CN-122002163-A - OTN network transmission method and device based on dynamic bandwidth adjustment

CN122002163ACN 122002163 ACN122002163 ACN 122002163ACN-122002163-A

Abstract

The invention relates to the technical field of optical communication, in particular to an OTN network transmission method and device based on dynamic bandwidth adjustment, which converts an OTN rigid pipeline into an elastic intelligent pipeline, remarkably improves the utilization rate of bandwidth resources, realizes bandwidth millisecond-level agility adjustment by automatically sensing service load change, meets the demand of on-demand instant supply of scenes such as cloud service, 5G slicing and the like, greatly shortens service response time, effectively reduces port power consumption by a speed and power linkage mechanism, meets the development goal of green communication, realizes the technical scheme in a standard OTN frame structure, is perfectly compatible with the existing equipment and operation and maintenance system, supports network smooth evolution, ensures that a multi-time-scale intelligent decision architecture can rapidly cope with burst flow and realize flow shaping by a prediction algorithm, avoids link oscillation, realizes accurate clock synchronization by in-band signaling, and continuously ensures transmission reliability in the whole dynamic adjustment process.

Inventors

LIN XIANGMENG
XI HONGBIAO
JIANG PENGYU
JIANG PAN
HUANG YU
YANG YANFENG

Assignees

中国电子科技集团公司第三十四研究所

Dates

Publication Date: 20260508
Application Date: 20260128

Claims (7)

1. The OTN network transmission device based on dynamic bandwidth adjustment is characterized by comprising a sending end and a receiving end, wherein the sending end comprises a service mapping and buffering module, a load monitoring and bandwidth calculating module, a dynamic bandwidth modulating module, an OTN framing and FEC encoding module, a line interface and an optical transmitting module, and the receiving end comprises an optical receiving and clock data recovering module, an OTN de-framing and FEC decoding module, a dynamic bandwidth demodulator and a service de-mapping and sending module; the service mapping and buffering module is used for receiving the client side signal and asynchronously mapping the client side signal to the ODUk frame payload area, and simultaneously providing an elastic buffer to absorb clock deviation and phase jitter; The load monitoring and bandwidth calculating module is used for monitoring service load and generating a bandwidth adjusting instruction; The dynamic bandwidth modulation module is used for carrying out rate modulation on the OTN data stream according to the instruction; The OTN framing and FEC coding module is used for adding OTN frame overhead to the modulated data stream and performing FEC coding; the line interface and the optical emission module are used for converting the electric signals into optical signals and emitting the optical signals to the optical fibers; the optical receiving and clock data recovery module is used for receiving the optical signal and recovering the clock and the data; The OTN frame decoding and FEC decoding module is used for frame delimitation, analyzing the OTN frame structure and executing FEC decoding; the dynamic bandwidth demodulator is used for recovering the original standard OTN frame rate from the modulated signal; The service demapping and sending module is configured to extract a client signal from an ODUk frame payload and send the client signal to a client device.
2. The OTN network transmission device based on dynamic bandwidth adjustment according to claim 1, wherein, The dynamic bandwidth modulation module comprises a symbol stuffing modulation unit and an overhead reconstruction modulation unit, The symbol stuffing modulation unit changes the average effective data rate by controllably inserting or deleting predefined stuffing symbols in the OTN frame stream; And the overhead reconstruction modulation unit generates a corresponding bandwidth adjustment control word according to the instruction and writes the bandwidth adjustment control word into a pre-configured overhead byte position of the OTN frame.
3. The OTN network transmission device based on dynamic bandwidth adjustment according to claim 2, wherein, The load monitoring and bandwidth calculating module comprises a fast response channel and a slow response channel; the fast response channel realizes millisecond-to-microsecond fast response based on double-threshold comparison; the slow response channel is used for predicting the traffic flow trend of hundreds of milliseconds to seconds in the future, and initiating gentle bandwidth adjustment in advance based on a prediction result so as to avoid link oscillation caused by rapid adjustment.
4. The OTN network transmission device based on dynamic bandwidth adjustment according to claim 1, wherein, The dynamic bandwidth demodulator comprises a symbol filling detection and rejection unit and an overhead analysis and synchronization unit; The symbol filling detection and rejection unit is used for positioning and rejecting all filling symbols inserted by the transmitting end in the data stream; The overhead analysis and synchronization unit controls the frequency and the phase of the data reading clock according to the information of the control word so as to synchronize the data reading clock with the original service clock of the transmitting end.
5. An OTN network transmission method based on dynamic bandwidth adjustment, which is used in the OTN network transmission device based on dynamic bandwidth adjustment as claimed in any one of claims 1 to 4, and is characterized by comprising the following steps: Asynchronously mapping a client side signal to an ODUk frame payload and caching, monitoring the depth of an elastic cache queue through multiple time scales, combining with a flow prediction intelligent decision bandwidth adjustment instruction, dynamically modulating the OTN data flow rate by adopting a symbol filling method or an overhead reconstruction method, framing through the OTN, FEC encoding and photoelectric conversion, and sending to an optical fiber line; Receiving optical signals, completing clock data recovery, OTN frame decoding and FEC decoding, correspondingly executing filling symbol detection rejection or overhead control word analysis by identifying a transmitting end modulation mode, recovering an original data clock to realize accurate synchronization, and finally extracting client signals from the payload and outputting the client signals.
6. The OTN network transmission method based on dynamic bandwidth adjustment according to claim 5, wherein in the steps of asynchronously mapping a client side signal to an ODUk frame payload and buffering, dynamically modulating an OTN data stream rate by a symbol stuffing method or an overhead reconstruction method by using a multi-time scale monitoring elastic buffer queue depth in combination with a traffic prediction intelligent decision bandwidth adjustment instruction, and transmitting the OTN data stream rate to an optical fiber line after OTN framing, FEC encoding and photoelectric conversion, the method comprises the following steps: Asynchronously mapping the client side signal to a payload area of an ODUk frame through a universal framing procedure or a bit synchronous mapping mode, and storing the payload area into an elastic buffer; Continuously monitoring the queue depth of the elastic buffer, comparing the depth with a preset high/low water line threshold value to generate a millisecond-level rapid adjustment instruction, optionally running a lightweight flow prediction algorithm to generate a predictive adjustment instruction, and comprehensively generating a final bandwidth adjustment instruction; the line rate is modulated by a symbol filling method or an overhead reconstruction method, namely, when the symbol filling method is adopted, the filling symbol density rho is calculated, and a predefined IDLE code pattern is inserted into the fixed position of an OTN frame; and adding OTN frame overhead to the modulated data stream, performing FEC coding, and transmitting the data stream to an optical fiber line after photoelectric conversion.
7. The OTN network transmission method based on dynamic bandwidth adjustment according to claim 5, wherein in the steps of receiving an optical signal and completing clock data recovery, OTN deframed and FEC decoding, performing padding symbol detection culling or overhead control word parsing by identifying a modulation mode of a transmitting end accordingly, recovering an original data clock to achieve precise synchronization, and finally extracting a client signal from a payload and outputting, comprising the steps of: converting the optical signal into an electric signal, recovering and extracting clock information through clock data, and finishing the frame decoding and FEC decoding of the OTN; for the symbol filling method, identifying and removing filling symbols, and locking an effective frame arrival interval by a phase-locked loop to generate a synchronous clock; and extracting the client signal from the demodulated and recovered OTN frame payload, and completely transmitting the data to the client device by using the recovered client clock.

