Paradyne 9788 - Manual (Page 120)

5. Configuring the FrameSaver DSL Router
5-16 December 2002 9700-A2-GB20-20
IP Filtering
For more information about IP filtering, see the Hotwire MVL, ReachDSL, RADSL,
IDSL, and SDSL Cards, Models 8310, 8312/8314, 8510/8373/8374, 8303/8304,
and 8343/8344, User’s Guide
.
With NAT – When NAT is enabled and the IP filters are active, filtering is done on
the Ethernet port – upstream first, then downstream.
Upstream: From the client to the server
Downstream: From the server to the client
Land Bug Prevention
The router drops all packets received on a network PVC interface or the Ethernet
interface when the Source IP address is the same as the Destination IP address.
Smurf Attack Prevention
The router ignores requests to send an ICMP echo reply to the broadcast address
and ICMP echo requests with a destination of the broadcast address.
DSL
Public
Network
DSL/
Rx Filter
IP
Ethernet/
Tx Filter
Ethernet
Private
Network
DSL/
Tx Filter
IP
Ethernet/
Rx Filter
Filtering with NAT
00-16905
NAT
NAT
DSL
Public
Network
DSL/
Rx Filter
IP
Ethernet/
Tx Filter
Ethernet
Private
Network
DSL/
Tx Filter
IP
Ethernet/
Rx Filter
Filtering without NAT
00-16904