I want to set up a system of 100-200 sensors that send their data (in a frequency of about 30 mins) to a MQTT broker based on RaspberryPi. Sensors data is obtained in an ESP8266, which would transmit via WiFi to the MQTT broker (which is in a distance of about 2 meters).
I wanted to know if is it possible for a broker of these characteristics to handle that many connections simultaneously.
Thank you so much!
Diego
A single broker can handle many 1000s of clients.
The limiting factor is likely to be the size and frequency of message, but assuming the messages are not 10s of megabytes each then 200 messages spread of 30mins will be trivial.
Even if they are all grouped at the same time rough time (allowing for clock drift) then small messages will again not be a problem.
Related
On my simulation, the are several nodes that are trying sending some message to a fixed RSU, I implemented a v2v communication, where the node send the message just to nodes that are closer to RSU. But sometimes, there are not nodes available to the sender node send the message, that is ok in simulations with a low density. But, when I increase the number of nodes, the delivery rate of messages decreases instead of increases, anyone already have this kind of problem?
I tried to adjust my algorithm to route less messages, because the problem might be on collisions.
I'm working on neighbor discovery protocols in wireless ad-hoc networks. There are many protocols that rely only on beacon messages between nodes when the discovery phase is going on. On the other hand, there are other approaches that try to transmit more information (like a node's neighbor table) during the discovery, in order to accelerate it. Depending on the time needed to listen to those messages the discovery latency and power consumption varies. Suppose that the same hardware is used to transmit them and that there aren't collisions.
I read that beacons can be sent extremely fast (less than 1ms easily) but I haven't found anything about how long it takes to send/receive a bigger message. Let say a message carrying around 50-500 numbers representing all the info about your neighbors. How much extra power is needed?
Update
Can this bigger message be divided into a bunch of beacon size messages? If it does, then I suppose the power used to transmit/listen grows linearly.
One possible solution is to divide the transmission in N different beacon-like messages with a small extra information to be able to put them back together. In this way, the power used grows linearly as N grows.
What is the max throughput of kafka in MB/second.
I am trying to send messages of size 2MB each and get a throughput of about 30 records per second (i.e. 60 MB/second)
I wanted to check what was the theoretical max throughput that could be reached.
Kafka is usually network bound -- so it depends on your hardware. Theoretical max for 1Gbit Ethernet would be 125MB/sec.
Also check out this blog post: https://engineering.linkedin.com/kafka/benchmarking-apache-kafka-2-million-writes-second-three-cheap-machines
I am sending data from my sensortag 2650 to the Node-RED platform through my smartphone. I am sending at the speed of 10 Hz. But the node is spitting out data at 1 Hz. How can I increase the data rate of the Node ibmiot?
ibmiot node does not play any role in setting the frequency of message rate. Thats done by the node which is sending the events to ibmiot node. So you need to change that part of the flow.
I want to know how can one calculate bandwidth requirements based upon flows and viceversa.
Meaning if I had to achieve total of 50,000 netflows what is the bandwidth requirement to produce this number? Is there a formula for this. I'm using this to size up flow analyzer appliance. If its license says supports 50,000 flows what does this means. How more bandwidth if i increase I would lose the license coverage?
Most applications and appliances list flow volume per second, so you are asking what the bandwidth requirement is to transport 50k netflow updates per second:
For NetFlow v5 each record is 48 bytes each with each packet carrying 20 or so records, with 24 bytes overhead per packet. This means you'd use about 20Mbps to carry the flow packets. If you used NetFlow v9 which uses a template based format it might be a bit more, or less, depending on what is included in the template.
However, if you are asking how much bandwidth you can monitor with 50k netflow updates per second, the answer becomes more complex. In our experience monitoring regular user networks (using google, facebook, etc) an average flow update encompasses roughly 25kbytes of transferred data. Meaning 50,000 flow updates per second would equate to monitoring 10Gbps of traffic. Keep in mind that these are very rough estimates.
This answer may vary, however, if you are monitoring a server-centric network in a datacenter, where each flow may be much larger or smaller, depending on content served. The bigger each individual traffic session is, the higher the bandwidth will be you can monitor with 50,000 flow updates per second.
Finally, if you enable sampling in your NetFlow exporters you will be able to monitor much more bandwidth. Sampling will only use 1 in every N packets, thus skipping many flows. This lowers the total number of flow updates per second needed to monitor high-volume networks.