360 Systems DigiCart/E - Manual (Page 23)

Administration
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Chapter 2
Administration
This chapter discusses basic system interconnection and device addressing, server software installation and
configuration, and network communication protocols.
Assigning Network Addresses
Every device on an Ethernet network must have an address so that others can identify it. A server using the
DHCP (Dynamic Host Control Protocol) service usually sets the IP address automatically. Some servers
don’t provide DHCP. In that case, some routing switches can provide the DHCP service, or the IP address
can be set manually.
Automatic Assignment
A benefit of automatic IP address assignment is that devices on the network can come and go, and the
network automatically adapts to the change. There is no need for system administrators to keep records of
address assignments.
The IP addresses of all devices on an Ethenet Audio network are normally in the range 192.168.1.0 to
192.168.255.255. This special allocation of IP addresses is dedicated to small local area networks and thus
would not be used over the global Internet. That is, the first two octets in the address are always “192.168”.
The third octet is the sub-network number.
The DHCP Server uses “Scopes” to define a range of IP Addresses it will issue (or “lease”) to clients. The
Scope determines the beginning and ending IP Addresses of a continuous range, and also can contain
Exclusions, which are addresses or ranges of addresses within the Scope that it will not issue.
You can configure your DHCP server to use any number between 1 and 255. We recommend using sub-net 1
for network interface card #1, subnet 2 for NIC 2, etc.
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If you are ever going to be using DigiCart/E recorders
with fixed addresses on the network, select the value “1” or “2”, because the first three octets of a fixed
DigiCart IP address are always “192.168.1” or “192.168.2”. The final octet would be automatically assigned
by the DHCP server. A different number is assigned to each device on the network.
The subnet mask is set to 255.255.255.0.
When a DHCP server assigns an IP Address, it also assigns a lease time for the address. In the event that a
particular client does not log in within the lease time, the lease expires and the IP Address is then reclaimed to
be leased to another client. This is set in the DHCP Scope. Scopes that serve DigiCart/E units should have
lease time set to Unlimited. This prevents changes in the IP Addressing once it is established, unless an
administrator explicitly deletes the lease from the Scope. (If necessary, additional Scopes can be set up with
other lease times to service other types of clients.)
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When using two NICs in a Load Balancing/Fault Tolerant configuration, they share the same subnet number and DHCP Scope.