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3640 Vswitch: Cisco 3560, Cisco 3750, and Huawei 9306 Switches 2Network Security Device Firewall:Attackers can defend against attacks from the company's internal and external networks. Cisco ASA 5505, 5510, 5520, 5540, 5550, 5580 VPNDevice:Virtual Private channel through the Internet 3And wireless network devices:Wireless Router (TP-LINK), wireless network card, Wireless Bridge 4Network device manufacturer:CiscoCompanies, Huawei companies Vi. Network Topology 1) Star-based topology Advantages:

3640 Vswitch: Cisco 3560, Cisco 3750, and Huawei 9306 Switches 2Network Security Device Firewall:Attackers can defend against attacks from the company's internal and external networks. Cisco ASA 5505, 5510, 5520, 5540, 5550, 5580 VPNDevice:Virtual Private channel through the Internet 3And wireless network devices:Wireless Router (TP-LINK), wireless network card, Wireless Bridge 4Network device manufacturer:CiscoCompanies, Huawei companies Vi. Network Topology 1) Star-based topology Advantages:

that facilitates the handling of programs and hardware, and some common programs that are used by all programsLibrary calls: Encapsulating system callsLiberal callKernel callSystem call(kernel receives requests from other programs)malloc (), free () two system calls requesting memory and freeing memoryPos:portable Operating System POSIXa rule ----- Portable Operating system specification, programs written on different platforms can be compatible with each othercompiling compilation links Execut

(Beginner)Minimal (production environment)8. Installation Attention DetailsALT+CTRL+F2 can be switched to the temporary command line during installationDrawing in Windows: Running MPsNetwork card settings can be automatically obtained or manually set (IP, subnet mask, gateway, DNS)Time setting interface removes "System clock uses UTC current time as GMT"Using a custom partitioning strategyInstalling the KDE environment in desktops9. Install VMware Tools (after downloading VMware Tools, the Cent

1. The computer hardware is based on the operating system, and then the application software. 2. The Python language processes the operating system and then completes hardware usage through the operating system. 3. Memory: data cannot be stored permanently, but the speed is fast. Hard Disk: permanent data storage, but slow 4. The operating system and application software are stored in the hard disk, and some programs of the operating system direct

Computer hardware can actually be more easily divided into CPU + memory +io devices. The three of them are through a bus to exchange data, and you know in the three CPU speed of the fastest, memory second, IO device third, to make the three coordination of communication requires a certain control. 2. our CPU has its own local bus, the same memory, the local bus through the motherboard of the South Bridge chip link together to communicate. North Brid

, sent out by the network card. So the ACK x+2 is the signal to switch the user state to the kernel state. The cache on the client is then cleared.B, the UDP protocol just send, send after the cache (because the cache is occupied by memory), regardless of the object is not present, in case the network is broken, the other side can not receive data, it appears unreliable, so to combine the TCP protocol, TCP has to wait for the other party to confirm the receipt of the message before clearing the

| | _inf = Max |x_i|$General P norm:| | x| | _p = (\sum_{i=1}^n x_i^p) ^1/p$Matrix norm:| | a| | _f = \sqrt{\sum_{i=1}^m \sum_{j = 1}^n a_ij^2 = \sqrt{tr (a^ta)}$The rank of the matrix: $det (AB) = det (BA) $ $det (a^-1) = \frac{1}{\det (A)}$ $det (a^t) = det (A) $ $det (A) = 0$ when and only if $a$ is singular Trace of the Matrix: the and of the diagonal elementsSpecial matrices: Identity matrix: The diagonal element is 0 and the other element is 1 Diagona

1. Start Terminal 1 point Menu "application-attachment-terminal" command, open a terminal window; 2 out of a terminal window, the title bar is their own username and computer name, a cursor in the window flashing a flash, indicating that you can enter the command; ; The above ~ represents its own home folder, $ represents the normal command prompt, and if it is a #, it is the administrator prompt; 2. Common commands 1 ls command, a

Overview of Computer Network Basics Chapter 2 Overview 1. Understand the two main functions that computer networks provide to users: connectivity and sharing. 2. In conjunction with "4.2.1 virtual Interconnect Network" (p110), understand that "the Internet is a network ". 3. Understand the three phases of Internet development. Arpanet, three-level Internet, and m

Python Computer Vision: Chapter 1 Image Processing basics, python Image ProcessingChapter 1 basics of image processing

to group and sort in a query (5) Improve system performance with an optimized stealth device Increase the disadvantage of the index (1) Creating and maintaining indexes is time consuming (2) Index to occupy physical space (3) Indexes should be maintained dynamically when the data in the table is added, deleted, and modified As a general rule: You should create an index on the following columns: (1) On columns that are often searched (2) on the column as the primary key (3) On columns that a

computer is loaded into memory and then handed to the CPU for operation.4. Input device: Data input into the computer (mouse, keyboard, scanner, microphone, camera are input devices. ）5. Output device: Outputs the data (display, printer)6. Communication equipment: Network card (hardware necessary for Internet)Two. Software (consisting of programs and documents). For example, a photo, a resume, a piece of a

Computer Basics: Binary, octal, decimal, hex 2006-11-29 20:23 one or 10 binary number The decimal number is the most widely used counting system in daily life. The symbols that make up the decimal number have a total of 10 symbols such as 0,1,2,3,4,5,6,7,8,9, and we call these symbols digital.In decimal, each digit has a total of 10 0~9, so the base of the count is 10. More than 9 must be repres