Friday, February 10, 2012
BT nonsense with VPN
Thursday, January 19, 2012
Status report on the Internet of Things
Almost two years ago I wrote about the Internet of Things and what, in my view, the IoT did not encompass. In that post I argued that because nobody could really tell what the IoT was, it could be a good idea to start by discussing what it wasn't. There were mixed opinions, of course. My intention was to try to focus the discussion on the IoT a bit and try to avoid falling into the buzzword black hole. But two years down the line, how has the IoT discussion evolved? Has the community gained any focus or has it all finally spiralled out of... well, that, focus.
As you probably sense, my answer is going to be the second one. The last couple of years have seen an increase in conferences, books and journals dedicated to the Internet of Things. This is great, until you realise that most of these are just using the IoT as a buzzword just because is “in fashion”. Consequently, the majority of the papers submitted to these conferences and journals are written by researchers that have not changed their research topic, but they have just added “Internet of Things” to the titles of their papers to be able to publish in more places. Of course, since the conferences and journals had been set up in the first place just to attract more submissions, there is no real filtering on the suitability of the topics and anything with the IoT name on it will be deemed as within the scope. When these papers get eventually published, they send the signal that any topic remotely based to networking and the Internet is valid, and this contamination just goes on an on.
Basically, in my point of view we have seen little or no improvement in the understanding of what is the IoT, what are its implications and how it will actually work. I haven't found any publication talking about how the architecture of the IoT should be, what are its challenges, how can it be achieved or how far we are from it. Yes, there have been some papers describing enabling technologies and applications, but that doesn't really help without a generic, structured vision (and eventual agreement) in how all should fit together. At the same time I have not found much criticism on what is happening... it would almost seem that nobody wants to kill the golden egg hen. Of course, eventually all the research labelled now as IoT will jump to a new buzzword if it is convenient, stick to the old buzzwords if necessary, or none at all if that gives it better chances to be published / funded.
The Future Internet (or the future of the Internet, just to keep avoiding buzzwords) is of course still relevant, and research will inevitably carry on because it is a hugely important ICT area. One could argue that irrespectively of the community going somewhere with the IoT or not, research will continue in a very similar, if not identical, way. As argued earlier, the fact that research in this area has only changed the title of its publications when the IoT discussion became trendy, tells us that the popularity of the IoT will come and go without any major impact in research investment. So, if this is the case, will we then get to the same place regardless of how the research is labelled? Well, yes, but the path is also important. Eventually, the concepts that the IoT encompasses (whichever they are) will happen anyway, but a focus on a structured vision of the IoT would allow us to enjoy results earlier and better. For that reason it is sad to see how the grand vision of the Internet of Things becomes adulterated and diluted over time. Is it perhaps too late for the IoT? I think it is, but I would like to be wrong.
Tuesday, August 9, 2011
Things I learnt with ESXi
- sudo vmrun -T server -h https://127.0.0.1:8333/sdk -u user -p password suspend "[standard] machineName/machineName.vmx"
- rsync -a --password-file=/etc/rsyncd.scrt /var/lib/vmware user@IP_of_NAS::volume_name
- sudo vmrun -T server -h https://127.0.0.1:8333/sdk -u user -p password start "[standard] machineName/machineName.vmx"
- To backup through NFS, you need to add an NFS data storage to your ESXi server using the vSphere client. Once you do that, make sure that you point your configuration files to there.
- Once you manually test that your configuration works, don't forget to set up a cron job as explained in the same web page.
- You will need to install vmware tools on your VMs so the script can stop your VM before starting the backup. If your host is Ubuntu, make sure you read this for doing that.
Monday, August 30, 2010
Installing Linux without CD, Floppy Disk or USB
Monday, March 22, 2010
What the Internet of Things is NOT
The “Internet of Things” is a very popular term that many mention but few seem to exactly know what is about. Is one of those buzzwords that are gaining momentum and that walk the line, still uncertain if they will reach the other side. As a good buzzword, the IoT is rather abstract, and aside conceptual definitions, it is very hard to tell exactly what the Internet of Things is. Is because of that that rather than talking about what the IoT is, I will talk about what the IoT is not. With some luck, that will narrow down the scope for a more focused discussion in the future.
As if Weiser wouldn't have been referenced enough since he predicted the second wave of computing (4925 times according to Google, and counting), some seem to use interchangeably the IoT and the ubiquitous computing concepts. Although the miniaturization of computing devices and the ubiquitous services derived from their data is probably a requirement for the IoT, pervasive computing is NOT the Internet of Things. Ubiquitous computing doesn't imply the use of objects, nor it requires an Internet infrastructure. The miniaturized devices that Weiser envisioned could represent anything, and provide data for anything. And of course, in 1991, there was little Internet to go around, and although it could have formed part of the ubiquitous computing vision, I don't think it could be argued that global network connectivity was ever a requirement for that vision.
