公开(公告)号：US06401127B1

公开(公告)日：2002-06-04

申请号：US09304395

申请日：1999-05-04

申请人： Alan Lei ,  Nitin Karkhanis ,  Richard Livingston ,  Uwe Sellentin

发明人： Alan Lei ,  Nitin Karkhanis ,  Richard Livingston ,  Uwe Sellentin

IPC分类号： G06F1300

CPC分类号： H04L1/188 ,  H04L1/0018 ,  H04L1/1825 ,  H04L45/00 ,  H04L45/26 ,  H04L69/324

摘要： A method for computing an ACK timing interval for an ACK timer in a protocol layer LLC type 2 session first measures a time interval between transmission of a frame by a source computer joined to a to a destination computer by an intermediate link, and receipt of a corresponding acknowledgment frame by the source computer from the destination computer. The two events at the source computer, starting a timer upon commencement of transmission of a frame or sequence of frames and the later reception of an acknowledge message indicating receipt of those frames, permits calculation of a measured time interval. The measured time interval is used to compute the bandwidth of the intermediate link. The required ACK timing interval for the ACK timer is then computed in response to the bandwidth, the number of bytes transmitted after starting the ACK timer, and the return time for an acknowledgment message. The ACK timing interval may be recomputed after every transmission of frames and receipt of a corresponding ACK message. The ACK timing interval is thereby dynamically adjusted to conditions on the intermediate link, including natural bandwidth for either a slow or fast link, congestion due to other traffic on the link, etc. The dynamic adjustment of the ACK timing interval prevents inadvertent timeouts of the ACK timer, and so prevents inadvertent breaking of the LLC type 2 reliable transport connection.

摘要翻译： 用于计算协议层LLC类型2会话中的ACK定时器的ACK定时间隔的方法首先测量由中间链路连接到目的地计算机的源计算机发送帧之间的时间间隔，以及接收到 来自目的地计算机的源计算机的相应确认帧。 在源计算机上的两个事件，在帧或帧序列的传输开始时启动定时器以及稍后接收到指示接收到这些帧的确认消息，允许计算测量的时间间隔。 测量的时间间隔用于计算中间链路的带宽。 然后响应于带宽，启动ACK定时器之后发送的字节数以及确认消息的返回时间来计算ACK定时器所需的ACK定时间隔。 可以在每次传输帧和接收到相应的ACK消息之后重新计算ACK定时间隔。 因此，ACK定时间隔被动态地调整到中间链路上的条件，包括慢链路或快速链路的自然带宽，由于链路上的其他业务造成的拥塞等.AH定时间隔的动态调整防止了无意中超时 ACK定时器，因此防止了LLC 2型可靠传输连接的无意中断。