Free h.323 software for windows

Vulnerability in Microsoft Internet Security and Acceleration Server 2000 H.323 Filter Could Allow Remote Code Execution (816458) 1.0 is created to allow an attacker to overflow a buffer in the Microsoft Firewall Service in Microsoft Internet Security and Acceleration Server 2000. An attacker who successfully exploited this vulnerability could try to run code of their choice in the security context of the Microsoft Firewall Service. This would give the attacker complete control over the system.

The H.323 filter is enabled by default on servers running ISA Server 2000 computers that are installed in integrated or firewall mode.

Mitigating factors:

• ISA Servers running in cache mode are not vulnerable because the Microsoft Firewall Service is disabled by default
• Users can prevent the risk of attack by disabling the H.323 filter

PicoPhone is a simple Internet Phone, which allows multiple concurrent calls, has chat functionality, delay control, silence threshold control, works well with NAT routers.
I made it, because all the Internet phones around are quite heavy and use complicated protocols, such as H.323, which has problems with NAT routers. PicoPhone uses a simple UDP-based protocol, which works very well with NAT. The program accepts connections on UDP port 11676 and makes connection to that port.
Optionally a port number can follow the address (the colon is used as a separator), if the connection has to be made to another port (the NAT router on the receiving side should convert the port number to the default 11676).
PicoPhone allows multiple concurrent calls, but the audio device should allow multiple output streams to be opened simultaneously. Conferences are not set up automatically, i.e., if A calls B and C, B and C wont hear each other: B has to call C, or C has to call B for the complete conference to be set up.
On incoming calls the program plays the file ringin.wav, which should be present in the default windows location for wav files or in the same directory of PicoPhone.
Operation
Enter a fully qualified domain name or an IP address and then press the Call key. You can put a comment before the address, but in this case you should enclose the address between < and >. If not specified, the address uses the standard PicoPhone port, 11676. A port can be specified after the address, using a colon as a separator. The syntax can be therefore:
address, or
address:port, or
name , or
name
When the second two forms are used, and also the first two forms, when the address is a DNS name and not an IP address, the address will be saved and it will be available from the drop down box for the next time.

JoinPhone Lite? JoinPhone Lite is a free S/W based on H.323 videophone standard from Digital Media Tech that lets you enable your PC and the Internet to hold face-to-face audio and video conversations with friends, family, and co-workers around the world. Its compatible with NetMeeting, CU-SeeMe Pro and has very good audio and video quality. Features do include A/V recording/playback, image capture, file transfer, chat, memo pad and etc. Especially JoinPhone Lite is quick and easy to install, setup and use! This is the best chance to you to feel about super real-time communication S/W ! Get it now without registration !

Support USB phone
PC to PC, PC to Phone, Phone to PC
H323 compliant
Touch-tones [DTMF]
Dial/ Redial/Hangup
Dynamic CODEC Selection
Caller ID
Call Timer
Backspace/Clear/Delete
Microphone & Speakers Levels
Last Caller-IDs
Recent Calls Dialed
Recent Calls Received
Sound Device Selection
New Familiar-looking Menu
Phonebook
Speed Dial
Benefits:
Easy to install
Intuitive user interface & Menu.
Easy to navigate and configure.
G.723/729/GSM codecs included
NAT/Firewall support
Multiple gatekeeper selection
Customised skin can be provided by Author

With iTALK2u make free PC to PC calls to and from anywhere in the world. (international too!), iTalk2u Communications offers free high quality phone calls over the Internet to other iTalk2u users.
The software and PC to PC calls are free as well as some other features:
Built in Instant Messaging
User online status (Real Time)
User profile and search
File Transfer
Free PC 2 PC Calls
Caller "On Hold"
No Firewall to Firewall setup
No Spyware or Adware
H.323
Web Click 2 Call
And Much More...
iTALK2u is quick and easy to install. Just download it, register, and within seconds you can plug in your PC headset and call your friends on iTALK2u. iTALK2u calls have the best sound quality and are the most secure with end-to-end encryption. Best of all, iTALK2u does not require you to reconfigure your firewall or router.