Netgear WNR612 — понимание работы маршрутизатора и NAT для интернет-соединений [66/99]
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Netgear WNR612 — понимание работы маршрутизатора и NAT для интернет-соединений [66/99]

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Netgear WNR612 Инструкция по эксплуатации онлайн [66/99] 7840
Advanced Settings
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N150 2-Port Wireless Router WNR612v3
process information. Before forwarding your message to the remote computer, your router
has to modify the source information and create and track the communication session so that
replies can be routed back to your computer.
Here is an example of normal outbound traffic and the resulting inbound responses:
1. You open a browser and your operating system assigns port number 5678 to this
browser session.
2. You type http://www.example.com into the URL field and your computer creates a web page
request message with the following address and port information. The request message is
sent to your router.
Source address. Your computer’s IP address.
Source port number. 5678, which is the browser session.
Destination address. The IP address of www.example.com, which your computer finds
by asking a DNS server.
Destination port number. 80, which is the standard port number for a web server
process.
3. Your router creates an entry in its internal session table describing this communication
session between your computer and the web server at www.example.com. Before sending
the web page request message to www.example.com, your router stores the original
information and then modifies the source information in the request message, performing
Network Address Translation (NAT):
• The source address is replaced with your router’s public IP address. This is necessary
because your computer uses a private IP address that is not globally unique and
cannot be used on the Internet.
• The source port number is changed to a number assigned by the router, such as
33333. This is necessary because two computers could independently use the same
session number.
Your router then sends this request message through the Internet to the web server at
www.example.com.
4. The web server at www.example.com composes a return message with the requested web
page data. The return message contains the following address and port information. The
web server then sends this reply message to your router.
Source address. The IP address of www.example.com.
Source port number. 80, which is the standard port number for a web server process.
Destination address. The public IP address of your router.
Destination port number. 33333.
5. Upon receiving the incoming message, your router checks its session table to determine
whether there is an active session for port number 33333. Finding an active session, the
router then modifies the message to restore the original address information replaced by
NAT. Your router sends this reply message to your computer, which displays the web
page from www.example.com. The message now contains the following address and port
information.

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Узнайте, как маршрутизаторы обрабатывают интернет-трафик и выполняют NAT для обеспечения связи между вашим компьютером и веб-серверами. Пошаговое объяснение процесса.