Telindus 1031, User And Reference Manual

Page: 131 / 394

Telindus 1031 Router Chapter 7
User manual Configuring the router
121
Incoming traffic (from the Internet)
Suppose the WAN IP network depicted in 7.4.3 - Configuring PAT on page 119 works in numbered
mode
1
. The incoming traffic from the Internet may be destined either for the local network, or for the Tel-
indus 1031 Router itself. The router treats incoming traffic on the PAT address as follows:
1. Numbered mode means that each WAN interface has an IP address. In that case, you need
the single official IP address for your WAN interface.
begin
Does the PAT address match
the IP address of the WAN
interface and is this port
number known by the router its
protocol stack (TMA, Telnet,
SNMP, TFTP)?
Destination IP address =
PAT address
AND
port number = previously
allocated port number for
outgoing traffic?
Transport protocol?
Router error
message?
Echo reply?
Echo request?
The route replies on
this request.
Search corresponding
request and send to
originator.
Send to originator that
caused the error.
The router forwards the
packet after IP address / port
number replacement on the
local network.
The router treats the packet
as a packet destined for him.
Discard the packet.
end
ICMP
TCP/UDP
no
no
no
no
no
yes
yes
yes
yes
yes