M2M Cellular Gateway
Index skipping is used to reserve slots for new function insertion, when required.
3.b Routing
If you have more than one router and subnet, you will need to enable routing function to allow
packets to find proper routing path and allow different subnets to communicate with each other.
Routing is the process of selecting best paths in a network. It is performed for many kinds of networks,
like electronic data networks (such as the Internet), by using packet switching technology. The routing
process usually directs forwarding on the basis of routing tables which maintain a record of the routes
to various network destinations. Thus, constructing routing tables, which are held in the router's
memory, is very important for efficient routing. Most routing algorithms use only one network path at a
time.
The routing tables record your pre‐defined routing paths for some specific destination subnets. It is
static routing. However, if the contents of routing tables record the obtained routing paths from
neighbor routers by using some protocols, such as RIP, OSPF and BGP. It is dynamic routing. These both
routing approaches will be illustrated one after one.
3.b.1 Static Routing
"Static Routing" function lets you define the routing paths for some dedicated hosts/servers or
subnets to store in the routing table of the gateway. The gateway system will route incoming
packets to different peer gateways based on the routing table. You define the static routing
information in gateway system.
In "Static Routing" page, there are three configuration windows for static routing feature. They
are the "Configuration" window, "Static Routing Rule List" window and "Static Routing Rule
Configuration" window. The "Configuration" window lets you activate the global static routing
feature only. Even you have defined many static routing rules for the gateway, if you want to
disable them temporarily, just uncheck the Enable box to disable it. The "Static Routing Rule List"
window lists all your defined static routing rule entries. Using "Add" or "Edit" button to add and
create one new static routing rule or to modify an existed one. When "Add" or "Edit" button is
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