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Cyclone for ARM devices User Manual
Cyclone for ARM
®
devices
Switches
The aforementioned type of process, where the data is simply
replicated onto every available port, quickly becomes inefficient for
larger sized networks. For this reason, a larger sized LAN employs
the usage of Switches instead of Hubs. A Switch is essentially a smart
Hub, in that it limits the input and output of data to the two transacting
computers.
Routers
Larger networks, such as Wide Area Networks (WANs), or the
Internet for that matter, use progressively more sophisticated devices
to transact data. At the core of these devices is the Router, which
functions as a switch between networks.
The Cyclone performs irrespective of the connection mechanism, with one
very important caveat: it needs to be set up with the appropriate network
parameters for the underlying network architecture.
8.2
Network Parameters
A typical network becomes operational not after the physical connections
have been established, but after network parameters in the form of IP
(Internet Protocol) numbers have been assigned to the individual computers.
An IP number is a unique string that consists of four numbers ranging
between 0 and 255, separated by dots, e.g., 192.168.1.2. Every computer
that is on a network needs to have a unique IP number. The computer uses
this IP number to identify itself on the network, and also to address the
recipient of its data.
Assignation of this IP number is sufficient information to transact data on a
simple network connected by a hub. On a more complex network, however,
routing information becomes important. The routing information consists of
two more IP numbers. The first of these is called the Subnet Mask, and is
used to determine whether or not the destination address resides on the
same subnet (i.e., doesn’t need to be forwarded to another network). The
other IP number is the Gateway Address, which is the address of the
computer that handles forwarding and receiving of packets to and from other
networks.
Before first use, the Cyclone needs to be programmed with a unique IP
number, the Subnet Mask IP number, and also the default Gateway’s IP
number. This can be done via the USB or the Serial port, and is described in
