Filter
Top Products
Vigor2900 Series User’s Guide
73
z Data Filter - When there is an existing Internet connection, Data Filter is applied to
incoming and outgoing traffic. It will check packets according to the filter rules. If legal,
the packet will pass the router.
The following illustrations are flow charts explaining how router will treat incoming traffic
and outgoing traffic respectively.
S
S
t
t
a
a
t
t
e
e
f
f
u
u
l
l
P
P
a
a
c
c
k
k
e
e
t
t
I
I
n
n
s
s
p
p
e
e
c
c
t
t
i
i
o
o
n
n
(
(
S
S
P
P
I
I
)
)
Stateful inspection is a firewall architecture that works at the network layer. Unlike legacy
static packet filtering, which examines a packet based on the information in its header, stateful
inspection builds up a state machine to track each connection traversing all interfaces of the
firewall and makes sure they are valid. The stateful firewall of Vigor router not just examine
the header information also monitor the state of the connection.
I
I
n
n
s
s
t
t
a
a
n
n
t
t
M
M
e
e
s
s
s
s
e
e
n
n
g
g
e
e
r
r
(
(
I
I
M
M
)
)
a
a
n
n
d
d
P
P
e
e
e
e
r
r
-
-
t
t
o
o
-
-
P
P
e
e
e
e
r
r
(
(
P
P
2
2
P
P
)
)
A
A
p
p
p
p
l
l
i
i
c
c
a
a
t
t
i
i
o
o
n
n
B
B
l
l
o
o
c
c
k
k
i
i
n
n
g
g
As the popularity of all kinds of instant messenger application arises, communication cannot
become much easier. Nevertheless, while some industry may leverage this as a great tool to
connect with their customers, some industry may take reserve attitude in order to reduce
employee misusage during office hour or prevent unknown security leak. It is similar situation
for corporation towards peer-to-peer applications since file-sharing can be convenient but
insecure at the same time. To address these needs, we provide IM and P2P blocking
functionality.