z
Enable
:
Tick
the
checkbox
to
enable
L2TP
VPN
server.
z
Remote
Start
IP
,
Remote
End
IP
:
L2TP
VPN
remote
network
IP
range,
between
start
IP
and
end
IP
there
must
be
less
than
10
available
IP
addresses.
z
Local
IP
:
L2TP
VPN
local
server
IP
address.
z
Primary
DNS
:
Primary
DNS
for
VPN
connection.
z
Alternate
DNS
:
Alternative
DNS
for
VPN
connection.
z
Authentication
Method
:
Select
the
authentication
method:
chap
or
pap.
pap
:
Password
Authenticate
Protocol,PAP
works
like
a
standard
login
procedure;
it
uses
static
user
name
and
password
to
authenticate
the
remote
system.
chap
:
Challenge
Handshake
Authentication
Protocol
CHAP
takes
a
more
sophisticated
and
secure
approach
to
authentication
by
creating
a
unique
challenge
phrase
(a
randomly
generated
string)
for
each
authentication.
z
Debug
:
Tick
to
enable
debug
for
L2TP
VPN
connection,
debug
info
will
be
written
into
system
logs.
z
IPSec
:
Enable
IPSecencryption
for
L2TP
VPN
server.
z
IPSec
Local
IP
:
CooVox
WAN
IP
which
can
access
Internet.
z
IPSec
Password
:
Define
a
password
for
IPSec
VPN
client
to
authenticate.
Notice
:
If
the
CooVox
IPPBX
system
is
behind
NAT,
you
need
to
open
ports
500,
4500
and
1701
on
the
router/firewall.
For
the
VPN
client
to
connect
you’ll
need
to
create
a
VPN
user
account.
Click
“
VPN
User
Management
”
tab
and
click
“
New
VPN
User
”
button
to
add
a
VPN
user
account.