Abstract: Traditional link access control algorithm such as LBRCA（Link Bandwidth Require Control Algorithm） has the problem of high link access rejection probability and low bandwidth resource usage ratio.A model of sharing bandwidth allocation in multi-link is proposed，the features of link bandwidth allocation and QoS level are also discussed.The DBAMQ（dynamic bandwidth allocation and multi-level QoS） link access control algorithm is presented.In this algorithm，the bandwidth is readjusted according to variable QoS level.Experimental results demonstrate that DBAMQ is better than other traditional algorithms in link access successful ratio，system bandwidth utilization and system efficient.DBAMQ is suitable for the application of link control in large-scale broadband network access.

Key words: sharing bandwidth, traffic scheduling, QoS level, system efficient

摘要： 针对传统的基于带宽请求链路接入控制算法（Link Bandwidth Require Control Algorithm，LBRCA）的接入成功率和系统带宽利用率不高的问题，设计了一种多链路接入共享带宽分配模型，分析了链路带宽分配和QoS等级的特点，提出一种动态带宽分配分级QoS链路接入控制算法DBAMQ（Dynamic Bandwidth Allocation and Multi-level QoS），该算法在保证某QoS等级的基础上允许动态地对系统的带宽进行重分配。实验结果表明，该算法在接入成功率、系统总带宽利用率和系统效能等都比传统链路接入控制算法好，适合于大规模宽带接入链路控制的应用。

关键词: 共享带宽, 流量调度, 服务质量等级, 系统效能