• Create BookmarkCreate Bookmark
  • Create Note or TagCreate Note or Tag
  • PrintPrint

17.1. Latency

Network latency is the time it takes for a packet of information to travel across a network (or networks) from sender to receiver. On a high-speed local network, it may take only a millisecond (ms; one-thousandth of a second) for a single packet of information to travel from sender to receiver. An organization with network nodes spread over a few kilometers and a high-speed backbone should still provide latency of less than 10 ms. Organizations with a high-speed connection into an Internet service provider (ISP) may achieve latencies of 15 to 50 ms when reaching well-connected national sites, as well as some international sites. On the other hand, home users will often experience latencies in the 40 ms to 500 ms range when accessing the same sites on the Internet. Network congestion can increase latency dramatically. The routers in a congested network will drop packets they cannot handle. FlashCom uses the TCP protocol, which automatically resends dropped packets. If packets are repeatedly dropped and resent, latency can increase dramatically.

While everyone who has ever used the Internet has experienced network latency, the delay in delivering packets across the Internet is not the only cause of slow response times. A busy FlashCom application instance will queue remote method calls and deal with them one at a time. If there is a long delay between the time someone sends a message in a text chat and the time it takes her message to appear in the chat message area, it may be because of a slow network connection, a busy application instance, or both.


PREVIEW

                                                                          

Not a subscriber?

Start A Free Trial


  
  • Creative Edge
  • Create BookmarkCreate Bookmark
  • Create Note or TagCreate Note or Tag
  • PrintPrint