信息安全专业科技英语

1)A hacker is someone who creates and modifies computer software and computer hardware,including computer programming,administration,and security-related items,In computer programming,a hacker is a softwere designer and computer who builds elegant,beautiful programs and systems.2)Attrack is an assault against a computer system or network as a result of deliberate,intelligent action;for example,denial of service attacks,penetration and sabotage,Such as brute force attack,dictionary attack,denial of service attack,replay attack,piggybacking,penetration and sabotage.3)Although the activities of the blackhat hacker can be seen as a single shot in the night,the script kiddies scan will appear as a series of shotgun blasts,as their activity will be loud and detectable. 4)Privilege escalation can best be described as the act of leveraging a bug or vulnerability in an application or operating system to gain access to resources that normally would have been protected from an average user.5)Network Scanning is the use of a computer network for gathering information on computer systems,which may be used for system maintenance,security assessment and investigation,and for attack.1)最初的黑客是指具有熟练的编写和调试计算机程序的技巧，并使用这些技巧来获得非法或未授权的网络或文件访问，入侵企业内部网的人。

随着各种强大的黑客工具的广泛传播，对计算机技术了解很少的人也可以实施黑客攻击行为，因此网络系统受到黑客攻击的可能性大大增加了。

2）主动攻击会造成网络系统状态和服务的改变。

主动攻击包括试图阻断或攻破保护机制、引入恶意代码、偷窃或篡改信息。

主动攻击可能造成数据资料的泄露和散播，或导致拒绝服务以及数据的篡改，包括大多数的未授权用户企图以非正常手段和正常手段进入远程系统。

3）一般完整的攻击过程都是先隐藏自身，在隐藏好自己后在进行预攻击探测，检测目标机器的各种属性和具备的被攻击条件；然后采取相应的攻击方法进行破坏，达到自己的母的之后攻击者会删除自己的行为在目标系统中的日志。

4）缓冲区溢出攻击已成为目前较为主流的攻击方法，但缓冲区溢出的类型有多种，有针对操作系统的溢出，如windows rpc dcom溢出、windows lsass.dll溢出等；也有针对应用服务的溢出，如IIS SSL PCT溢出、SERV-U mdtm溢出、Exchange Server NNTP溢出等。

5）拒绝服务（Denial of servive，简称DoS攻击），就是通过非法独占受攻击的目标系统的服务，最终试图阻止合法用户使用受攻击目标提供的网络服务。

拒绝服务攻击最常见的就是攻击者通过产生大量流向受害网络的数据包，消耗该网络所有的可用宽带。

1)Until modern times,cryptography referred almost exclusively to encryption,the process of converting ordinary information(plaintext)into something unintelligible;this is a ciphertext.Decryption is the reserve,moving from unintelligible ciphertext to plaintext.2)In cryptography,a cryptographic hash function is a hash funtion with certain additional security properties to make it suitable for use as a primitive in various information security applications,such as authentication and message integrity.3)Before the modern era,cryptography was concerned solely with message confidentiality(i.e,encryption)-conversion of messages from a comprehensible form into an incomprehensoble one,and back again at the other end,rendering it unreadable by interceptors or eavesdroppers without secret knowledge (namely,the key needed for decryption).4)Symmetric-key cryptography refers to encryption methods in which both the sender and receiver share the same key(or,less commonly,in which their keys are different,but related in aneasily computable way).5)In addition to encryption ,pubblic-key cryptography can be used to implement digital signature schemes.A digital signature is reminiscent of an ordinary signature;they both have the characteristic that they are easy for a user to produce,but difficult for anyone else to forge.1)现代密码学的一个基本原则是：一切秘密都会存在于密钥之中。

其含义是，再设计加密系统时，总是假设密码算法是公开的，真正保密的是密钥。

这是因为密码算法相对密钥来说更容易泄露。

2）对称密码体制的密码需要实现经过安全的密码通道由发方传给收方。

这种密码体制的优点是：安全性高，加密速度快。

缺点是：随着网络规模的扩大，密钥的管理成为一个难点；无法解决消息确认问题；缺乏自动检测密钥泄露的能力。

3）密码协议具有以下特点：协议自始至终是有程序的过程，每一个步骤必须执行，在前一步没有执行完之前，后面的步骤不可能执行；协议至少需要两个参与者；通过协议必须能完成某项任务；协议必须满足一定的安全需求。

4）由于密码学为通信提供强大的安全性，攻击这把目光转向了系统漏洞。

系统漏洞是软件系统、网络协议等在设计编写时出现的安全缺陷，攻击者可以利用这些漏洞对系统进行攻击。

对于这类攻击，目前有多种不同的应对技术，而密码学也是在一定程度上可以发挥作用。

5）公开密钥密码也称为非对称密钥密码。

使用公开密钥密码的每一个用户都分别拥有两个密钥：加密密钥和解密密钥，它们两个并不相同，并且由加密密钥得到解密密钥在计算机上是可行的。

每一个用户的加密密钥都是公开的（因此，加密密钥也称为公开密钥）1)A firewall sits at the junction point or gateway between the two networks,usually a private network and a public network such as the Internet.the earliest firewalls were simply routers.2)Professional firewall products catch network packet before the operating system does ,thus, there is no direct path from the internet to the operating system's TCP/IP stack.3)Circuit level gateways work at the session layer of the OSI model,or the TCP layer of TCP/IP. They monitor TCP handshaling between packets to determine whether a reuested session is rmation passed to remote computer thought a circuit level gateway appears to have originated from the gateway.4)Stateful multilayer inspection firewalls combine the aspects of the other three types of firewalls.they filter packets at the network layer ,determine whether session packets are legitimate and evaluate contents of packets at the application layer .5)Whereas a dual-homed host architecture provides services from a host that's attached to multiple networks(but has routing turned off),a screened host architecture provides services from a host that's attached to only the internal network,using a separate router.1)如果对Internet的往返访问都通过防火墙，那么，防火墙可以记录各次访问，并提供有关网络使用率的有价值的统计数字。