Моя феноменально стена by Shady Amanbay https://padlet.com/amanbayshady1/l77o104xegh2 Сделано с любопытством en-us 2018-01-30 05:29:21 UTC 2025-12-20 18:12:28 UTC hello@padlet.com HTTPS (Hyper Text Transfer Protocol Secure) https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942877 HTTPS is the secure version of HTTP. 
It means all communications between your browser and the website are encrypted. 
HTTPS takes the HTTP protocol, and simply layers a SSL/TLS encryption layer on top of it. 
The SSL/TLS layers has 2 main purposes:
  • Verifying that you are talking directly to the server that you think you are talking to
  • Ensuring that only the server can read what you send it and only you can read what it sends back.
How does HTTPS Work?

HTTPS pages use one of two secure protocols to encrypt communications - SSL (Secure Sockets Layer) or TLS (Transport Layer Security). Both of them use asymmetric system which uses two 'keys' to encrypt communications, a 'public' key and a 'private' key. Anything encrypted with the public key can only be decrypted by the private key and vice-versa.

  1. Hello - The handshake begins with the client sending a ClientHello message (contains the various cipher suites and maximum SSL version that it supports). The server responds with a ServerHello (decision based on the client’s preferences about which cipher suite and version of SSL will be used).

  2. Certificate Exchange - Now that contact has been established, the server has to prove its identity to the client. This is achieved using its SSL certificate, which is a very tiny bit. An SSL certificate contains data, including the name of the owner, the property (eg. domain) it is attached to, the certificate’s public key, the digital signature and information about the certificate’s validity dates. The client checks that it either implicitly trusts the certificate, or that it is verified and trusted by one of several Certificate Authorities (CAs) that it also implicitly trusts. 

  3. Key Exchange - The encryption of the actual message data exchanged by the client and server will be done using a assymmetric algorithm. A process  is accomplished securely using asymmetric encryption and the server’s public/private keys.
]]> 2018-01-30 05:31:32 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942877 FTP irmaler9 https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942903
File Transfer Protocol

a protocol for uploading and downloading files, usually those that are too big and would take too long to download via a regular email program as an attachment.

Here's how it all goes down:
  • A person runs an FTP client application on one computer.
  • Another computer runs an FTP server program. That might be as an "ftpd" (FTP daemon) on a UNIX/Linux computer.
  • It could also be an FTP service on other platforms.

Here's what File Transfer Protocol can do:
  • Transfer files between computers.
  • Create directories.
  • Remove directories.
  • List files.

Adv:
  • Fast, trustworthy, paperless.
  • Send multiple file directories at the same time 
  • Create multiple levels of access 

Disadv:
  • Recursive changes are very hard to make 
  • Not a secure data transfer due to lack of encryption; must use secure alternative such as SFTP 
  • expensive own server

]]> 2018-01-30 05:31:49 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942903 HTTP (Hypertext Transfer Protocol) https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942917 HTTP is the application-level protocol that is used to transfer data on the Web.
HTTP comprises the rules by which Web browsers and servers exchange information. 
HTTP resources are identified and located on the network by Uniform Resource Locators (URLs), using the Uniform Resource Identifiers (URI's) schemes http and https. URIs and hyperlinks in HTML documents form inter-linked hypertext documents.
How does HTTP Work?
An HTTP client initiates a request by establishing a Transmission Control Protocol (TCP) connection to a particular port on a server (typically port 80, port 8080). An HTTP server listening on that port waits for a client's request message. Upon receiving the request, the server sends back a status line, such as "HTTP/1.1 200 OK", and a message of its own. The body of this message is typically the requested resource, although an error message or other information may also be returned. 

]]> 2018-01-30 05:31:59 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942917 POP3 seidolla30_04_99 https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942919 POP3 (Post Office Protocol 3) is the most recent version of a standard protocol for receiving e-mail. POP3 is a client/server protocol in which e-mail is received and held for you by your Internet server.
How does it work?
In the simplest implementations of POP3, the server really does maintain a collection of text files -- one for each e-mail account. When a message arrives, the POP3 server simply appends it to the bottom of the recipient's file.

