Some switches can be configured to perform cut-through switching on a per-port basis until a user-defined error threshold is reached, when they automatically change to store-and-forward mode. When the error rate falls below the threshold, the port automatically changes back to store-and-forward mode.
LAN switches must use store-and-forward techniques to support multilayer switching. The switch must receive the entire frame before it performs any protocol-layer operations. For this reason, advanced switches that perform Layer 3 switching are store-and-forward devices.
LAN Switching Bandwidth
LAN switches also can be characterized according to the proportion of bandwidth allocated to each port. Symmetric switching provides evenly distributed bandwidth to each port, while asymmetric switching provides unlike, or unequal, bandwidth between some ports.
An asymmetric LAN switch provides switched connections between ports of unlike bandwidths, such as a combination of 10BaseT and 100BaseT. This type of switching is also called 10/100 switching. Asymmetric switching is optimized for client/server traffic flows in which multiple clients simultaneously communicate with a server, requiring more bandwidth dedicated to the server port to prevent a bottleneck at that port.
參考答案:有些交换机可配置进行裁剪通过开关以每港口基础直到用户定义阈值误差达到 当他们自动改变存储转发模式. 当错误率低于门槛,会自动变回港口存储转发模式. 局域网交换机必须使用存储转发技术支持多层交换. 开关接收整个帧之前必须执行的任何协议层作业. 为此,先进的第三层交换开关内部存储转发装置. 蓝鸿震带宽切换开关,也可根据其特点带宽比例分配给每个港口. 开关提供均匀对称带宽每个港口,而不像对称切换规定,或不平等,有些港口之间的带宽. 兰切换开关提供对称连接港口与带宽等多种10baset、100baset. 这种切换开关又称360. 切换不对称是优化客户机/服务器流量发生了多次沟通,同时客户服务器 更需要专门的服务器带宽瓶颈,以防止在端口堵塞.