EverFocus 920, Инструкция по эксплуатации

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identify a host or computer on the LAN which assigns the IP addresses to your network. For
example, a Linksys router has an IP address of 192.168.1.1. If you were using this type of router
within your LAN, then your gateway would be the IP address of the Linksys router. The reason
this would be your gateway is because the Linksys is assigning the IP addresses for your
network therefore the Linksys would be the gateway to your network. This is similar to the zip
code of your address.
10.4 Virtual Ports
A port number represents an endpoint or "channel" for network communications. Port numbers
allow different applications on the same computer to utilize network resources without
interfering with each other. Port numbers most commonly appear in network programming,
particularly socket programming. Sometimes, though, port numbers are made visible to the
casual user. For example, some Web sites a person visits on the Internet use a URL like the
following:
http://www.everfocus.com:8100/
In this example, the number 8100 refers to the port number used by the Web browser to connect
to the Web server. Normally, a Web site uses port number 80 and this number need not be
included with the URL (although it can be). In IP networking, port numbers can theoretically
range from 0 to 65535. Most popular network applications, though, use port numbers at the low
end of the range (such as 80 for HTTP). This could be similar to the front door of your house.
Without the door to the house being open you could not enter it. This is the same case with ports
on a network. If the ports for a specific IP address are not open then you could not gain access to
that IP address or what it is addressing.
Note: The term port also refers to several other aspects of network technology. A port
can refer to a physical connection point for peripheral devices such as serial, parallel,
and USB ports. The term port also refers to certain Ethernet connection points, such
as those on a hub, switch, or router.
10.5 Pre-Installation
Before we begin with the installation we must ask ourselves a few questions in order to figure
out where to begin with networking our DVR’s.
Do you have Hi-speed Internet? ______________
There are many types of high speed Internet available. Three commonly used ones are
T1, Cable, and DSL (in order of speed).