ISP Information:
A "virtual" network constructed by connecting computers together over the Internet and encrypting their communications so that other people cannot understand the communications. The benefit is that people can connect to a local LAN from anywhere on the Internet. This allows easier connectivity and lower phone bills for travelling salespeople. They just sign up with a national ISP and call local POPs from their hotels as
ISP Glossary:
Virtual Private Network - nyukfah@pd.jaring.my (nyuk fah) writes: My current internet connection is private ip and behind a firewall. Thus I wonder any solution VOIP over HTTP? Which I can solve the private IP and firewall limitation?No, not over HTTP, at least if you want decent quality VoIP, sinceHTTP uses TCP as it's transport. TCP guarantees a complete andin-order data stream, and does this by stopping the flow of data to anapplication under it gets missing packets resent by not acknowledgingthem to the sender. Thus, a couple of missing packets could easilycause at least several seconds of no audio, even though the missingpackets may only make up a fraction of a second of loss.VoIP usually uses UDP for the audio connection, with H.323 or SIPcontrolling it. Many firewalls have provisions to be configured toproperly NAT H.323, or you could use a gatekeeper routed setup forH.323. SIP has provisions for proxy servers and NAT inside theprotocol.You probably want to check your firewall's documentation and see if itsupports firewalling/NAT'ing H.323.Bob
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