When you check your e-mail, your e-mail client connects to the POP3 server using port 110. The POP3 server requires an account name and a password. Once you've logged in, the POP3 server opens your text file and allows you to access it. Like the SMTP server, the POP3 server understands a very simple set of text commands. Here are the most common commands:

  • USER - enter your user ID
  • PASS - enter your password
  • QUIT - quit the POP3 server
  • LIST - list the messages and their size
  • RETR - retrieve a message, pass it a message number
  • DELE - delete a message, pass it a message number
  • TOP - show the top x lines of a message, pass it a message number and the number of lines
Your e-mail client connects to the POP3 server and issues a series of commands to bring copies of your e-mail messages to your local machine. Generally, it will then delete the messages from the server (unless you've told the e-mail client not to).

You can see that the POP3 server simply acts as an interface between the e-mail client and the text file containing your messages. And again, you can see that the POP3 server is extremely simple. You can connect to it through telnet at port 110 and issue the commands yourself if you would like to (see How Web Servers Work for details on telnetting to servers).

+
* A local copy of your email.
* Very little remote server storage space overhead required (if emails are deleted from the server as they are retrieved).
* Consolidation of many email accounts and servers to deliver to one inbox.
-
* No remote copy (if emails are deleted from the server as they are retrieved)
* No remote web access or synchronization between several programs or devices.
* All mail is stored in one (and only one) place.
* Local copies of messages still requires disk space to store messages.
* Local copies of messages are vulnerable to data loss or security threats.



]]> 2018-01-30 05:31:59 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942919 Telnet irmaler9 https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942938 TELetype NETwork is a user command and an underlying TCP/IP protocol for accessing remote computers.  Through Telnet, an administrator or another user can access someone else's computer remotely. On the Web, HTTP and FTP protocols allow you to request specific files from remote computers, but not to actually be logged on as a user of that computer. With Telnet, you log on as a regular user with whatever privileges you may have been granted to the specific application and data on that computer.
The Telnet Protocol
The Telnet protocol is designed to provide a bi-directional, eight-bit byte oriented communications facility to allow for a a standard method of interfacing terminal devices and processes.

How does it work?
Telnet uses 23/TCP;
software installed on your computer, to create a connection with the remote host. The Telnet client (software), at your command, will send a request to the Telnet server (remote host). The server will reply asking for a user name and password. If accepted, the Telnet client will establish a connection to the host, thus making your computer a virtual terminal and allowing you complete access to the host's computer.
enables you to control the server and communicate with other servers on the network.  Telnet is a common way to remotely control Web servers.

 
]]> 2018-01-30 05:32:08 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942938 IMAP seidolla30_04_99 https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942959 IMAP ( Internet Message Access Protocol ), as well as POP3, is used to receive e-mail messages to the local client, however, it has a significant difference - only email message headers are downloaded, the text of the message remains on the server. This communication protocol works in two directions, if changes occur on the local client, they are transferred to the server. Recently, IMAP has become more popular, because such giants-providers of e-mail services, like Gmail, began to recommend using it instead of POP3.

IMAP ports are by default the following:

Port 143 - port without encryption Port 993 - SSL / TLS port, also known as IMAPS
How does it works?
First, the client and the server should make handshaking, then the client sends data to the server and waits for a response. At the end of the session, the channel closes. An interesting feature of the IMAP protocol is that the server does not have to respond to commands in turn. That is, while waiting for a response to a request, the client can continue to send requests. The server will respond to them in order, processing requests simultaneously.
Advantage
  •  Synchronization 
  •  not required downloading 
Disadvantages
  •  Performance and Maintenance 

]]> 2018-01-30 05:32:22 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942959 SMTP seidolla30_04_99 https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942990  Simple Mail Transfer Protocol (SMTP) is an Internet standard for electronic mail (email) transmission. SMTP communication between mail servers uses TCP port 25.
An SMTP transaction consists of three command/reply sequences:
1. MAIL command, to establish the return address, also called return-path
2.  RCPT command, to establish a recipient of the message.
3.  DATA to signal the beginning of the message text; the content of the message, as opposed to its envelope. 
Advantage 
1. Easy to connect 
2. Connects to any system 
Disadvantage
1. There is no security/verification with SMTP itself. 
2. Viruses are easily spread via email attachments 



