If FAA is relaxing rules to allow passengers to use 802.11b transmitter while flying, there are some possibilities to get cellphones approved for flights as well. I hate when flight attendants ask you to shut down your cellphone upon departure...
The reason why initial VoIP business was founded for international long distance was due to the monopolistic pricing of international voice calls. Do you remember what international phone calls used to cost 5 years ago? Data connections were not subject to same regulations as voice traffic thus there was a rapid explosion of companies selling international VoIP calls. The sound quality was awful, lot of echo and latency. Eventually sound quality got better but by that time competition and deregulation dropped the prices and many VoIP companies went bankrupt.
While voice is data not all data is equal. Voice is sensitive to latency, jitter and dropped packets. FTP traffic, however, is not.
Symbol has made WLAN phones over a year ago. I don't see the point, though. WLAN technology is great for bursty data connections such as web surfing, but providing QoS over WLAN connections is a challenge. Many access point support PCF (Point Coordination Function) but providing end-to-end QoS is a different story over public IP networks. In an enterprise LAN network this may work in small scale but if you have thousands of phones such as in a busy downtown center and try to maintain decent sound quality I bet you are in trouble.
Check this test by ExtremeTech. They had difficulties getting 4 uncompressed audiostreams over 802.11b segment. With compression this could improve by factor of 10x but without PCF bandwidth would not be evenly distributed.
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If FAA is relaxing rules to allow passengers to use 802.11b transmitter while flying, there are some possibilities to get cellphones approved for flights as well. I hate when flight attendants ask you to shut down your cellphone upon departure...
Beginning in 2004, the service will cost between 30 (US$32) and 35 per flight. Not bad compared to for example what T-mobile charges at the airports.
The reason why initial VoIP business was founded for international long distance was due to the monopolistic pricing of international voice calls. Do you remember what international phone calls used to cost 5 years ago? Data connections were not subject to same regulations as voice traffic thus there was a rapid explosion of companies selling international VoIP calls. The sound quality was awful, lot of echo and latency. Eventually sound quality got better but by that time competition and deregulation dropped the prices and many VoIP companies went bankrupt.
While voice is data not all data is equal. Voice is sensitive to latency, jitter and dropped packets. FTP traffic, however, is not.
Symbol has made WLAN phones over a year ago. I don't see the point, though. WLAN technology is great for bursty data connections such as web surfing, but providing QoS over WLAN connections is a challenge. Many access point support PCF (Point Coordination Function) but providing end-to-end QoS is a different story over public IP networks. In an enterprise LAN network this may work in small scale but if you have thousands of phones such as in a busy downtown center and try to maintain decent sound quality I bet you are in trouble.
Check this test by ExtremeTech. They had difficulties getting 4 uncompressed audiostreams over 802.11b segment. With compression this could improve by factor of 10x but without PCF bandwidth would not be evenly distributed.