Netopia R910 User Reference Manual page 100

10-100 User's Reference Guide
For Input Filter 2 set the Protocol Type to allow GRE as shown below.
Enabled:
Forward:
Source IP Address:
Source IP Address Mask:
Dest. IP Address:
Dest. IP Address Mask:
Protocol Type:
In the Display/Change IP Filter Set screen select Display/Change Output Filter.
Display/Change Output Filter screen
+-#----Source IP Addr----Dest IP Addr------Proto-Src.Port-D.Port--On?-Fwd-+
+-------------------------------------------------------------------------+
| 1 0.0.0.0
| 2 0.0.0.0
For Output Filter 1 set the Protocol Type and Destination Port information as shown below.
Enabled:
Forward:
Source IP Address:
Source IP Address Mask:
Dest. IP Address:
Dest. IP Address Mask:
Protocol Type:
Source Port Compare...
Source Port ID:
Dest. Port Compare...
Dest. Port ID:
Established TCP Conns. Only:
Change Input Filter 2
Yes
Yes
0.0.0.0
0.0.0.0
0.0.0.0
0.0.0.0
GRE
0.0.0.0 TCP
0.0.0.0 GRE
Change Output Filter 1
Yes
Yes
0.0.0.0
0.0.0.0
0.0.0.0
0.0.0.0
TCP
No Compare
0
Equal
1723
No
NC =1723 Yes Yes |
-- -- Yes Yes |