Manual

Issue 3, August 2019 Model 374A User Guide
Page 18 Studio Technologies, Inc.
MODEL 374A
INTERCOM BELTPACK
Model 374A is identified using the Iden-
tify command within Dante Controller or
STcontroller all enabled talk channels will
be forced to their disabled state. If the
Global Kill Command method is enabled
the Model 374A will respond to any such
request and force all talk channels to their
disabled state.
Technical Notes
IP Address Assignment
By default the Model 374A’s Ethernet in-
terface will attempt to automatically obtain
an IP address and associated settings
using the DHCP (Dynamic Host Configu-
ration Protocol). If a DHCP server is not
detected an IP address will automatically
be assigned using the link-local protocol.
This protocol is known in the Microsoft®
world as Automatic Private IP Addressing
(APIPA). It is also sometimes referred to
as auto-IP. Link-local will randomly assign
a unique IP address in the IPv4 range of
169.254.0.1 to 169.254.255.254. In this
way multiple Dante-enabled devices can
be connected together and automatically
function, whether or not a DHCP server
is active on the LAN. Even two Dante-
enabled devices that are directly intercon-
nected using an RJ45 patch cable will,
in most cases, correctly acquire IP ad-
dresses and be able to communicate
with each other.
An exception does arise when trying to
directly interconnect two Dante-enabled
devices that use Ultimo integrated circuits
to implement Dante. The Model 374A
uses the Ultimo “chip” and, as such, a
direct one-to-one interconnection to an-
other Model 374A (or other Ultimo-based
product) is not supported. An Ethernet
switch linking the two units is required to
successfully interconnect two Ultimo-based
devices. The technical reason that a switch
is required relates to the need for a slight
latency (delay) in the data flow. And an
Ethernet switch will provide this. While this
is certainly an anomaly, since PoE power
is required for Model 374A operation it’s
highly unlikely that an application would
use two Model 374A units without a PoE-
enabled Ethernet switch being present.
Using the Dante Controller software ap-
plication the Model 374A’s IP address and
related network parameters can be manu-
ally set for a fixed (static) configuration.
While this is a more-involved process than
simply letting DHCP or link-local “do their
thing,” if fixed addressing is necessary then
this capability is available. But in this case
it’s highly recommended that each unit be
physically marked, e.g., directly using a
permanent marker or “console tape,” with
its specific static IP address. If knowledge
of a Model 374A’s IP address has been
misplaced there is no reset button or other
method to easily restore the unit to a de-
fault IP setting.
In the unfortunate event that a device’s IP
address is “lost,” the Address Resolution
Protocol (ARP) networking command can
be used to “probe” devices on a network
for this information. For example, in Win-
dows OS the arp –a command can be
used to display a list of LAN information
that includes MAC addresses and cor-
responding IP addresses. The simplest
means of identifying an unknown IP ad-
dress is to create a “mini” LAN with a
small PoE-enabled Ethernet switch con-
necting a personal computer to the Model
374A. Then by using the appropriate ARP
command the required “clues” can be
obtained.