Source: https://patents.google.com/patent/US20050036497A1/en
Timestamp: 2020-01-22 03:03:42
Document Index: 120884627

Matched Legal Cases: ['§119', 'Application No. 2003', 'art 503', 'art 503', 'art 504', 'art 504', 'art 504', 'art 505', 'art 502', 'art 505', 'art 504', 'art 503', 'art 503', 'art 504', 'art 504', 'art 505', 'art 505', 'art 402', 'art 503']

US20050036497A1 - Frame transmission/reception system, frame transmitting apparatus, frame receiving apparatus, and frame transmission/reception method - Google Patents
US20050036497A1
US20050036497A1 US10/917,923 US91792304A US2005036497A1 US 20050036497 A1 US20050036497 A1 US 20050036497A1 US 91792304 A US91792304 A US 91792304A US 2005036497 A1 US2005036497 A1 US 2005036497A1
US10/917,923
2003-08-14 Priority to JPP2003-207593 priority
2004-08-13 Application filed by NTT Docomo Inc filed Critical NTT Docomo Inc
2004-08-13 Assigned to NTT DOCOMO, INC. reassignment NTT DOCOMO, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KAWAKAMI, HIROSHI
2005-02-17 Publication of US20050036497A1 publication Critical patent/US20050036497A1/en
This application claims priority under 35 U.S.C. §119 to Japanese Patent Application No. 2003-207593 filed Aug. 14, 2003, the entire content of which is hereby incorporated by reference.
As a third-generation mobile communication system there is the UMTS (Universal Mobile Telecommunication System) standardized by 3GPP (3rd Generation Partnership Project). In the radio access method of UMTS, communication using a unique radio protocol is carried out between a physical layer and an application layer. The radio protocol is set between a mobile station and a radio network control station (RNC), and consists of sublayers of PDCP (Packet Data Convergence Protocol), RLC (Radio Link Control), and MAC (Medium Access Control). Among these the RLC sublayer (cf. Non-patent Document 1 cited below) establishes a connection at a time of a start of communication to permit acknowledgement type and unacknowledgement type communication. The RLC sublayer determines one of three modes: TM (Transparent Mode), UM (Unacknowledgement Mode), and AM (Acknowledgement Mode) at the time of establishing the RLC connection. TM has a function of only dividing upper-layer data and transferring it to a lower sublayer (or the reverse). UM and AM enable upper-layer data to be loaded in a divided or multiplexed state on RLC-PDU, and are suitable for transfer of variable-length data such as IP (Internet Protocol) packets. UM has no retransmission function, while AM has a function of correcting an error due to degradation of quality in a radio section by retransmission control. These modes are set on a connection-by-connection basis and it is necessary to independently set a connection for a case of handling a data flow with need for retransmission and a connection for a case of handling a data flow without need for retransmission.
Non-patent Document 1: 3GPP, TS23.107, “Radio Link Control (RLC) protocol specification,” December 2002.
As a premise for the description of the present embodiment a network 1 a (frame transmission/reception system) will be described using FIG. 1. This network 1 a is comprised of a mobile communication network 10, a mobile station 20, and a mobile network 30. The mobile communication network 10 includes a base station 101, a radio link control station 102, and a core network 103. The mobile station 20 has a radio interface to access the mobile communication network 10 and is linked to the mobile network 30 consisting of at least one communication terminal. The base station 101 has a radio interface to the mobile station 20, and an interface to the radio link control station 102. The radio link control station 102 is able to communicate with the exterior of the mobile communication network 10 through the core network 103. In the network 1 a of FIG. 1, the base station 101 and the radio link control station 102 are described as separate nodes, but they can also be configured as a single node. The mobile station 20 transfers data flows from many communication terminals of the mobile network 30 through one radio interface to the mobile communication network 10.
Examples of QoS identifiers will be described with reference to FIGS. 4. The example of FIG. 4 (a) is an example in which whether it is necessary to perform retransmission is determined from the QoS information of each data packet and in which an identifier is provided based on the determination. In the example of FIG. 4 (a), the QoS identifier of “0” indicates an unacknowledgement type frame, and the QoS identifier of “1” an acknowledgement type frame. The example of FIG. 4 (b) is an example in which the QoS information of each data packet is mapped as it is. In the example of FIG. 4 (b), it is necessary to preliminarily determine which type of retransmission control should be performed for each QoS class of data packet, between the frame transmitting apparatus 40 and the frame receiving apparatus 50.