Description

OTN network transmission method and device based on dynamic bandwidth adjustment Technical Field The present invention relates to the field of optical communications technologies, and in particular, to an OTN network transmission method and apparatus based on dynamic bandwidth adjustment. Background OTN technology is known as the core technology of the next generation backbone transport network. By introducing the concepts of digital encapsulation, digital multiplexing, digital interleaving and the like, a powerful client signal adaptation, management and scheduling layer is constructed above the optical layer. OTN defines a container (e.g., ODU0/1/2/2 e/3/4/flex) with multiple rate levels, providing transparent transport channels for different rate client signals (e.g., ethernet, SDH/SONET). However, conventional OTN networks are essentially "rigid pipe" based. Once a particular size ODUk channel is allocated for a traffic path, the bandwidth of that channel is typically fixed for the lifetime of the connection. This static feature, in the face of the dynamic traffic pattern of modern network applications, exposes a number of drawbacks: 1. Bandwidth resource rigidification and low utilization-in order to ensure that traffic does not experience packet loss and delay jitter at peak traffic, network planners must allocate bandwidth at peak rates. Statistics show that the average load rate for most data traffic is only 30% -50% of the peak rate. This means that more than half of the precious bandwidth resources are idle most of the time, resulting in huge resource waste and cost pressure. 2. Service provisioning is inflexible in that existing OTN networks typically require manual reconfiguration by a network administrator through a network management system or control plane (e.g., ASON/GMPLS) when a user needs to temporarily increase or permanently adjust bandwidth. The time consumption of the process varies from a few minutes to a few days, and the requirement of bandwidth 'on-demand' supply in the scenes of cloud service, 5G network slicing, data center interconnection and the like can not be met. 3. The energy efficiency is low and the power consumption of OTN ports (particularly high rate ports such as G/400G) is huge. These ports typically operate at full power throughout, regardless of the actual traffic they carry. During periods of low load, a large amount of energy is consumed on links transmitting "no load" or "light load", which is contrary to the green communication goals. In order to increase flexibility, related standards organizations and vendors have explored. For example, ODUflex (GFP) technology can adjust the size of the ODUflex container according to the rate of Constant Bit Rate (CBR) client signals, but it is mainly aimed at circuit-type traffic, and the adjustment process involves control plane signaling and recalculation of network paths, with delays on the order of seconds or longer, and is difficult to cope with traffic bursts on the order of milliseconds and microseconds. In addition, the optical layer-based optical orthogonal frequency division multiplexing (O-OFDM) and variable bandwidth optical transceiver technologies can realize flexibility in optical spectrum granularity, but have high cost, low integration degree with the existing OTN electrical layer management operation and maintenance system, and are difficult to smoothly deploy in the existing network. Thus, there is a need in the industry for an innovative solution that can be implemented on the mainstream OTN electrical layer that is backward compatible with existing equipment, yet provides fine granularity and fast dynamic bandwidth adjustment capability. Disclosure of Invention The invention aims to provide an OTN network transmission method and device based on dynamic bandwidth adjustment, and aims to solve the problem of low bandwidth resource utilization rate. In order to achieve the above objective, in a first aspect, the present invention provides an OTN network transmission device based on dynamic bandwidth adjustment, which includes a transmitting end and a receiving end, wherein the transmitting end includes a service mapping and buffering module, a load monitoring and bandwidth calculating module, a dynamic bandwidth modulating module, an OTN framing and FEC encoding module, a line interface and an optical transmitting module; the service mapping and buffering module is used for receiving the client side signal and asynchronously mapping the client side signal to the ODUk frame payload area, and simultaneously providing an elastic buffer to absorb clock deviation and phase jitter; The load monitoring and bandwidth calculating module is used for monitoring service load and generating a bandwidth adjusting instruction; The dynamic bandwidth modulation module is used for carrying out rate modulation on the OTN data stream according to the instruction; The OTN framing and FEC coding module is used for adding OTN f