Cisco Technology, Inc.

Sandeep Singh Kohli

Parameswaran Kumarasamy

Kavithadevi Parameswaran

Michael Edric Tasker

Vinay Jayant Pande

Vijay Arumugam Kannan

Hosahalli Nanjappa Narendra

Prasad Miriyala

Paul Edwin Jones

Jayesh Chokshi

Sabita Jasty

Paul R P Chu

Soumya Kumar Kalahasti

Sunila R Ainapure

In a particular embodiment, a network device receives, from a first device, a first call request for a second device. The network device may then send the first call request to a redirect server, which can determine where to send the call. The network device receives a response from the redirect server indicating an address to redirect the call request to. The network device then determines a redirect ID for the redirect. The network device sends a message to the first device with the redirect ID where the message indicates that a redirection occurred to the third device. The network device then receives a second call request from the first device that includes the redirect ID. The network device determines if the call was part of a previous redirect. If so, the second call request is sent to the address associated with the redirect ID.

Handling redirect calls

We describe a system embodiment comprising generating a Secure Real-Time Transport Protocol (SRTP) encapsulated packet and including a secure media indicator into the SRTP encapsulated packet. The method further comprises inserting the SRTP encapsulated packet into an SRTP voice stream associated with an active call between a source and a destination endpoint and indicating an end-to-end secure call between the source and destination endpoints responsive to the secure media indicator. And we describe a method embodiment comprising transmitting a request message from a source endpoint to a destination endpoint participating in an active call and setting a secure media flag in the request message at each node in a signaling path associated with the active call. The method further comprises returning a response message from the destination endpoint to the source endpoint responsive to the request and indicating an end-to-end secure call between the two endpoints.

Identify a secure end-to-end voice call

A method for interworking supplementary call services between different VOIP protocols is provided. The method comprises receiving, during a call between a first end device and a second end device, a first message in a first protocol format for the second end device to transfer the call to a third end device; determining interworking information to interwork the first message to a second message in a second protocol format; generating the second message based on the interworking information, such that the second message initiates the call transfer to the third end device.

Interworking supplementary call services between different communication protocols

In one embodiment, interworking procedures between H.323 and SIP ensure that in-band tones and announcements, along with local and remote ringback, are properly played or generated.

Properly playing in-band tones before call establishment when performing protocol interworking

In one particular embodiment, the secure media includes information sent using secure real-time transfer protocol (sRTP). Supplementary services may include call transfers, forwards/redirects, call hold with music on hold (MOH), call hold with no MoH, call resume, call park, call pickup, call blast etc. In a call flow, a call request may be received from a first device for a second device. The call request may include at least one set of keys and be ready for establishment of an sRTP call. It is then determined that a supplementary service is needed for the call request. For example, a supplementary service may indicate that a call redirect to a third device is required. The gateway then facilitates a supplementary service call with the third device. This is facilitated without contacting the first device to generate a second key after receiving the initial call request.

Supplementary services using secure media

Growing community of inventors

Fremont, CA, United States of America

Sandeep Singh Kohli