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VoIP gateway IP400 version 5.01
thus can't be changed here.
• Leave the
Subscriber number
field empty, since it has no significance.
• Only outgoing PPPoE connections are possible, so uncheck the
Allow
incoming calls
box.
• Uncheck the
Assign remote IP address
box.
• Leave the
Check remote number
field blank, since it has no significance.
• Leave the
User
and
Password
fields empty in the
Incoming calls
area,
since they are of no significance.
• Leave the
Check remote number
field empty, since it has no significance.
• Enter the appropriate data in the
User
and
Password
fields in the
Outgo-
ing calls
area, if your gateway is to provide authentication at the called dis-
tant PPP terminal.
• Configure the IP routes as described in section “Configuration of the IP
routes” from page 32.
4.2.6 Settings for VPN connections with PPTP
The point-to-point tunnelling protocol (PPTP) implements virtual, private network
(VPN) connections via the Internet or other networks using the Internet protocol.
The PPTP connections are always dial-up connections. An IP address is dialled.
Authentication is performed by means of the user name and password. In addi-
tion, the transmitted voice data can be encrypted using Microsoft Point-to-Point
Encryption (MPPE). This is based on the requirement that the distant entity also
supports this process.
Since encoding and decoding always takes time, there may be some delay in voice
transmission, affecting the quality of the transmission. If quality loss is apparent,
you will have to decide for yourself between security or voice quality.
The innovaphone VoIP gateways can dial up to a remote server as PPTP client as
well as providing a dial-up access point themselves. PPTP is ideal to link up two
innovaphone VoIP gateways via the Internet.
Network address translation (NAT) is not required if both parties operate a net-
Tip
As a result, the called party is not assigned an IP address while the PPP con-
nection is being established. This is unusual for outgoing calls.