【正文】 es all outside access by default. W hen first installed, no one can access the pany’s LAN, unless the administrator enables , FTP and Web access for remote users. Unlike ON Guard, which uses SMLI, The Wall is an application level firewall that uses proxy servers to protect the work from the Inter. These firewalls have two work adapters to provide a shield. One connects to your LA N, and the other to a 濱州學(xué)院畢業(yè)設(shè)計(jì) (專業(yè)外文翻譯 ) 9 router or other Inter connection. Server Security Web Stalker Pro Web Stalker Pro resides on the web server and protects the data stored from both local users and outside intruders. It does so by letting the pany set protection policies. For example, it shuts down your web server in case an intruder tries to access protected data. Web Stalker Pro also has excellent reporting capabilities, but its primary function is detection and response. It can’t always prevent people from accessing the data on a web server, but it can alert if they do. For added security, it is advisable to use a firewall in conjunction with Web Stalker. Web Stalker Pro runs on Windows NT and as an NT service and works with Microsoft’s Inter Information Server (IIS) and Netscape Web servers. It relies on Windows NT’s audit trails and event logs to alert it when a hacker has attempted to access protected data. The audit trails and event logs track everything, but they only show the series of events leading up to an intruder’s entry. Careers in Inter Security In short supply and in high demand, systems administrators are prospering. The strong demand for system and security managers has forced salary increases to 15 percent in 1997. Surveys show that close to 1,600 system and security administrators are responsible for the care of electronic merce systems, Web servers, enterprise systems and puters used in advanced scientific research. According to the survey, salaries in New York, Boston, San Francisco and San Jose are the highest, but salaries are increasing all across the US, Canada, Europe, and Asia. Of those Administrators who were surveyed, salaries ranged between $50,000 and $59,999 with an average of $57,346. The greatest salary increase was for employees earning $70,000 to $79,999 with an annual average increase of 14 percent. The highest salaries ($70,846) were those in research panies with fewer than ten 濱州學(xué)院畢業(yè)設(shè)計(jì) (專業(yè)外文翻譯 ) 10 employees, followed by systems integrators ($70,230) working at firms with 11 to 100 employees. Lowest salaries reported were in education, ranging from $43, 933 to $47,262. Typically a job posting describes the tasks and skills needed to excel in this field as such: Qualifications: BA /BS degree in Information Systems, puter science or business related fields. Selfmotivated, good munications skills and enthusiasm for pursuing a career in Information Systems. 濱州學(xué)院畢業(yè)設(shè)計(jì) (專業(yè)外文翻譯 ) 11 互聯(lián)網(wǎng)安全 一個有著良好背景但懷著惡意意圖的入侵者，有很多方式通過互聯(lián)網(wǎng)滲透到公司內(nèi)部系統(tǒng)和網(wǎng)絡(luò)設(shè)備。 applications that run on a server with two work connections, acting as a server to the application client and as a client to the application server. Application gateways evaluate work packets for valid specific data making the proxies more secure than packet filtering. Most applicationgateway firewalls also have a feature called work address translation that prevents internal IP addresses from appearing to users outside the trusted work. There are two primary disadvantages to application gateways. The first disadvantage is a performance decline caused by the proxy function’s double processing. Another is the lag time for the firewall vendor to supply an application proxy for a newly introduced Inter service, such as Real Audio. 3） SOCKS firewall Another type of applicationproxy firewall is the SOCKS firewall. Where normal applicationproxy firewalls do not require modifications to work clients, SOCKS firewalls require specially modified work clients. This means users have to modify every system on their internal work that needs to municate with the external work. On a Windows or OS/2 system, this can be as easy as swapping a few DLLs. In cases where performance is concerned, organizations using application gateways should not be worried with a 10Mbps Ether or 100Mbps Fast Ether connection. If panies use application proxies within their work, they can consider fast hardwarebased solutions such as Cisco’s PIX Firewall or Seattle Software’s Firebox. The pany may also consider installing firewall software on a system with multiple processors. Major firewall vendors have incorporated additional security technologies into their firewall products and partnered with other security vendors to offer plete Inter security solutions. These additional features will be discussed subsequently in this article and include encryption, authentication and protection from malicious Java and ActiveX downloads. 濱州學(xué)院畢業(yè)設(shè)計(jì) (專業(yè)外文翻譯 ) 4 3. Authentication Firewalls do their authentication using IP addresses, which can be faked. If a pany wants to give certain users access over the Inter to sensitive internal files and data, they will want to make sure to authenticate each user. Authentication simply describes the numerous meth