Abstract: To enable internet softphone users to join to calls hosted at an audio conferencing bridge, a SIP Invite may be received at a bridge interface layer of an audio conferencing system. Parameters of the SIP Invite may be extracted, e.g. from one or more X-header fields and processed to enable the internet softphone to be joined to an audio conferencing bridge. The bridge interface layer may receive a SIP Refer message from the audio conferencing bridge that indicates a second audio conferencing bridge external to the system. The bridge interface layer may forward the SIP Invite to the second audio conferencing bridge and the RTP media may be established through the session border controller (SBC) of the audio conferencing system.

Abstract: To enable load balancing and the like for audio conferencing systems of an audio conferencing network, a DNS server may receive a DNS lookup from an internet softphone and return a prioritized list of audio conferencing system identities. The internet softphone may select an audio conferencing system and forward a SIP Invite to a Bridge interface layer of the respective audio conferencing system. If the SIP Invite does not generate a successful connection or generates a timeout, the internet softphone forwards the SIP Invite to the next prioritized Bridge interface layer in the list.

Abstract: To enable load balancing and the like for audio conferencing systems of an audio conferencing network, a DNS server may receive a DNS lookup from an internet softphone and return a prioritized list of audio conferencing system identities. The internet softphone may select an audio conferencing system and forward a SIP Invite to a Bridge interface layer of the respective audio conferencing system. If the SIP Invite does not generate a successful connection or generates a timeout, the internet softphone forwards the SIP Invite to the next prioritized Bridge interface layer in the list.

Abstract: To enable internet softphone users to join to calls hosted at an audio conferencing bridge, a SIP Invite may be received at a bridge interface layer of an audio conferencing system. Parameters of the SIP Invite may be extracted, e.g. from one or more X-header fields and processed to enable the internet softphone to be joined to an audio conferencing bridge. The bridge interface layer may receive a SIP Refer message from the audio conferencing bridge that indicates a second audio conferencing bridge external to the system. The bridge interface layer may forward the SIP Invite to the second audio conferencing bridge and the RTP media may be established through the session border controller (SBC) of the audio conferencing system.