Vomit (spelled all lower-case) is a Unix software utility that takes IP telephony packets captured by another Unix tool, tcpdump, and reassembles them into a Wave file that can be listened to over a computer's speakers. Although vomit can be used for network debugging or as a speaker-phone utility, it is most often associated with VoIP eavesdropping attacks.
"Vomit" is an acronym for Voice Over Misconfigured Internet Telephones. The name is somewhat misleading. The telephones are not actually misconfigured; they are simply using the same data stream as the network's computers. To ensure that data network users cannot snoop on IP telephony calls by using a program like vomit, it is recommended that network administrators always separate voice and data networks by running them on different virtual LANs (VLANs).