| Technology Innovation Gr., Mobile Handset R&D Center 1 3GPP2 – Call waiting CR Current Technology In CDMA 3GPP2 standards, when the user who is in conversation with another person, gets another call – he gets a call waiting indication This is delivered by a Layer 3 message called Flash with Information which gives the information of the third call (calling party number etc) The user has the ability to take the waiting call and swap calls between first call and waiting call

| Technology Innovation Gr., Mobile Handset R&D Center 2 3GPP2 – Call Waiting CR Problem Statement Below Use Case explores issues existing in the current implementation of CDMA2000 standards wrt Call waiting Scenario 1 When the MS C makes a call to MS A when MS A is in conversation with MS B, MS A gets the call waiting indication. When MS C disconnects the call before MS A can take the call, then there would be no signaling information from the network to MS A that MS C has disconnected the call. As a result, the MS A still shows the call waiting indication misleading the user that the call is still there. This issue exists due to the lack of a specific message in the standards to end a call waiting scenario. If the release order is send by the network, it ends both the call i.e. from MS B and MS C, since MS A is on only one traffic channel and release order indicates that the traffic channel has to be released Scenario 2 When the MS C makes a call to MS A when MS A is in conversation with MS B, MS A gets the call waiting indication. MS A answers the call from MS C and enters into conversation with MS C. Now the number of MS C is displayed on the UI screen of MS A. MS C disconnects the call. There would be no signaling information from the network that the MS C has disconnected the call. But the network would now place MS B back in call with MS A. But since the mobile does not get any signaling information regarding the switch in the call, it would still display the number of MS C in the UI screen. Again the issue arises due to the lack of a specific message in the standards to end a call waiting scenario. Scenario3 MS A cannot reject the waiting call from MS C

| Technology Innovation Gr., Mobile Handset R&D Center 3 3GPP2 Call waiting CR Implementation Idea The above issues exist due to the lack of a proper message to handle this specific scenario. The proposal defined below uses the Order message used in the forward traffic channel. The new Order code “Call Waiting Release” needs to be defined. When the MS C disconnects the call, the network sends a order message with order code “Call Waiting Release” to MS A over the Air interface. The MS A processes this message to handle the release of call from the MS C. This involves killing the call waiting display if the call from MS C is not answered or display of MS B number if the call is already answered To reject the waiting call from MS C, MS A can send the “Call Waiting Release” Order message to the network and MS C will get the intimation from the network that the call is rejected

| Technology Innovation Gr., Mobile Handset R&D Center 4 3GPP2 Call waiting CR Flash with Info (Reverse Traffic Channel) BSMS A MS A and MS B are in conversation BS detects incoming call and sends a Alert or Flash with Info Flash with Info (Fwd Traffic Channel) MS A sees MS C call waiting and decides to answer the call by pressing Send Network mutes speech path to MS B, connects MS C MS A is now in conversation with MS C and MS B is put on hold Order – Call Waiting release (Fwd Traffic Channel) Proposal for 3GPP2 standard Change Request The proposal is to add a new call wa iting release order message in existi ng CDMA 3GPP2 standard in forwar d and reverse traffic channel Order – Call Waiting release (Rev Traffic Channel)

| Technology Innovation Gr., Mobile Handset R&D Center 5 3GPP2 Call waiting CR  User can reject waiting call  Network can indicate that the waiting call has been disconnected at the other end Implementation Advantages