For people who are in VoIP business.

Here is the link
http://armkb.com/qnmodeler

Here is description

Purpose
When you need to explain a network topology to someone or understand someone's topology you may use this online tool to build and share diagram of topology.

Benefits

• No need to install any 3rd party software on your hard drive
• Completely free
• Can store and load diagrams from server
• Multi language support
• As small as

...

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