Customer Questions (FAQ):

a. Can Erallo’s nodes do directional location?
Yes -- Erallo Smart Nodes can be configured to provide the location information of each Smart Node (along with the sensor data). The location data of each Smart Node is either pre-configured into the Smart Nodes before deploying the network, or after deployment, it is uploaded into the Smart Nodes using a web-enabled management interface.

b. What are the power requirements and range?
The power of an unlicensed frequency is defined by the FCC. The range of the wireless network is also governed by the transmission power. If a customer’s required range extends past the default range of the frequency, then an Erallo Repeater Node is used to extend the range. The Repeater Nodes are “cascaded” to extend the range to the desired distance.

c. Can Erallo nodes transmit through buildings and take advantage of signal reflection?
The range inside a building is typically a function of the building material, construction and layout. There are always “wireless dark zones” in the building; however, with Erallo’s Wireless Planning Services, the site/facility is analyzed and dark zones identified before hand. Then, recommendations for optimal location layout and the use of Repeater Nodes eliminate the dark zones before deployment.

d. Can Erallo’s Mesh Networks accommodate 10-50 nodes in an ad-hoc installation?
Yes, Erallo’s Mesh Networking System easily accommodates networks with 50 nodes. In fact, Erallo’s technology has the capacity to deploy over 450 nodes in a network. The limit on the maximum number of nodes is a function of the bandwidth size used by each node. For example, if a Smart Node collects and transmits its sensor data continuously at a high rate, then the effective capacity of the network will drop due to wireless message collisions. Acceptable maximum node limit are typically determined during Erallo’s Wireless Planning Services.

e. What are the sizes of the nodes?
minimum size of the electronics is approximately the size of a quarter. finished size will depend on the sensors included

f. Can Erallo’s nodes store 20 to 50 readings per minute of 3 parameters?
Erallo’s Smart Node has 512KB of memory and is capable of 10,000 normal data units. We could easily satisfy this requirement.

g. Does Erallo’s components use unlicensed bands?
Yes

h. Can Erallo nodes provide accurate time stamps?
Our time stamp accuracy is in the range of milliseconds.

i. Is there a trade- off between transmission distance and power?
Ranges can easily be extended by using Erallo’s Repeater Node.

j. Can Erallo nodes transmit 10 to 30 feet and is store/forward possible?
We have conducted indoor wireless range studies for other customers. In a wooden structure, Erallo’s 433 MHz Smart Node transmits data between 60 and 200 feet. The large variation in the range is a factor of the building construction, multiple floors and volume of each room. Yes, store/forward is provided.

k. What network topologies does Erallo support?
Mesh Networks, Ad-hoc Networks, Self-configuring and self-healing Networks, Distributed Networks

l. How are routes determined?
The optimal route minimizes the number of hops and links used while ensuring the lowest error rate and congestion.

m. How long does a battery last?
Sampling at once per 100 seconds, a small (220 mAh) lithium coin cell will last 1.4 years and a large (1000 mAh) lithium cell will last for 6.5 years.

n. How does Erallo achieve such low power consumption?
On the software side, Erallo's protocol uses no polling, so the Radio is only on when it has data to transmit, and when it periodically checks for the presence of routers. On the hardware side, techniques are used to minimize unnecessary device activity and power consumption.

o. What software controls are used?
Our products are software controlled. The sensor sampling rate and transmitter output power can easily be controlled by the user to maximize battery usage. An easy to use Web-based user interface is provided to control operations of wireless nodes. The two way communication between monitoring station and nodes enables users to collect sensor data and issue management commands.

p. What is 802.15.4?
An emerging IEEE standard for low-power wireless personal-area network. The standard will specify Direct-Sequence Spread-Spectrum (DSSS) radios operating in three bands: 868 and 915 MHz and 2.4 GHz.

q. How do Erallo’s product components relate to 802.15.4?
Erallo use 802.15.4 radios. The software interface is common to all the radio units. This innovative method enable star-mesh networking, and develop complete solutions.