[MEIMAN transfer] Mobile IP wins DHCP In the access technology of wireless local area networks, DHCP is currently widely used, but there are still some deficiencies in terms of security, manageability, and mobility. Recently, a Mobile IP technology has emerged. Can it solve the defects of DHCP and become the new favorite of wireless LAN applications? A PON consists of an Optical Line Termination (OLT) at the communication company's office and a number of Optical Network Units (ONUs) near end users. Typically, up to 32 ONUs can be connected to an OLT. The passive simply describes the fact that optical transmission has no power requirements or active electronic parts once the signal is going through the network. Passive Optical Network(PON Series) Passive Optical Network,GPON Technology,PON Network ,PON Series Shenzhen N-net High-Tech Co.,Ltd , http://www.nnetswitch.com
At present, China's major network operators are in full swing to build their own wireless network platforms, respectively in their respective spheres of influence to take advantage of the market opportunities. Operators have successively opened wireless network access services in hot spots of many developed cities, such as airports, hotels, and business districts of high-end office buildings, which greatly facilitates users' access to the Internet network.
However, at present, this kind of wireless network access is basically solved through DHCP, and users need to rent a temporary IP address to log in to the network normally. Assuming that the user leaves this place to go to another area, he can only apply for another temporary IP address. Such frequent application and rental increase the burden on users. Users hope that their network IP can also be like a mobile phone number-"one IP travels across the country."
The advent of Mobile IP technology and the advent of the Mobile IP system can meet this demand of users. Whether users are in the airport, hotel, or in the business area of ​​each office building, using a unique network IP address to access the network, you can completely and truly achieve full network roaming.
Another important point is that users can continue to use the IP address of the original office network after one application. In this way, users can not only log on to the Internet, but also log on to their own office network to achieve mobile office. At the same time, because the Mobile IP system supports two-way access, other "network neighbors" of the user's original office network can still communicate with the user normally. In other words, the mobile IP system not only allows users to log in to the Internet, but also enables users to log in to their original intranet (Intranet) and realize two-way network communication.
The following compares the functional characteristics of DHCP and Mobile IP.
(1) DHCP
DHCP is a more common access method in the current WLAN network environment. It greatly simplifies the IP address allocation and management of network administrators, and can provide the configuration of the user's default gateway and DNS server. But it also has the following inherent drawbacks:
â— Poor security: Basically, there are no strict verification measures, and users can easily access the network, which poses potential security risks to the network.
â— Poor management: Since IP addresses are randomly assigned to users, it is difficult to manage users.
â— One-way access: Users can only access servers and nodes on the Internet in one direction.
â— Cannot move: DHCP can solve the network access problem, and does not provide the mobile roaming function of network equipment.
(2) Mobile IP
Mobile IP is a computer network communication protocol, it can ensure that the computer does not change the existing network IP address, does not interrupt the ongoing network communication and does not interrupt the network application being executed during the movement of the computer Uninterrupted access.
Mobile IP technology can solve the shortcomings that TCP / IPv4 does not support mobile roaming of network terminals. Mobile IP system is usually composed of Mobile IP server and mobile IP client software. Mobile IP technology is a value-added service that does not have any special requirements for network equipment and topology. Moreover, Mobile IP supports both wired and wireless network environments. Compared with DHCP technology, Mobile IP has the following advantages:
â— Support mobile: users can access their local area network in different network segments to achieve mobile and remote office.
â— Good security: assign a password to each user, so that the network access device can be filtered to prevent illegal users from accessing randomly.
â— Access authentication: When users use the mobile IP function, they need to perform a login authentication process on the mobile IP server to access the network. This process is automatically completed by the system without user intervention.
â— Convenient management: Since each user is assigned a fixed IP address, users can be managed based on the IP address.
â— Two-way access: Users who travel to other places can not only actively access servers and nodes in the Internet, but also can be accessed by other network devices in real time.
â— Secure tunnel: When using mobile IP technology, a two-way tunnel is established between mobile IP servers to realize the secure transmission of user data.
N-NET supply Ethernet Passive Optical Network (EPON) and Gigabit-Capable Passive Optical Network(GPON),EPON and GPON are popular versions of passive optical networks (PONs). All PON systems have essentially the same theoretical capacity at the optical level. The limits on upstream and downstream bandwidth are set by the electrical overlay, the protocol used to allocate the capacity and manage the connection.