Internet Insight: Getting Data Up and Down
Compared with terrestrial communications, satellite links can be tricky to manage.Compared with terrestrial communications, satellite links can be tricky to manage. For instance, satellite service providers must deal with the weather. Heavy rain or snow can slow transmissions and increase the number of dropped packets. Fortunately, new algorithms can minimize weather problems. Another problem is distance. A signal travels from a users desktop to a network switch to a very small aperture terminala satellite dishthat exchanges information with a satellite orbiting the planet 22,300 miles up. Each time a data packet is shipped, it travels from the sending system to the satellite and then down to a receiving dish.
The minimum time to make the trip is 0.25 seconds. However, the framing, queuing and switching that TCP/IP relies on to ensure that packets arrive at the proper destination can increase that time to as much as 0.5 seconds.