S R A / S F X 2 1 0 0 S E R I E S S A T E L L I T E R E C E I V E R
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Static Routing
The Static Routing submenu maintains the static routing table associated with the receiver.
Each receiver can support up to 32 static routes. The routing subsystem determines where
outgoing unicast IP packets are sent and applies to all IP packets, regardless of the network
interface they originated from.
Static unicast routing is done using the Linux
Route
facility. Additional information can be
obtained online with the manual at sites such as
http://www.linuxcentral.com
(Linux Man
Pages, Administrative and Privileged commands). Additionally, you can contact IDC
Customer Service for additional information (see Chapter 5).
Packets are routed according to the following rules:
1. IP packets can originate from any of the available network interfaces and are
processed by the receiver in accordance with the data flow in Figure 4-9.
2. Routes may be entered in any order and allow IP packets to be routed out a
gateway, according to the destination address and netmask.
3. Packets addressed to a device on a receiver subnet are sent out on the applicable
physical network to which the receiver is attached.
4. Packets addressed to the global (i.e. limited) broadcast address are sent out on all
the applicable physical networks to which the receiver is attached.
5. Packets addressed to the receiver’s subnet broadcast address are sent out on the
applicable physical network to which the receiver is attached.
6. Multicast packets are sent out on the physical network in accordance with the
Multicast Routing rules (see
Multicast Routing
section).
7. Packets addressed to other subnets are sent to the appropriate gateway as
defined in the routing table.
8. All packets that cannot be sent out using the rules described above (1-7) are
discarded by the receiver.
9. An entry that has its Network Address and Netmask both set to 0.0.0.0 will
represent a Default Gateway, and only one such entry will be allowed in the
receiver. This Default Gateway will be the same as the Default Gateway
displayed on the Identity page (see Figure 4-3).
10. The Destination Address, Netmask, and Gateway entries must be expressed in
dotted decimal notation.
11. The Gateway Address cannot be a loopback, broadcast, or multicast address and
must be on the same subnet as the receiver. However, it cannot be the receiver’s
IP address.
12. The Network Address cannot be a loopback, broadcast or multicast address, and
cannot be on the same subnet as the receiver.
