# US 10,873,535 B2 · Method and apparatus for avoiding packet fragmentation in mobile communications > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,873,535 B2 - Document ID: US10873535B2 - Status: Granted - Kind: B2 - Application number: 16/039,572 - Filed: 2018-07-19 - Published: 2019-02-14 - Granted: 2020-12-22 - Earliest claimed: 2017-08-10 - Assignees: Mediatek Inc. - Applicants: MediaTek Inc. - Inventors: Rohit Naik; Chien-Chun Huang-Fu; Sami Jutila - Web page: https://patentgrep.com/patent/US10873535B2 ## CPC - H04L 47/36: by determining packet size, e.g. maximum transfer unit [MTU] - H04W 24/02: Arrangements for optimising operational condition - H04W 76/12: Setup of transport tunnels - 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 Various solutions for avoiding packet fragmentation with respect to user equipment and network apparatus in mobile communications are described. An apparatus may determine a first maximum transmission unit (MTU) configuration of a session via a first network interface. The apparatus may determine a second MTU configuration of the session via a second network interface. The apparatus may determine a tunnel overhead size between the second network interface and the first network interface. The apparatus may select a transport protocol to generate a packet according to the second MTU configuration and the tunnel overhead size. The apparatus may transmit the packet via the second network interface. ## Claims ### Claim 1 A method, comprising: determining, by a processor of an apparatus, a first maximum transmission unit (MTU) configuration of a session via a first network interface; determining, by the processor, a second MTU configuration of the session via a second network interface; determining, by the processor, a tunnel overhead size between the second network interface and the first network interface; selecting, by the processor, a transport protocol to generate a packet according to the second MTU configuration and the tunnel overhead size; and transmitting, by the processor, the packet via the first network interface and the second network interface sequentially, wherein the first network interface is associated with a first radio access technology and the second network interface is associated with a second radio access technology different from the first radio access technology. ### Claim 2 (depends on 1) The method of claim 1, further comprising: decreasing, by the processor, the tunnel overhead size from the second MTU configuration when selecting the transport protocol. ### Claim 3 (depends on 1) The method of claim 1, wherein the determining of the second MTU configuration comprises adding a new configuration to the session, or modifying an existing configuration of the session. ### Claim 4 (depends on 1) The method of claim 1, wherein the session comprises a plurality of data paths and a plurality of MTU configurations corresponding to each data path. ### Claim 5 (depends on 4) The method of claim 4, wherein the plurality of data paths comprise a signaling path and a data transmission path. ### Claim 6 (depends on 1) The method of claim 1, wherein the transmitting comprises transmitting the packet through the first network interface and the second network interface sequentially. ### Claim 7 (depends on 1) The method of claim 1, wherein the transport protocol comprises a transmission control protocol (TCP), a user datagram protocol (UDP), or a stream control transmission protocol (SCTP). ### Claim 8 (depends on 1) The method of claim 1, further comprising: determining, by the processor, a plurality of MTU configurations of the session via a plurality of network interfaces; determining, by the processor, the tunnel overhead size among the plurality of network interfaces; selecting, by the processor, the transport protocol to generate the packet according to the plurality of MTU configurations and the tunnel overhead size; and transmitting, by the processor, the packet via the plurality of network interfaces. ### Claim 9 (depends on 1) The method of claim 1, wherein the tunnel overhead size comprises at least one of an internet protocol security (IPsec) overhead size, a generic routing encapsulation (GRE) overhead size, or a tunneling protocol overhead size. ### Claim 10 (depends on 1) The method of claim 1, wherein the first network interface comprises a Long-Term Evolution (LTE) interface, and wherein the second network interface comprises a wireless local area network (WLAN) interface. ### Claim 11 An apparatus, comprising: a transceiver capable of wirelessly communicating with a plurality of nodes of a wireless network; and a processor communicatively coupled to the transceiver, the processor capable of: determining a first maximum transmission unit (MTU) configuration of a session via a first network interface; determining a second MTU configuration of the session via a second network interface; determining a tunnel overhead size between the second network interface and the first network interface; selecting a transport protocol to generate a packet according to the second MTU configuration and the tunnel overhead size; and transmitting, via the transceiver, the packet via the first network interface and the second network interface sequentially, wherein the first network interface is associated with a first radio access technology and the second network interface is associated with a second radio access technology different from the first radio access technology. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the processor is further capable of: decreasing the tunnel overhead size from the second MTU configuration when selecting the transport protocol. ### Claim 13 (depends on 11) The apparatus of claim 11, wherein, in the determining the second MTU configuration, the processor is further capable of adding a new configuration to the session, or modifying an existing configuration of the session. ### Claim 14 (depends on 11) The apparatus of claim 11, wherein the session comprises a plurality of data paths and a plurality of MTU configurations corresponding to each data path. ### Claim 15 (depends on 14) The apparatus of claim 14, wherein the plurality of data paths comprise a signaling path and a data transmission path. ### Claim 16 (depends on 11) The apparatus of claim 11, wherein, in the transmitting, the processor is further capable of transmitting the packet through the first network interface and the second network interface sequentially. ### Claim 17 (depends on 11) The apparatus of claim 11, wherein the transport protocol comprises a transmission control protocol (TCP), a user datagram protocol (UDP), or a stream control transmission protocol (SCTP). ### Claim 18 (depends on 11) The apparatus of claim 11, wherein the processor is further capable of: determining a plurality of MTU configurations of the session via a plurality of network interfaces; determining the tunnel overhead size among the plurality of network interfaces; selecting the transport protocol to generate the packet according to the plurality of MTU configurations and the tunnel overhead size; and transmitting the packet via the plurality of network interfaces. ### Claim 19 (depends on 11) The apparatus of claim 11, wherein the tunnel overhead size comprises at least one of an internet protocol security (IPsec) overhead size, a generic routing encapsulation (GRE) overhead size, or a tunneling protocol overhead size. ### Claim 20 (depends on 11) The apparatus of claim 11, wherein the first network interface comprises a Long-Term Evolution (LTE) interface, and wherein the second network interface comprises a wireless local area network (WLAN) interface.