试论中国电视全域网络建设

近年来,媒体融合发展动作频频,传统电视媒介的新媒体建设从早期单一的电视网站升级换代为“两微一端一站”的“网台联动”。透过中国电视与新媒体融合发展的全域网络渐进路径,不仅可以看到中国电视与时俱进的创新精神和电视网站品牌的重新定位(涉及名称更改、网站频道变化和信息内容转化),还可看到集电视网站、微信微博、新闻客户端为一体的“中央厨房”式运作管理.更可看到新时代中国电视有所作为有所担当的崭新面貌.以及中国电视从向世界发达国家学习借鉴阶段步入加速前行奋力赶超阶段的壮志豪情和坚实步伐。

网络全域:Cyberspace的概念辨析与思考

通过词源分析和背景介绍,从军事、物理学和社会学等角度给出对Cyberspace的内涵与特征的理解,在定义了Cyberspace概念的基础上,给出"网络全域"的译名及其考量因素。

Secure Authentication of WLAN Based on Elliptic Curve Cryptosystem

The security of wireless local area network （WI.AN） becomes a bottleneck for its further applications. At present, many standard organizations and manufacturers of WLAN try to solve this problem. However, owing to the serious secure leak in IEEES02.11 standards, it is impossible to utterly solve the problem by simply adding some remedies. Based on the analysis on the security mechanism of WLAN and the latest techniques of WI.AN security, a solution to WLAN security was presented. The solution makes preparation for the further combination of WLAN and Internet.

AUTHENTICATED SYMMETRIC-KEY ESTABLISHMENT FOR MEDICAL BODY SENSOR NETWORKS

This study concerns security issues of the emerging Wireless Body Sensor Network (WBSN) formed by biomedical sensors worn on or implanted in the human body for mobile healthcare appli-cations. A novel authenticated symmetric-key establishment scheme is proposed for WBSN,which fully exploits the physiological features obtained by network entities via the body channel available in WBSN but not other wireless networks. The self-defined Intrinsic Shared Secret (ISS) is used to replace the pre-deployment of secrets among network entities,which thus eliminates centralized services or au-thorities essential in existing protocols,and resolves the key transport problem in the pure symmet-ric-key cryptosystem for WBSN as well. The security properties of the proposed scheme are demon-strated in terms of its attack complexity and the types of attacks it can resist. Besides,the scheme can be implemented under a light-weight way in WBSN systems. Due to the importance of the ISS concept,the analysis on using false acceptance/false rejection method to evaluate the performance of ISS for its usage in the scheme is also demonstrated.

Prediction of Instability Separation Modes and Its Application in Practical Dynamic Security Region

The transient critical boundary of dynamic security region (DSR) can be approximated by a few hyper planes correlated with instability separation modes. A method to fast predict instability separation modes is proposed for DSR calculation in power injection space. The method identifies coherent generation groups by the developed K-medoids algorithm, taking a similarity matrix derived from the reachability Grammian as the index. As an experimental result, reachability Grammian matrices under local injections are approximately invariant. It indicates that the generator coherency identifications are nearly consistent for different injections. Then instability separation modes can be predicted at the normal operating point, while average initial acceleration is considered as the measure of the critical generator group to amend the error. Moreover, based on these predicted instability separation modes, a critical point search strategy for DSR calculation is illustrated in the reduced injection space of the critical generators. The proposed method was evaluated using New England Test System, and the computation accuracy and speed in determining the practical DSR were improved.

Research and Implementation of inter-VLAN communication

In order to reduce broadcast storms, improve network security, virtual LAN technology has been widely used in LAN planning. But in many networks, it was be required that computers in different VLAN （Virtual Local Area Network） could be communicated. This article mainly introduced the VLAN classification method inter-VLAN data communication technology, and explained in detail with two simple examples the concrete configure method of the communication between the same cross-switch VLAN traffic and inter-VLAN.