Method and device for dynamic bandwidth allocation in gigabit passive optical network

Abstract

The invention relates to a method and a device for dynamic bandwidth allocation in gigabit passive optical network, wherein the method comprises the steps: at first, predicating the bandwidth of current Alloc-ID, regarding the predication value as input speed of a token bucket; then computing DBA bandwidth required by the current Alloc-ID and comparing the DBA bandwidth with a current token number of the token bucket, if the DBA bandwidth is smaller than the token number, allocating relative bandwidth to the current Alloc-ID and writing the allocated bandwidth into a BWMAP table; and sending the BWMAP table to an optical network unit; the device comprises a T-CONT flow policy table, a flow statistic module, a DBRu table module, a bandwidth predication module, a token bucket flow control module, a bandwidth allocation module, a BWMAP table configuration module, a BWMAP table sending module and a scheduling cycle control module. The method and the device enhance the response speed for the bandwidth allocation of T-CONT.

Description

technical field [0001] The present invention relates to the field of Gigabit-capable Passive Optical Network (GPON), in particular to a method and device for Dynamic Bandwidth Assignment (DBA) in GPON. Background technique [0002] GPON is a gigabit optical access network consisting of OLT (Optical Line Terminal, Optical Line Terminal), ODN (Optical Distribution Network, Optical Distribution Network) and ONU (Optical Network Unit, Optical Network Unit). GPON is a one-to-many tree structure in physical connection. Through ODN connection, data transmission adopts downlink (OLT to ONU) broadcast and uplink (from ONU to OLT) time division multiplexing (TDM). In order to avoid conflicts, OLT Allocate an uplink time slot for each ONU, and the ONU can only transmit data within the authorized time slot. The process of OLT arranging time slots for ONU is the uplink DBA process in GPON. The bandwidth allocated for reporting and configuration parameters changes dynamically. [0003] ...

AI Technical Summary

Problems solved by technology

[0043] In the GPON system test, it is found that if the R assigned to the ONU upstream T-CONT M When the data packet is small and there is a large data packet in the logical cache of the ONU, the T-CONT must obtain multiple authorizations to upload the large data packet from the ONU to the OLT, which will inevitably lead to a large packet delay , which is not conducive to the quality of service (Quality of Service, QOS) index of the whole system

At the same time, it can be seen that formula (3) is a relatively short-term rate calculation formula, but R F , R A , R M For a relatively long-term traffic statistics, in practice, a data stream may have continuous large traffic, and in a relatively long-term perspective, its traffic may be much smaller than the long-term statistical results

If R NA or R BE The traffic distribution according to R F and R A If the sum of the two is used as the only parameter, it will cause the bandwidth allocation response for this T-CONT to be too slow

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