介紹ARP 協(xié)議、Windows 系統(tǒng)中ARP 實現(xiàn)，設(shè)計了一個非法入網(wǎng)檢測及阻止系
統(tǒng)。該系統(tǒng)通過ARP 掃描，實時檢測非法主機（未知主機）接入內(nèi)部網(wǎng)絡(luò)的企圖，并
通過發(fā)送沖突包和其它偽造數(shù)據(jù)包，阻止與內(nèi)部網(wǎng)絡(luò)的其它主機進行信息交換，從而
有效地保護了內(nèi)部網(wǎng)絡(luò)的信息安全。
Abstract: The paper introduces ARP protocol, the implement of ARP in Windows system,
and designs the system of the detection and block on illegal connection to LAN. The
system can detect the illegal host connecting to LAN in real time by scanning LAN, and
block the swap of information between the illegal(unknown) host and other host in LAN
by sending ARP packets resulting in conflicting or error. So the system can protect the
security of information in LAN in effect.
Key words: ARP; illegal connection to LAN; detection; block