基于VMWare的IPSec综合实验设计

IPSec是互联网的基础安全协议。建立IPSec安全通道之前,对等体之间需要进行身份认证。IPSec身份认证的传统实验是通过"预共享密钥"的方式来进行的。设计了两个更通用的IPSec身份认证实验:"基于证书"和"基于Kerberos协议"。而基于虚拟机平台的实验具有更方便、更经济的优点。此外,本实验还涉及到了Windows平台上各种安全设置,如活动目录、DNS服务器、DHCP服务器,防火墙、证书颁发中心CA等,具有很强的综合性。     

NTT DoCoMo公司FOMA模式的生态观透视

日本NTT DoCoMo的FOMA在推出之时和运动之初，实际上处于一个各“物种”进化不同步，貌似成熟的生态系统，各个角色之间难以沟通协调，导致业务和用户增长缓慢。从2003年开始，该公司针对生态系统中的“短板”，二次发力，进行积极的投入和协调，促进了FOMA短期内的迅速发展。     

PHS发展及其WLL应用

１９９６年１２月，笔者随黑龙江省邮电管理局新技术考察团在日本与富士通公司进行了多方面的技术交流，并就今后双方合作的有关事宜进行了深入探讨。本文产将就此次考察的主要内容之一ＰＨＳ及其ＷＬＬ应用作一介绍。     

本地信任SSL代理增强Web电子交易安全

由于标准浏览器中的内嵌SSL安全模块不受终端用户控制，并且，该SSL安全模块所能提供的最大安全性还受到国外安全产品出口限制的影响，致使单纯的基于标准浏览器的端到端SSL连接并不适合于安全性要求较高的Web电子交易场合。本文设计并实现了一种本地信任SSL代理，将原先端到端的SSL连接拆分成两个独立的SSL连接，即从浏览器到本地信任SSL代理的本地SSL连接以及从本地信任SSL代理到远端安全Web服务器的远程SSL连接。由于远程SSL连接独立于标准浏览器，并可根据用户需要选择安全性更高的加密算法和密钥长度，因而，能够有效增强现有Web电子交易平台的安全性。     

Design and implementation of IPv6 oriented security mechanisms of port control protocol and peer-to-peer communication

Recently, the number of personal intelligent equipment increases rapidly which makes the internet protocol version 6 (IPv6) transition more imperative. Port control protocol (PCP) is one of the important IPv4-in-IPv6 tunnel technologies. Meanwhile, with the increasing demand to communicate or share files between terminal equipment, it is necessary to realize the peer to peer communication to support the transmission of data directly between the terminal equipment without a third-party server. In this paper, the structure of user access network and the deployment of the IPv6 transition technology based on IPv4-in-IPv6 tunnel are analyzed comprehensively, based on which the internet protocol security (IPSec) solution is chosen to protect the security of PCP message and the transport layer security (TLS) solution is chosen to protect the security of the peer-to-peer communications. A system for the authorization and distribution of digital certificates is designed for the TLS solution. Finally, the open source software Openswan is used to implement the IPSec solution, and the open source software OpenSSL is used to implement the TLS solution.     

The competitiveness of U.S. manufacturers in the global market for fiber optics

U.S. manufacturers of fiber optic equipment continue to be major competitors in the world markets for these products. U.S. producers account for approximately half of the total worldwide production of optical fiber and cable. In active components for fiber optic transmission systems (transmitters, receivers, amplifiers, and related components), U.S. firms are beginning to recapture some of the market share previously lost to foreign competitors. This article provides a brief overview of the competitiveness of U.S. manufacturers in the global market for fiber optic equipment, with particular focus on European and Japanese competitors.     

新纯铝光谱块状标样的研制

本文叙述了含Ｇａ等９个元素的新纯铝光谱块状标样的研制过程。研制出的标样具有工艺先进、化学成分均匀、定值准确及校准曲线啮合系数高等特点。通过试用分析，用本套标样分析的结果与化学仲裁分析结果相符。本套标样研制成功，填补了含Ｇａ吕块状光谱标样的空白，满足了贯彻１９９３年国家颁布的新的《重熔用铝锭》标准对光谱分析用标样的急需。     

Quasi-two-dimensional magnetic properties of an organic ion-radical salt: 3,3′-diethyl-2,2′-selenacyanine-[TCNQ]2

The temperature dependence of the electric conductivity, the spin-susceptibility and the ESR linewidth of an organic ion-radical salt, 3,3′-diethyl-2,2′-selenacyanine-[TCNQ]₂, was measured to elucidate the quasi-two-dimensional magnetic properties of the salt.     

A Raman spectral analysis of the ammonium iodide—dioxane complex

The solid state complex between ammonium iodide and 1,4-dioxane has been found by TGA studies to be a ($\text{1}\text{1}$) adduct rather than a ($\text{1}\text{2}$) adduct as previously formulated. The laser Raman spectra of NH₄I· dioxane and ND₄I· dioxane in the N-H and N-D stretching regions show decreases in frequency compared to NH₄I and ND₄I which are consistent with hydrogen bonding of the N-H · O variety as a means of incorporation of the dioxane into the salt crystal lattice.     

Crystal structure and habit of fine metal particles formed by gas-evaporation technique; bcc metals (V,Fe, Cr,Mo and W)

Fine particles of several kinds of bcc metals were prepared by evaporation in an argon atmosphere. They were collected at various growth zones in the smokes and their structures and habits were studied by electron microscopy. Vanadium and iron particles grown in all zones have the ordinary bcc structure. However, chromium and molybdenum particles grown in the inner part of the smokes have the bcc structure, and those in the outer part have the A-15 type structure. Habits of particles with the bcc structure can be generally described in terms of rhombic dodecahedra truncated by six (100) faces with various degrees of truncation from 0 to 100%. The truncated rhombic dodecahedron is a common habit to the bcc metals, though the degree of truncation is dependent on the metal. For vanadium it varies from zone to zone systematically. Molybdenum particles of rounded cube and {211} icositetrahedron are found to have the A-15 type structure in addition to the well known {211} icositetrahedron and rhombic dodecahedron found in chromium.