Comtech EF Data CDM-760 - Manual (Page 330)

Appendix F Revision 2
CDM-760 Advanced High-Speed Trunking Modem MN-CDM760
F–16
The CDM-760 HTTP Interface Configuration | Routing | Routes page (Figure F-5) provides the
ability to configure and manage static routes – you can edit existing routes, or add new routes.
You may also delete some or all routes if needed.
Whether you are editing existing routes or adding new routes, it is important to follow the
guidelines and examples that follow.
It is important to enter a valid Destination IP Address and Mask. This Network Address
(sometimes referred to as a Subnet ID) and Mask must be associated with each other.
For example: If you have a two (2) host subnet with IP Addresses 192.168.1.25 – 192.168.1.26,
your mask must be /30 or (255.255.255.252) and your Network Address must be 192.168.1.24.
More common Network Addresses are:
• XXX.XXX.XXX.0/24
• XXX.XXX.0.0/16
There are subnet calculators available online that can assist with subnet divisions, IDs, and
Broadcast Addresses. An example of these available utilities can be found online at
http://www.subnet-calculator,com.
Once you have specified the Destination IP Address and Mask, you must use the Interf. drop-
down list to select if the route is intended for the WAN or the LAN:
• Select toWAN to direct the modem to receive packets via the P0 | MGMT LAN port, and, if
the packet satisfies the route, to transmit the packets out of the modem over the satellite.
• Select toLAN to direct the modem to forward the packet from the WAN (satellite) to the
LAN connection (i.e., the P0 | MGMT port); you must enter the IP Address of the next hop
router the packets should be forwarded to. No route entries are required for packets that
have a final destination on the same subnet as the P0 | MGMT subnet.
In some cases, when the modem is acting as the remote/edge router, all of the user IP
Addresses are on the same subnet as the modem’s P0 | MGMT port. In this case, you only need
to configure the router to send all packets seen by the modem over the satellite with a single
entry:
If you enter an invalid subnet and mask for the route, the entry will be denied. Also,
if you are entering a route toLAN you must enter a valid IP Address that is on the
modem’s P0 / MGMT subnet or your entry will be denied.
Figure F-6 illustrates a basic point-to-point link with one CDM-760 located at the HUB Site, and
another CDM-760 located at the REMOTE Site. The Hub Site features internal servers and an
Internet connection; the Remote Site has four users.