hours this means in one hour the earth moves by 15°. Thus, we divide the planet into 24 sections or time zones. Each section or region was about 15 degrees wide and had a specific standard time. This helped us know the proper time of the day in that part of the world....

Daylight Saving Time (DST):

Daylight Saving Time (DST) is the practice of turning the clock ahead as warmer weather approaches so that darkness falls at a later time and moves back as it becomes colder again. Toward the end of March countries in the Northern Hemisphere set their clocks ahead by one hour to push sunsets later in the evenings and sunrises later in the morning. Then, in late October, they are wound back by an hour, subtracting an hour of daylight from the evening and making the early mornings brighter. While in the Southern Hemisphere, the reverse occurs, with daylight saving time taking place during the summers. DST is practiced to better use daylight by extending the amount of time we can spend outside during daylight hours....

Wireshark and Time Zones:

If we frequently travel across different time zones then it becomes quite confusing if we get a capture file from a different time zone. But we do not need to worry about the timezone as we are only interested in the time differences between the packet time stamps. The packets in the capture file format like libpcap, Windows Sniffer, *Peek, Sun snoop formats, and newer versions of the Microsoft Network Monitor and Network Instruments/Viavi Observer have arrival time as UTC values. Also, UNIX and Windows NT-based systems use time internally as UTC values....

Time Zone Examples for UTC Arrival Times:

Component Los Angeles New York  London India  Tokyo Capture File (UTC) 10:00 10:00 10:00 10:00 10:00 Local Offset to UTC -8 -5 0 +5:30 +9 Displayed Time (Local Time) 02:00  05:00 10:00 15:30 19:00...