NETGEAR ProSAFE GS724Tv4, Руководство пользователя

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2.4. Dividing a LAN
Note:
If a port is moved from one VLAN to another, the port PVID Configuration procedure needs to be
applied to both VLANs. The rule is: If the ports on a VLAN are changed, update the PVID configuration.
2.3.2 Results from testing
For testing, the control PC was removed from port 13 of the switch and installed in port 19, becoming
g19.
A ping was used to indicate two isolated LANs had been produced on the two VLANs. PC 2 (g7) could
only ping the devices of ports 1 and 2. PC 1 (g19) could ping port 23, and via port 23 the Internet.
Table 2.2: Ping exchange between devices on isolated VLANs, one VLAN with two networks
g7 g19
192.168.14.9 192.168.8.7
255.255.255.0 255.255.0.0 255.255.255.0 255.255.0.0
g2
255.255.255.0
⇐⇒ ⇐⇒
g7
255.255.255.0
x x
g2
255.255.0.0
⇐⇒ ⇐⇒
g7
255.255.0.0
x x
g1
255.255.255.0
g23
255.255.255.0
⇐⇒ ⇐⇒
g19
255.255.255.0
x x
g1
255.255.0.0
⇐⇒
g23
255.255.0.0
⇐⇒ ⇐⇒
g19
255.255.0.0
x x
The rows in Table 2.2 collect together the ports/devices which were configured on the switch into the
two VLANs. A
indicates the ping was blocked, a ⇐⇒ indicates a successful ping, and a x indicates a
successful ping of the test PC itself.
Symmetry can be seen in the behaviours of the pings. The top two left-hand groupings in Table 2.2 show
similar behaviour to the botton two right-hand groupings. In those two groupings, the PC sending the
ping,
g7 and g19 respectively, were in the VLAN represented by the group. In particular the behaviour
of the g19 and g1 is noted. In this case, g19 and g1 had different network addresses although contained
on the same VLAN.
The other symmetry is between the bottom two left-hand groupings and the top right-hand groupings.
These indicate VLAN containing ports/devices
g2 and g7 , and that containing g1 , g23 , and g19 were
isolated from one another.
2.4 Dividing a LAN
A LAN is a network with a single network address. For the network of Figure 2.3 this network address
is
192.168.8.0
. Al devices on a LAN have access to all other devices on that LAN for they are in the
same address space , meaning they have the same network address. Note: same network address not the
same IP address .
In its default, or initial configuration a GS724Tv4 switch implements a single LAN in the default VLAN,
ID 1. All ports of the switch are initially members of VLAN 1. It is good practise not to use VLAN 1 as
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