计算机网络安全(2)

原作者:不详添加时间:2007-07-12 原文发表:2007-07-12 人气:60 来源：互联网

本文章共5877字，分3页，当前第2页，快速翻页：

-----------------------------------------------------------------------------------------------------------------------------------------------

本文提示：《计算机网络安全(2)》是本站编辑们为广大网友精选的实用文章，本文阐述了关于文章的相关理论，相对来说专业性强，但是本文只是针对于某个问题提出的见解与论述，未必能辐射到相关问题的方方面面，所以本文处理问题的方法仅仅为您提供一些参考。更多问题请查阅学习中国网其他栏目哦.

-----------------------------------------------------------------------------------------------------------------------------------------------

technology
this section provides a basic introduction to the technologies that underlie the internet. it was written with the novice end-user in mind and is not intended to be a comprehensive survey of all internet-based technologies. subsections provide a short overview of each topic. this section is a basic primer on the relevant technologies. for those who desire a deeper understanding of the concepts covered here, we include links to additional information.

what does broadband mean?
"broadband" is the general term used to refer to high-speed network connections. in this context, internet connections via cable modem and digital subscriber line (dsl) are frequently referred to as broadband internet connections. "bandwidth" is the term used to describe the relative speed of a network connection -- for example, most current dial-up modems can support a bandwidth of 56 kbps (thousand bits per second). there is no set bandwidth threshold required for a connection to be referred to as "broadband", but it is typical for connections in excess of 1 megabit per second (mbps) to be so named.

what is cable modem access?
a cable modem allows a single computer (or network of computers) to connect to the internet via the cable tv network. the cable modem usually has an ethernet lan (local area network) connection to the computer, and is capable of speeds in excess of 5 mbps.

typical speeds tend to be lower than the maximum, however, since cable providers turn entire neighborhoods into lans which share the same bandwidth. because of this "shared-medium" topology, cable modem users may experience somewhat slower network access during periods of peak demand, and may be more susceptible to risks such as packet sniffing and unprotected windows shares than users with other types of connectivity. (see the "computer security risks to home users" section of this document.)

what is dsl access?
digital subscriber line (dsl) internet connectivity, unlike cable modem-based service, provides the user with dedicated bandwidth. however, the maximum bandwidth available to dsl users is usually lower than the maximum cable modem rate because of differences in their respective network technologies. also, the "dedicated bandwidth" is only dedicated between your home and the dsl provider's central office -- the providers offer little or no guarantee of bandwidth all the way across the internet.

dsl access is not as susceptible to packet sniffing as cable modem access, but many of the other security risks we'll cover apply to both dsl and cable modem access. (see the "computer security risks to home users" section of this document.)

how are broadband services different from traditional dial-up services? www.xuexi86.com
traditional dial-up internet services are sometimes referred to as "dial-on-demand" services. that is, your computer only connects to the internet when it has something to send, such as email or a request to load a web page. once there is no more data to be sent, or after a certain amount of idle time, the computer disconnects the call. also, in most cases each call connects to a pool of modems at the isp, and since the modem ip addresses are dynamically assigned, your computer is usually assigned a different ip address on each call. as a result, it is more difficult (not impossible, just difficult) for an attacker to take advantage of vulnerable network services to take control of your computer.

本文章更多内容：<<上一页 - 1 - 2 - 3 - 下一页>>

本页地址