Abstract: A device, system and method for preventing audio loss is provided. A device receives scheduling data, for a plurality of timeslots, indicative of when different communication types are to occur in a present voicecall, the plurality of timeslots including at least one data timeslot for transmitting data on the present voicecall. When a state of the present voicecall associated with a potential collision with the data for transmission in the at least one data timeslot is determined, the device cancels transmission of the data in the at least one data timeslot.

Abstract: A device, system and method for preventing audio loss is provided. A device receives scheduling data, for a plurality of timeslots, indicative of when different communication types are to occur in a present voicecall, the plurality of timeslots including at least one data timeslot for transmitting data on the present voicecall.

Abstract: A method and apparatus for assigning a talk group to a radio within a communication system is provided herein. During operation a router receives a communication from a radio over a channel. The communication uses a first talk group that is not assigned to the channel. In response, the router will forward identification information for the user over the channel using a pre-arranged second talk group. Once communication is received using the second talk group (at, for example a console), the receiver will program the radio with an appropriate talk group.

Abstract: A method and apparatus for assigning a talk group to a radio within a communication system is provided herein. During operation a router receives a communication from a radio over a channel. The communication uses a first talk group that is not assigned to the channel. In response, the router will forward identification information for the user over the channel using a pre-arranged second talk group. Once communication is received using the second talk group (at, for example a console), the receiver will program the radio with an appropriate talk group.

Abstract: Disclosed is a radio system, method, and device for a mobile station to indicate to an authentication controller, in an authentication response message, which of a plurality of group key link layer encryption keys (GKEK)s it currently has in its possession, and to work with the authentication controller to more intelligently manage multiple GKEKs. The authentication controller can use the information obtained from the authentication response message to determine which of a plurality of GKEKs to advertise in a key announcement broadcast. Furthermore, individual requests for a future LLE key (LEK) to be used for link layer encryption (LLE) encrypting and decrypting inbound and outbound group communications between base station(s) and mobile station(s) are responded to with a broadcast GKEK-encrypted transmission including the future LEK. Only the requesting mobile station transmits an acknowledgment packet in response to the broadcast.

Abstract: Disclosed is a method of rekeying radios for link layer encryption (LLE) in a radio network using a bifurcated crypto period. During a first portion of a first LLE crypto period during which a first LLE key (LEK) is used to LLE encrypt communications between a base station and mobile stations operating within a corresponding coverage area of the base station, a radio network communications device prevents individual ones of the mobile stations from requesting a second LEK to be used during a second LLE crypto period after the first LLE crypto period. During a second portion of the first LLE crypto period, the radio network communications device allows individual ones of the mobile stations to request the second LEK. A mobile station configured to operate in accordance with the bifurcated crypto period, and provide information regarding keys in its possession via an authentication response ISP, is also disclosed.

Abstract: Disclosed is a radio system, method, and device for a mobile station to indicate to an authentication controller, in an authentication response message, which of a plurality of group key link layer encryption keys (GKEK)s it currently has in its possession, and to work with the authentication controller to more intelligently manage multiple GKEKs. The authentication controller can use the information obtained from the authentication response message to determine which of a plurality of GKEKs to advertise in a key announcement broadcast. Furthermore, individual requests for a future LLE key (LEK) to be used for link layer encryption (LLE) encrypting and decrypting inbound and outbound group communications between base station(s) and mobile station(s) are responded to with a broadcast GKEK-encrypted transmission including the future LEK. Only the requesting mobile station transmits an acknowledgment packet in response to the broadcast.

Abstract: Disclosed is a radio system, method, and device for a mobile station to indicate to an authentication controller, in an authentication response message, which of a plurality of group key link layer encryption keys (GKEK)s it currently has in its possession, and to work with the authentication controller to more intelligently manage multiple GKEKs. The authentication controller can use the information obtained from the authentication response message to determine which of a plurality of GKEKs to advertise in a key announcement broadcast. Furthermore, individual requests for a future LLE key (LEK) to be used for link layer encryption (LLE) encrypting and decrypting inbound and outbound group communications between base station(s) and mobile station(s) are responded to with a broadcast GKEK-encrypted transmission including the future LEK. Only the requesting mobile station transmits an acknowledgment packet in response to the broadcast.

Abstract: Disclosed is a radio system, method, and device for a mobile station to indicate to an authentication controller, in an authentication response message, which of a plurality of group key link layer encryption keys (GKEK)s it currently has in its possession, and to work with the authentication controller to more intelligently manage multiple GKEKs. The authentication controller can use the information obtained from the authentication response message to determine which of a plurality of GKEKs to advertise in a key announcement broadcast. Furthermore, individual requests for a future LLE key (LEK) to be used for link layer encryption (LLE) encrypting and decrypting inbound and outbound group communications between base station(s) and mobile station(s) are responded to with a broadcast GKEK-encrypted transmission including the future LEK. Only the requesting mobile station transmits an acknowledgment packet in response to the broadcast.

Abstract: A secure communication system (100) that is capable of over-the-air-rekeying (OTAR) employs a key management controller (108) to provide secure communications for a requested call. The key management controller determines (403) when the requested call has been initiated and identifies (405) some of the plurality of radios as being members of the requested call. A call key is then transmitted (409) to the members of the requested call where it is used (514) for the duration of the requested call. In this manner, secure communications between the members of the requested call is provided.

Abstract: A key management system permits a high degree of autonomous rekeying activity by communication units (105) in a secure communication system (100). Responsive to time reference information transmitted by a key management controller (101), the communication units (105) activate a designated key index at a predetermined activation time. If conditions so indicate, a communication unit may transmit a rekey request.

Abstract: A single sync field (501) and multiple messages or message segments (503, 507, 511, and 515) are chained (407) together and encrypted (407) as a whole. When this encrypted chained message is received, it is decrypted as a whole (605), or in part (613) by setting up (609) and filling (611) a holding register with the encryption state of the encrypting device.