EverFocus EDR410H - Manual (Page 86)

10.3 Gateway Address
Each host in a LAN has a gateway. A gateway address is compo
octets (numbers in the range of 0 to 255) separated by decimal p
ork. For example, a Linksys router has
using this type of router within your
LAN, then your gateway would be the IP address of the Linksys router. The
reason
ay to your
twork. This is similar to the zip code of your address.
10.4
or network
ommu i
to ut
most co
y socket
programming. Sometimes, though, port numbers are made visible to the casual
user.
a URL like
the following:
h
In rt number used by the
Web browser to connect to the Web server. Normally, a Web site uses port
numb
be). In IP networking, port numbers can theoretically range from 0 to 65535. Most
popu
f the
range (such as 80 fo
house
the sa
ot open dress or what it is
ddre
spects of network
nection point for
o
sed of four
oints. The
gateway address is used to uniquely identify a host or computer on the LAN
which assigns the IP addresses to your netw
an IP address of 192.168.1.1. If you were
this would be your gateway is because the Linksys is assigning the IP
addresses for your network therefore the Linksys would be the gatew
ne
Virtual Ports
A port number represents an endpoint or "channel" f
c n cations. Port numbers allow different applications on the same computer
ilize network resources without interfering with each other. Port numbers
mmonly appear in network programming, particularl
For example, some Web sites a person visits on the Internet use
ttp://www.everfocus.com:8100/
this example, the number 8100 refers to the po
er 80 and this number need not be included with the URL (although it can
lar network applications, though, use port numbers at the low end o
r HTTP). This could be similar to the front door of your
. Without the door to the house being open you could not enter it. This is
me case with ports on a network. If the ports for a specific IP address are
then you could not gain access to that IP ad n
a
ssing.
Note: The term port also refers to several other a
technology. A port can refer to a physical con
peripheral devices such as serial, parallel, and USB ports. The term
port also refers to certain Ethernet connection points, such as those
n a hub, switch, or router.
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