WLAN网管系统的现状和发展

2001年以来，全球WLAN（无线局域网）市场应用的瓶颈被打破，中国也迎来了WLAN商业化运作和服务的春天，WLAN为我们带来了一种全新的、灵活的工作方式，同时也带来了新的挑战，本文将对WLAN网络管理的主要内容和具体指标进行阐述，并对各大厂商的WLAN网管产品进行简单介绍和比较。     

利用ACL构建校园网安全体系的研究

随着网络应用的普及深入。校园网在学校中的教学、科研和管理中发挥着越来越重要的作用。如何构建一个高安全的校园网成为每个学校面临的问题。利用ACL可以从限制网络流量、限制上网时间、防止网络病毒以及限制访问的网站来加强校园网的安全。     

网络设备的三个非主要配置及实例

通过路由器的ACL功能展示来明确访问控制列表的作用,即对源IP地址、目的IP地址、源端口、目的端口的筛选、限制,建立通信规则,进而达到访问控制的目的。通过NAT转换配置实例,了解NAT、动态地址NAT和端口多路复用地址转换三种技术类型及配置原则。多个VIAN端口汇聚,即可以在一条物理线路上实现多个虚拟网络通讯,为参与Trunk的VLAN打上标记（VLANID）并和对端设备Trunk的VLANID相对应,是完成多个VtAN端口汇聚的必要条件。     

An Alternative Mechanism of Non-contact Anterior Cruciate Ligament Injury During Jump-landing: In-vitro Simulation

In the United States, an estimated 100,000 anterior cruciate ligament (ACL) injuries occur every year. Despite decades of research, to this date, the mechanism or mechanisms of non-contact ACL injuries are not well understood. This is primarily because trials cannot be conducted on live subjects to understand the injury mechanism, and it is difficult to instrument a live human knee to measure the response of tissues during dynamic activities. In this paper, we present a dynamic knee injury simulator capable of in-vitro modeling of the ACL injury during jump-landing activity. This system was used to simulate jump-landing on cadaveric knees and to successfully test which conditions would result in isolated ACL injury. A restricted flexion of the hip (a hip that flexes minimally or not at all during landing), combined with low quadriceps and hamstring force levels during landing were found to be conducive to ACL injury. Elevated levels of quadriceps force prevented the injury from occurring even under restricted hip flexion conditions. The measured strain rates in the ACL tissue during injury causing activities were over 250%/s.     

包分类算法在防火墙中的应用研究

包分类算法的性能直接影响数据包的收发速度,决定了网络的时延和吞吐量。防火墙中使用分类算法进行过滤规则的匹配查找,能有效降低规则匹配搜索时间,极大地提升防火墙的性能。递归流分类（RFC,Recursive Flow Classification）算法查找速度快,但预处理时间长,存储开销大。现在RFC算法的基础上,结合哈希树算法对数据包各字段分开处理。将两种算法结合,综合考虑了空间和时间性能,不仅减少了存储开销,而且能保持相对快的查找速度。     

浅谈防火墙

互联网的普及 ,宽带的接入 ,局域网从百兆升级到千兆 ,新的网络给工作带来极大的便利 ,但同时也带来了一些新的安全隐患。越来越多的企业在网络边界安装了防火墙 ,阻止来自外部的攻击。本文简要介绍防火墙基本类型、配置 ,并以Firewall- 1为例说明了防火墙安全功能及其它能力。     

Notes数据库中存取控制的自维护

Lotus Notes开发平台是一个面向非结构化信息领域优秀的通信处理软件和群件平台。本文将Notes数据库中存取控制安全机制和传统的关系数据库相结合,根据人员工作的调整自动改变人员在Notes系统中的相应权限,实现Notes存取控制安全机制的自维护     

利用广电网QoS架设基于FTP的新闻传输网

通过利用广电宽带网的市县高速联网,设置各县中心三层思科交换机3550和市中心思科路由器做QoS限速策略质量服务和ACL（访问控制列表）,架设基于FTP（文件传输协议）的吉安地区13个县市电视台新闻素材传输网。     

Novel method for transferring access control list rules to synchronize security protection in a locator/identifier separation protocol environment with cross‐segment host mobility

Extended access control lists (ACLs) are used to filter packets for network security. However, in current network frameworks, ACL rules are not transferred simultaneously with devices that move across network segments. The Internet Engineering Task Force proposed the Locator/Identifier Separation Protocol (LISP), which enables routers (xTRs) to configure ACL rules for blocking immobile endpoint identifiers (EIDs). However, when an EID moves from the original xTR to a new xTR, the ACL rules at the original xTR cannot be transferred with the EID. Thus, the new xTR lacks the corresponding ACL rules to effectively block the EID, resulting in security risks. The highlights of this study are as follows. First, a method is proposed for dynamically transferring ACL rules in LISP environments and frameworks. Second, the map‐register and map‐notify protocols were combined to encapsulate and transfer the ACL rules and thus obviate an additional process required to transfer these rules. Third, the experimental results verified that the proposed method can be used to achieve synchronized security protection in an LISP environment involving cross‐segment EID movements.     

Effects of Lower-limb Muscle Fatigue,Cardiopulmonary Fatigue,and Brain FatigueTasks on One-legged Landing Motion

Objective: Anterior cruciate ligament (ACL) injury is one of the most frequent sportsinjuries, and previous studies have shown that fatigue is a risk factor for sports injuries.This study aimed to inform prevention of ACL injury by investigating how exercise and desk tasks affect trunk and lower limb alignment and ground reaction force (GRF) during one-legged landing movements. Methods: The study subjects were 12 men who performed a one-legged landing movement from a 30-cm platform before and after fatigue tasks, including lower-limb muscle fatigue, cardiopulmonary fatigue, and brain fatigue tasks. For the measurement of joint angles and moments and GRF, a three-dimensional motion analysis device and a floor reaction-force meter were used. Statistics were performed using Wilcoxon''s signed rank sum test as a multiple comparison test with Bonferroni adjustment to compare the difference in effects. Results: The maximum trunk flexion angle during landing on one leg was significantly lower in the brain fatigue group than in the control group. The time to peak vertical GRF (pGRF) was significantly shorter in the leg-muscle fatigue group than in the control group. Conclusion: Brain fatigue may have altered the postural strategy before and after landing, resulting in a decrease in trunk flexion angle. Time to pVGRF was shortened in the leg muscle fatigue group, suggesting that there may be an increased risk of ACL injury. Time to pVGRF during lower extremity muscle fatigue and trunk flexion angle during brain fatigue may be more pronounced during actual sports activities.