The IoT is not the Internet Protocol
The Internet as we know it can be used globally because clients and servers use the same protocol for communication: the Internet Protocol (IP). It therefore appears logical that the Internet of Things must also run the IP (since is the same Internet, some might say), and that all the new clients to this extended Internet, the “things”, must connect to the same network and therefore run the Internet Protocol as well, right? Wrong. Of course, in a perfect world of limitless power on effortlessly miniaturized wireless devices integrated in everyday things, this would be true. But the reality is that the technologies that have the greatest potential, in terms of size and cost, to empower most of the IoT in the short term, can not run the Internet Protocol because they just don't have enough juice to do it. Examples of this are RFID or Wireless Sensor Networks. Some will argue that there are new low power versions of the IP aiming to running on very constrained devices. Acronyms such as 6LowPAN, ROLL or IPSO will surely be mentioned in those arguments. It is true that the IETF and other standardization bodies are making great efforts to reduce the footprint of IPv6 and related protocols, but they are still IP: a passive RFID tag can not run the IP, nor do many wireless sensor nodes based on the low-end hardware specs, which are precisely the cheapest ones and the most likely to become pervasive. What is more, there are already hundreds of millions of RFID tags and wireless sensor nodes out there, not to mention several billion mobile phones (largely without IP capabilities). Is the IoT going to be an elitist group of only IP-capable devices of which existing old or just cheap devices can not be part?
The IoT is not communication technologies
I was recently at a workshop where NEC Europe described LTE as an enabler for the Internet of Things. Be LTE as it may the next generation of cellular networks (with the permission of HSPA+), I have my reservations in that it has anything to do with enabling the IoT. If is about global connectivity, other older cellular technologies, although slower, also provide the same (or more) pervasive connectivity. In any case, the same reasons given for the IP apply, since Internet over cellular networks is implemented nowadays via IP stacks on the cellular modems. A similar reasoning can be applied to many other technologies that some insist in equalling to the Internet of Things. Technologies such as WiFi, Bluetooth, ZigBee / 802.15.4, 18000-7 come to mind. It is obvious that if things are going to be wirelessly connected to the Internet, they are going to need wireless communication technologies, the same way the “regular” Internet needs WAN and LAN connection technologies (e.g Ethernet) to interconnect millions of computers. However, we can not say that those technologies are the Internet, although they certainly might be part of it.
The IoT is not embedded devices
Words such as RFID or wireless sensor networks (WSN) have often been heard when discussing about he Internet of Things. Indeed, visionaries at the Auto-ID centre and other people working on RFID circa the year 2000 appear to be responsible for coining the term. They envisioned what is today the EPCnetwork, a set of distributed Internet resources that gather, filter, store and discover RFID data. Maybe because the term was never formally defined, because the vision has been extended with new technologies, or maybe just because other disciplines have seen on the Internet of Things an opportunity to attract an increasing interest, the IoT has come to mean much more that just networked RFID systems. Furthermore, too many times has RFID been used to describe what the IoT is without painting the back-end information infrastructures into the picture. If something the IoT is certainly not is a bunch of RFID tags attached to objects an read by random RFID readers. Another technology that has recently become popular when describing the IoT are sensor systems in general, and WSN in particular. This equivalence is even more inaccurate, because while RFID systems have at least certain standardized information architectures to which all the Internet community could refer, global WSN infrastructures have never been standardized and many, many times, not even considered. Some may say, however, that global Internet based sensor standards exist, to which I would reply: yes, but they were not built with “things” in mind (i.e they don't have a standardized way for uniquely identifying things!)
The IoT is not the applications
I recently read an article by The Hammersmith Group in which they talk about plants asking to be watered using wireless sensors, wine racks that know which bottles are stored and medicine bottles that issue warning if the medicines are not taken on time. They titled this article “The Internet of things: Networked objects and smart devices”. What we see here is another common misuse of the Internet of Things, very related with the pervasive computing issue described above. Think about somebody using Facebook or Google at the beginning of the 90's to describe what the Internet is. But is worse, because although I'm sure that we agree that Google is not the Internet, at least is well accepted that is an Internet-wide service. All these applications that many are describing as the IoT are just small services on an Internet-like scale. So, not only is absurd to use Internet application and services to describe the Internet itself, but it is even more illogical to refer to small applications that would have no real impact on a global Internet
Saturday, March 13, 2010
Wireless Communication for the Internet of Things
Thursday, March 4, 2010
Fun with port forwarding and SSH
client:~$ ssh-keygen
Leave all the values to default and use no password (simply press enter). Now, copy the key to gateway:
client:~$ ssh-copy-id -i .ssh/id_rsa.pub user_gateway@gateway_address
Now you can just ssh to gateway without using a password. Next, you might want to connect directly to target without having to SSH in gateway and from gateway to target. For this, you can set up a simple rule at your ssh_config file (normally in /etc/ssh/ssh_config) to forward text directly to targer through bridge:
ssh -L port_client:target:port_target user_gateway@gateway