Packet Relay Server

We usually have more contact with "hard" routes in our daily lives. 　　The so-called hard routing is a special application of hardware devices, including processors, power supply, embedded software, to provide the configured router function. 　　"Soft" routing is relative to "hard" routing, refers to the use of professional servers, with the free Linux/unix platform or professional Windows platform set up. "Soft" Routing has many advantages: first, should ...

Why use a VLAN? The implementation of VLAN is a logical division of users, so that users in different VLANs can not communicate directly. This technology facilitates implementation and saves money. However, with the application of VLAN more and more wide, and VLAN-related security management problems are more and more serious. The application of VLAN technology provides a strategy method based on management mode for network security, we can choose different VLAN partition methods according to the characteristics of enterprise network management. Although the network security to a certain extent has been guaranteed, but ...

"51cto.com exclusive translation" Content filtering proxy server to help administrators control the content delivery process of Internet access, it is often used in institutions, schools to ensure that the use of the Internet is consistent with their own use of the policy, content filtering agents must be for the Internet access rights and cross-enterprise constraints for fine-grained adjustment. Content filtering agents can be used to filter unwanted content, using such methods as URL or DNS blacklist, URL filtering, MIME filtering, keyword filtering, cookie filtering, packet header filtering, pornographic image filtering, etc. Content filtering agent support authentication, ...

First, Nat/alg way ordinary NAT is to modify the UDP or TCP message header address information to achieve address conversion, but for VoIP applications, in the UDP net load also need to take address information, ALG means that in the private network of VoIP terminals in the net load to fill in the private network address, This address information is modified to an external address on Nat via Nat. The recognition of voice and video protocols (H323, SIP, mgcp/h248) and the control of Nat/firewall, and each additional new application will require ...

First, ping it is used to check whether the network is smooth or network connection Speed command. As an administrator or hacker living on the web, the ping command is the first DOS command that must be mastered, which uses the principle that the machine on the network has a unique IP address, we send a packet to the destination IP address, and the other side returns a packet of the same size, According to the returned packets we can determine the target host's existence, can initially judge the target host's operating system and so on. Let's take a look at some of its common operations. First look at the help ...

For small and medium-sized enterprises, there are many free and open source router and firewall solutions, even as a business choice. 　　Many of these products offer LAN services, such as VPN services, hotspot gateways, and the use of mandatory network portals to share wireless networks. Here, the editors find open source and free router projects that are suitable for businesses that include small businesses, midsize, and even the size of Cisco and Juniper.  Gossip Less, we look at these seven open source and free Linux network operating system. &nb ...

With the continuous expansion of data network bandwidth, hundreds of megabytes or even gigabit to the desktop has become possible. The increase in bandwidth also provides a powerful prerequisite for transmitting voice over the data network. At the same time, VoIP technology is increasingly mature, similar to voice compression, QoS quality assurance, such as the topic has been widely discussed and reached a consensus. It can be said that VoIP technology has been from the original experimental nature of the real specificity for the mature commercial applications. With the continuous expansion of data network bandwidth, hundreds of megabytes or even gigabit to the desktop has become possible. The increase in bandwidth also provides a powerful prerequisite for transmitting voice over a data network.

"TechWeb Report" September 11 News, 2012 China Internet Conference will be held in Beijing International Conference Center today. 　　Hequan, academician of Chinese Academy of Engineering, said that China's mobile internet traffic has increased 10 times times over the past 18 months, accounting for 10% of the global Internet traffic, and the bandwidth traffic of our country's access has increased by 6 times times in the last 5 years. The following is a transcript of the speech: Hequan: Respecting leaders, experts, distinguished guests, good morning, very happy to have the opportunity to come to this meeting, my report topic is "Internet from fixed to mobile change", will say four aspects ...

Summary: The threat of information security is quite extensive, hacking, server or employee computer malware infection, confidential data stolen, but only a few common ways, however, the current enterprise it in day-to-day operations, more fear but also may be the threat of information security on the face of a wide range of hackers, Server or employee computers are infected with malware, confidential data is stolen, but only a few of the common way, however, the current enterprise it in day-to-day operations, the more fear but also can often face the threat is distributed service blocking attacks (DDoS), because ...

The threat of information security is quite extensive, hacking, server or employee computer malware infection, confidential data theft is only a few of the common ways, however, the current enterprise it in day-to-day operations, the more fear but also can often face the threat is distributed service blocking attacks (DDoS), Because once your external network, application server suffers from such attacks, it will not function properly. It is recommended that the webmaster use the DNS service provided by domestic professional services, such as Dnsdun, to ensure the stability of the site analysis. DDoS attacks are not these ...