R3721-F3210-F3171-HP High-End Firewalls VPN Configuration Guide-6PW101

239
Item Descri
p
tion
User Address
Specify the address pool for assigning IP addresses to users on the peer
end, or assign an IP address to a user directly.
If you have specified an ISP domain in PPP authentication configuration,
the address pools in the ISP domain will be listed in the User Address list.
You can perform the following configurations:
• Click Add to add an address pool, as shown in Figure 157. See Table
25 for further details.
• Select an address pool and click Modify to enter the address pool
modification page. See Table 25 f
or configuration details.
• Select an address pool and click Delete to delete the address pool.
Assign
Address
Forcibly
Specify whether to force the peer end to use the IP address assigned by the
local end. If you enable this function, the peer end is not allowed to use its
locally configured IP address.
Advanced
Configuration
Hello Interval
Specify the interval between sending hello packets.
To check the connectivity of a tunnel, the LAC and LNS regularly send Hello
packets to each other. Upon receipt of a Hello packet, the LAC/LNS
returns a response packet. If the LAC or LNS receives no Hello response
packet from the peer within a specific period of time, it retransmits the
Hello packet. If it receives no response packet from the peer after
transmitting the Hello packet for three times, it considers that the L2TP
tunnel is down and tries to re-establish a tunnel with the peer.
The Hello intervals on the LAC and LNS ends of the tunnel can be different.
AVP Hidden
Specify whether to transfer attribute value pair (AVP) data in hidden mode.
With L2TP, some parameters are transferred as AVP data. You can
configure an LAC to transfer AVP data in hidden mode, so that AVP data
is encrypted before transmission for higher security.
This configuration takes effect only on an LAC.
Flow Control
Specify whether to enable flow control for the L2TP tunnel.
The L2TP tunnel flow control function is for control of data packets in
transmission. The flow control function helps in buffering and adjusting the
received out-of-order data packets.
Mandatory
CHAP
Specify user authentication on the LNS end.