摘要：進(jìn)行UDP協(xié)議通信時(shí)，發(fā)送端和接收端的狀態(tài)是相對(duì)獨(dú)立的，發(fā)送端不與接收端建立連接，而是不停向接收端發(fā)送，為了確保不丟失報(bào)文，上位機(jī)采取了按固定次數(shù)重發(fā)相同內(nèi)容報(bào)文的機(jī)制。這種機(jī)制雖然可以有效確保報(bào)文不丟失，但大量冗余數(shù)據(jù)報(bào)被發(fā)送，網(wǎng)絡(luò)資源利用率不高。顯然重發(fā)次數(shù)越多，冗余數(shù)據(jù)報(bào)越多，效率越低。要想有效保證數(shù)據(jù)報(bào)準(zhǔn)確發(fā)送的同時(shí)又不產(chǎn)生過多冗余數(shù)據(jù)報(bào)，那么重復(fù)發(fā)送的次數(shù)的確定就成為問題的關(guān)鍵。以下給出一種確定上位機(jī)重發(fā)次數(shù)的方法。
　　關(guān)鍵詞：ARM；Linux；交叉編譯環(huán)境；UDP協(xié)議；重發(fā)機(jī)制；重發(fā)次數(shù)
　　中圖分類號(hào)：TP393文獻(xiàn)標(biāo)識(shí)碼：A文章編號(hào)：1009-3044(2011)13-3001-03
　　The Application Research of Communicating Based on ARM-Linux Environment and UDP-Protocol
　　CUI Hao, SHAO Ping-fan
　　(Wuhan University of Science and Technology, Wuhan 430000, China)
　　Abstract: The sender and recEiver are relatively independent when communicating under UDP- protocol, the sender resending messages to recEIver times instead of creating a connection. A resend-mechanism that the key-messages were send by upper computer in fixed times, was used in order to ensuring not to lost key-message. Although the resend-mechanism can ensure that the key-message wouldn’t be lose anyway, but abundant of redundancy messages