Asterisk-Java

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License: gpl

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License: AFL1-1, gpl

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License: mozilla_public_1_1

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License: gpl

Yate   (Compare Project)

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Adhearsion   (Compare Project)

Mostly written in Ruby

License: mit

Wazo   (Compare Project)

Mostly written in Python

License: gnu3

Gemeinschaft (by Amooma), later known as GS3   (Compare Project)

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License: gpl

XiVO Solutions   (Compare Project)

Mostly written in Scala

License: gpl3, lgplv3

baresip   (Compare Project)

Mostly written in C

License: BSD-3-Clause