# US 2008/0187138 A1 · Apparatus and method for determining uplink ciphering activation time in universal mobile telecommunications system user equipment > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0187138 A1 - Document ID: US20080187138A1 - Status: Published application - Kind: A1 - Application number: 12/062,415 - Filed: 2008-04-03 - Published: 2008-08-07 - Earliest claimed: 2003-08-15 - Assignees: M-Stack Limited - Inventors: NICOLA M. FUNNELL; ANDREW FARNSWORTH; ROBERT J. HARRISON - Web page: https://patentgrep.com/patent/US20080187138A1 ## CPC - H04L 63/0428: {wherein the data content is protected, e.g. by encrypting or encapsulating the payload} - H04L 47/34: ensuring sequence integrity, e.g. using sequence numbers - H04W 12/037: of the control plane, e.g. signalling traffic - H04W 24/00: Supervisory, monitoring or testing arrangements - H04W 74/06: using polling - H04W 84/04: Large scale networks; Deep hierarchical networks - H04W 84/18: Self-organising networks, e.g. ad-hoc networks or sensor networks - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract The details of an apparatus and method for determining uplink ciphering activation time in universal mobile telecommunications system user equipment are disclosed herein. The ciphering activation time is determined for radio bearers other than RB2 by measuring the data rate on each target radio bearer during the time that it takes for a polling or RRC message sent from the user equipment UE to be acknowledged by the network UTRAN. For RB2, the uplink ciphering activation time is determined by taking into account the size of the RRC response message and the data already queued on RB2 for transmission. ## Claims ### Claim 1 A method of determining uplink ciphering activation time in a user equipment (UE), the UE configurable for communication with a telecommunications network over a communications channel comprising a radio bearer, the method comprising: receiving a message comprising indicia to change ciphering configuration; determining a size of a response message to the message, the response message configurable to be transmitted from the UE via the communications channel using one or more protocol data units (PDUs); using the determined size and a data rate in determining the uplink ciphering activation time; inserting the uplink ciphering activation time into the response message and queuing the response message for transmission. ### Claim 2 (depends on 1) The method of claim 1 where determining a size comprises inserting a value to the response message, the value an estimated uplink ciphering activation time. ### Claim 3 (depends on 2) The method of claim 2 where the value is a dummy value. ### Claim 4 (depends on 1) The method of claim 1 where determining a size comprises accessing a table comprising maximum message sizes, and identifying a maximum size of message for use in determining the response message size. ### Claim 5 (depends on 1) The method of claim 1 comprising sending the response message; disallowing any messages from being sent over the communications channel until receipt of a message comprising acknowledgement of the response message. ### Claim 6 (depends on 1) The method of claim 1 comprising sending the response message; allowing further messages to be sent over the communications channel until the response message is acknowledged. ### Claim 7 (depends on 1) The method of claim 1 where determining an uplink ciphering activation time is further based on a number of queued messages on the radio bearer's queue. ### Claim 8 (depends on 1) The method of claim 1 where the communications channel comprises signalling on radio bearer 2 (RB2). ### Claim 9 (depends on 1) The method of claim 1 where the response message is sent from the radio resource control (RRC). ### Claim 10 (depends on 1) The method of claim 1 further comprising sending a message of the determined size; receiving a message comprising indicia that the sent message is acknowledged by the telecommunications network; determining an amount of time that passed between the sending and the receiving; and using the determined amount of time in determining the uplink ciphering activation time. ### Claim 11 (depends on 1) The method of claim 1 where the telecommunications network is a UMTS Terrestrial Radio Access Network (UTRAN) compliant communications network. ### Claim 12 User equipment (UE) for determining an uplink ciphering activation time (UCAT) applicable to a communications channel on the UE, the communications channel compliant with a UMTS Terrestrial Radio Access Network (UTRAN), the UCAT usable to determine a time at which a new ciphering configuration for an uplink is to be implemented, the UE comprising: a processor configured to generate a response message after received a ciphering change request message, the response message configurable for sending on a radio bearer, the response message configured to include the UCAT, and, the response message having a size; where the processor is further configured to calculate the UCAT based on the determined size and a data rate, and, to include the calculated UCAT in the response message. ### Claim 13 (depends on 12) The UE of claim 12 where the processor is further configured to calculate the size of the response message by including a example value in the response message comprising an estimated uplink ciphering activation time. ### Claim 14 (depends on 13) The UE of claim 13 where the example value is a dummy value. ### Claim 15 (depends on 12) The UE of claim 12 where the processor is further configured to calculate the size of the response message by accessing a table comprising maximum message sizes, and identifying a maximum size of message for use as a response message. ### Claim 16 (depends on 12) The UE of claim 12 where the processor is further configured to determine a time, the time based on sending a message having a substantially same size as the size of the response message, to the receipt of a message comprising indicia that the sent message was acknowledged by the telecommunications network; and to use the determined time to calculate a UCAT. ### Claim 17 A computer program comprising code on a computer readable medium configured such that when the program product is run on a processor in a user equipment (UE), it causes the UE to perform: configuring a response message after received a ciphering change request message, the configured response message to be usable for sending on a radio bearer and to be receivable by a UMTS Terrestrial Radio Access Network (UTRAN) compliant communications network; determining a size of the response message; determining an uplink ciphering activation time using the determined size and a data rate; incorporating the determined uplink ciphering activation time in the response message. ### Claim 18 (depends on 17) The computer program of claim 17 where the code, when run on a UE, causes the UE to keep track of an amount of time between the sending of a message of the determined size and the receipt of a message comprising indicia that the sent message is acknowledged by the telecommunications network, and, using the determined amount of time in determining the uplink ciphering activation time. ### Claim 19 (depends on 17) The computer program of claim 17 where the code, when run on a UE, causes the UE to calculate the size of the response message by including a example value in the response message comprising an estimated uplink ciphering activation time. ### Claim 20 (depends on 17) The computer program of claim 17 where the code, when run on a UE, causes the UE to calculate the size of the response message by accessing a table comprising maximum message sizes, and identifying a maximum size of message for use as a response message.