In order to describe a method of transmission/reception of frames in the network 1 a of the present embodiment, the operation of the aforementioned frame transmitting apparatus 40 and frame receiving apparatus 50 will be described in detail with reference to FIG. 5. Each “U” in FIG. 5 indicates an unacknowledgement type frame. In the example of FIG. 5, the sequence number reference part 503 of the frame receiving apparatus 50 detects a loss of frame 3. The sequence number reference part 503 instructs the buffer part 504 to buffer a subsequent acknowledgement type frame, and then the buffer part 504 buffers frame 4. When receiving the frame 3 retransmitted thereafter, the buffer part 504 performs the ordering control and the packet reconfiguration part 505 reconfigures a packet. Since an unacknowledgement type frame is directly outputted from the QoS reference part 502 to the packet reconfiguration part 505, it is not subjected to the buffer process in the buffer part 504.
The example in which the sequence number management is carried out for each data flow identifier will be described in detail with reference to FIG. 6. Each “U” in FIG. 6 indicates an unacknowledgement type frame. A numeral before a hyphen in each frame indicates a data flow identifier, and a numeral after a hyphen a sequence number in each data flow. In the example of FIG. 6, the sequence number reference part 503 of the frame receiving apparatus 50 detects a loss of frame 1-2. When the sequence number reference part 503 instructs the buffer part 504 to buffer a subsequent acknowledgement type frame of the same data flow, the buffer port 504 buffers frame 1-3. When receiving the frame 1-2 retransmitted thereafter, the buffer part 504 performs the ordering control of frames and the packet reconfiguration part 505 reconfigures a packet. Frames 2-1 to 2-2 of a different data flow are directly outputted without being buffered, to the packet reconfiguration part 505.
The operation of the present embodiment will be described with reference to the flowchart shown in FIG. 7. The frame building part 402 of the frame transmitting apparatus 40 builds frames for transmission of a data packet and provides each of the built frames with a QoS identifier (step SO 1).
The sequence number reference part 503 determines whether a frame is lost, for each acknowledgement type frame, and requests retransmission of a lost acknowledgement type frame (step S05).
1. A frame transmission/reception system for transferring a data packet on a connection established prior to communication, the system comprising:
2. A frame transmitting apparatus used in a frame transmission/reception system for transferring a data packet on a connection established prior to communication, the frame transmitting apparatus comprising:
3. The frame transmitting apparatus according to claim 2, wherein the data packet is comprised of a plurality of data flows, and
4. The frame transmitting apparatus according to claim 2, comprising number providing means for providing each acknowledgement type frame with a sequence number for each established connection.
5. The frame transmitting apparatus according to claim 3, comprising number providing means for providing each acknowledgement type frame with a sequence number for each established connection and for each data flow identifier.
6. A frame receiving apparatus used in a frame transmission/reception system for transferring a data packet on a connection established prior to connection, the frame receiving apparatus comprising:
7. The frame receiving apparatus according to claim 6, comprising holding means for, when the retransmission requesting means requests retransmission of the acknowledgement type frame, temporarily holding a previously received acknowledgement type frame until reception of the acknowledgement type frame retransmitted according to the request for the retransmission.
8. The frame receiving apparatus according to claim 7, wherein the data packet is comprised of a plurality of data flows, and
9. A frame transmission/reception method of transferring a data packet on a connection established prior to communication, the frame transmission/reception method comprising:
US10/917,923 2003-08-14 2004-08-13 Frame transmission/reception system, frame transmitting apparatus, frame receiving apparatus, and frame transmission/reception method Abandoned US20050036497A1 (en)
JPP2003-207593 2003-08-14
US20050036497A1 true US20050036497A1 (en) 2005-02-17
US10/917,923 Abandoned US20050036497A1 (en) 2003-08-14 2004-08-13 Frame transmission/reception system, frame transmitting apparatus, frame receiving apparatus, and frame transmission/reception method
US20180331790A1 (en) * 2006-04-12 2018-11-15 Tq Delta, Llc Packet retransmission and memory sharing
US10484140B2 (en) * 2006-04-12 2019-11-19 Tq Delta, Llc Packet retransmission and memory sharing
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:KAWAKAMI, HIROSHI;REEL/FRAME:015705/0400