]]> 2018-01-30 05:32:41 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/225942990 FTPS amanbayshady1 https://padlet.com/amanbayshady1/l77o104xegh2/wish/225943284 FTPS (FTP with Security) - a resulting combination would then carry the file transfer functionality inside an encrypted SSL/TLS tunnel that provides end-to-end encryption and transport security.
The security of FTPS connections can be set up in two distinct ways. The security methods are called “implicit” and “explicit”.

Pros
  • Commonly understood and utilized
  • Easy to implement
  • The interaction can be checked out and comprehended by a human
  • Offers services for server-to-server file transfer
  • Communications can be read by humans, making it easier to troubleshoot a connection attempt
  • Easily supported by mobile devices
Cons
  • Not all FTP servers support SSL/TLS 
  • Can’t perform file system operations
  • Uses multiple ports, making firewall configuration more complicated. 
]]> 2018-01-30 05:35:54 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/225943284 daniyarbekyerasyl https://padlet.com/amanbayshady1/l77o104xegh2/wish/225943645 2018-01-30 05:39:43 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/225943645 karbozov454 https://padlet.com/amanbayshady1/l77o104xegh2/wish/225943664 2018-01-30 05:39:56 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/225943664 amanbayshady1 https://padlet.com/amanbayshady1/l77o104xegh2/wish/225943717 2018-01-30 05:40:18 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/225943717 amanbayshady1 https://padlet.com/amanbayshady1/l77o104xegh2/wish/225943730 2018-01-30 05:40:27 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/225943730 TCP https://padlet.com/amanbayshady1/l77o104xegh2/wish/226211602 Communications between computers on a network is done through protocol suits. The most widely used and most widely available protocol suite is TCP/IP protocol suite. A protocol suit consists of a layered architecture where each layer depicts some functionality which can be carried out by a protocol. Each layer usually has more than one protocol options to carry out the responsibility that the layer adheres to. TCP/IP is normally considered to be a 4 layer system.
TCP
As indicated in the name, there are two layers to TCP/IP. The top layer, TCP, is responsible for taking large amounts of data, compiling it into packets and sending them on their way to be received by a fellow TCP layer, which turns the packets into useful information/data.

TCP/IP is needed to ensure that information reaches its intended destination. Without TCP/IP, packets of information would never arrive where they need to be and the Internet wouldn’t be the pool of useful information that we know it to be today.
 
A protocol system such as TCP/IP must be responsible for the following tasks:

  • Dividing messages into manageable chunks of data that will pass efficiently through the transmission medium.
  • Interfacing with the network adapter hardware.
  • Addressing: The sending computer must be capable of targeting data to a receiving computer. The receiving computer must be capable of recognizing a message that it is supposed to receive.
  • Routing data to the subnet of the destination computer, even if the source subnet and the destination subnet are dissimilar physical networks.
  • Performing error control, flow control, and acknowledgment: For reliable communication, the sending and receiving computers must be able to identify and correct faulty transmissions and control the flow of data.
  • Accepting data from an application and passing it to the network.
  • Receiving data from the network and passing it to an application. 
 Advantages:

    It can be used to establish/set up connection b/w different types of computers.
    It operates/works independently of the operating system.
    It support for a number of routing-protocols.
    It enables the internetworking between the organizations.
    It has a scalable, client-server architecture.

Disadvantages:

    It is complex to set up & manage.
    IPX is faster than TCP/IP model.
   

]]> 2018-01-30 17:23:55 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/226211602 https://padlet.com/amanbayshady1/l77o104xegh2/wish/226402371 2018-01-31 02:54:32 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/226402371 https://padlet.com/amanbayshady1/l77o104xegh2/wish/226412369 2018-01-31 04:08:20 UTC https://padlet.com/amanbayshady1/l77o104xegh2/wish/226412369