以太网无源光网络(EPON)已经在全球得到广泛应用，光线路终端(OLT)设备是EPON的核心。由于EPON是点到多点的共享型网络，网络安全会受到威胁，保护OLT设备对整个EPON有着重要意义。文章介绍了EPON OLT设备防攻击方法，重点介绍了交换芯片在设备防攻击中扮演的重要角色，并举例说明了EPON设备如何防攻击。

EPON has been widely deployed on the globe and Optical Line Terminal (OLT) is its core element. As a shared point-to-multipoint network, its security is subject to menace, so the protection of OLT is of great importance to the entire EPON. In this paper, anti-attack methods for EPON OLT are introduced, with an emphasis on the important roles of switching chips in these methods. Examples are given to explain how the EPON units are protected.