Does riacks offer any feature of virus scanning, or can an easy software be implemented on top ?
I did not find anything on the documentation.
Sorry Riak KV, TS, and S2 (formerly C2) do not offer any anti virus scanning functionality. You will need to implement your own anti virus capability in front of whichever Riak you use.
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I am pretty new to corda and I am curious if it is possible to do a cross compatibility zone DvP. According to https://www.corda.net/2017/08/compatibility-and-upgrades/ it is possible to have different corda newtorks in a global network.
My question addresses following use case:
let's say I have two corda networks (compatibility zones). Each network has its own notary, nodes, customers & KYC process and is supporting a certain asset.
The first network provides for example a payment infrastructure and the second network a securities network.
Is it possible to do that by using R3 corda, if yes is there any example/tutorial?
Thanks in advance for any support!
The answer is yes but I think we're talking at cross-purposes :) Networks operated and governed by different entities are intended to form and operate WITHIN a compatibility zone.
The way I think it's most helpful to think of Compatibility Zones is to imagine the concept just doesn't exist... imagine there was just ONE Corda network (ie CZ) that everybody used (that was transparently/openly governed so no one firm/group of firms controlled it)... and then all the different apps and business networks existed within it... able to interoperate and transact across each other, because their nodes were compatible... they would understand and accept each other's transactions, etc.
Think about it from the perspective of a firm installing a blockchain node: getting onto any blockchain network (a Corda CZ or whatever the equivalent concept is for other platforms)... getting an identity, punching the right holes in the firewall, setting up the node infrastructure... it's analogous to the work needed to get a firm "on the internet" - setting up routers, getting IP addresses, etc, etc.
It's the kind of thing you want to do once and then reuse ruthlessly. The idea that you would have to connect to an entirely new communications network for each app your firm used would be ludicrous. And yet that's how some people seem to think blockchain deployments should be: ie for each app, you set up a separate blockchain network with its own nodes and settings and identity layer and consensus providers. But that's surely just nonsense, right?
You want to connect to a global network once and then reuse that infrastructure.
So the idea is that we try to have as few CZs as possible and encourage as many business networks as possible to form within that small number of CZs.
I know this can mess with your mind when you first hear about it because all the other enterprise blockchain platforms are going in totally the wrong direction (in my opinion..!) They seem to be encouraging the formation of a separate private network for each application. But that just seems crazy to me.
So maybe try this: even if you think I'm mad, play along with the idea for a day or so and see if it begins to grow on you :) If not, let's debate it again but I really do think this idea of multiple apps on the same overall shared network (ie multiple business networks in a single compatibility zone) is just so amazingly powerful as a concept.
So to your answer: can you do cross-app/cross-business-network DvP within a CZ? Yes! That is one of the key use-cases we invented Corda to solve... it's almost perfect for those sorts of scenarios.
Could you do it if the two apps were on different CZs? Well, yes... but it would be like asking if you could do DvP between assets managed in different databases or hosted on different blockchains.. it's just messier... needing locking and 2PC and all the stuff that we can just eliminate if we hold ourselves accountable for not creating needless balkanisation/siloed deployment through deployment of standalone networks unless they're really, really needed.
I want to learn how to write a software using a peer to peer networking architecture but i don't know where to start, knowing that I use as a programming languages : c/c++ , lisp, a little of python. any pointer to documentation or tutorials is appreciated.
Why not just start with a Bittorrent API, such as https://github.com/JosephSalisbury/python-bittorrent, rather than writing your own.
After you have gained experience with a well-used P2P network, then you may start to see what you could do better, then start to write your own.
here are some guidelines which i found with google
So I want to learn all about networks. Well below the socket, down to raw sockets and stuff. And I want to understand hubs, routers, access points, etc. For example, I'd like to be able to write my own software to do this kind of stuff.* Is there a great source for this kind of information?
I know that I'm asking a LOT here, and that to fully explain it all requires from high level down to low level. I guess I'm looking for a source similar in scope and depth to Applied Cryptography, but about networks.
Thanks to anyone who can help to point me (and others like me?) in the right direction.
* Yes, I realize using any of my hand-crafted network stack code would be a huge security issue, and am only looking to do it to learn :)
Similar Question: here. However I'm looking for more than just 'what's below TCP/UDP sockets?'.
Edited for Clarification: The depth I'm talking about is above the driver level. So assuming that the bits can make it to and from the other end of the wire, what next?
I learned IP networking from TCP/IP Illustrated. Highly recommended.
This may not help you learn it, but a packet sniffer like Wireshark will give you some insight into what the data looks like at a pretty low-level protocol (TCP/IP).
As you have obviously recognised, the universe does not start and end with the IP Protocol. Take a look at the OSI 7 Layer Model where IP is a Layer 3 (Network) protocol. Common IP Routers will operate at this level, but there is more complexity you probably should understand in the Data Link and Physical layers before you start coding your own network stacks.
Start with the fundamentals of data communications in all its myriad forms and work your way up the stack until you get to where you need to stop. Data Communications, Computer Networking and Open Systems is a good foundation text, and then look for more detail on each area you need to focus on. Previous answers include good links for IP and TCP/IP, and as mentioned Wireshark will let you look down through some of the layers
CISCO CCNA materials contain a great network fundamentals, but does not affect programming aspect. I'm not sure that there is an official free link, but you can try to find them.
You should equip yourself with a c compiler and the necessary libs and headers for your OS and play around. You may want to read for example:
http://snap.nlc.dcccd.edu/learn/fuller3/chap13/chap13.html
I had some more links in my delicious account, but they all went down the digital drain ;-)
Have you any embedded programming experience ? If so I recommend you buy one of these development boards. They are cheap and allow you work on every part of the networking stack plus all the software tools required are free.
Note that getting going on it isn't easy and I ended up reading the CS8900 IC datasheet to learn how to make it communicate with the ARM7 based processor. But if you enjoy that sort of thing (as I do) then they are great fun.
Hmmm ... have you looked into Computer Networks by Tanenbaum ?
The TCP/IP Guide
I have found the networking chapter in "understanding the linux kernel" and "understanding linux network internals" from oreilly to be very helpful.
The TCP/IP stack is a very good start but there is a lot more and a good understanding of how ethernet works and how ethernet != IP != the-interweb will go a long way.
books on network security often do a decent if not goos job explaining how networks work in a concise context.
what really did the trick for me was taking a job implementing NAT :)
This course worked for me: COS 461 at Princeton. Note that it assumes system-level programming experience with C.
Pretty much all the readings and lectures are available online under "Syllabus". And you can try the assignments too (unfortunately, you won't have access to the Virtual Network System).
Check this.. it is a good collection of information:
http://www.tcpipguide.com/free/t_toc.htm
I'm looking for an OpenSource server monitoring tool that allows the following:
Monitor a variety of services on TCP, UDP.
Supports custom port numbers.
Supports some basic response checking (beyond initial connection checking).
Basic dashboard overview of health status.
Alert notifications via e-mail.
I could roll my own, but want to make sure I don't reinvent the wheel if there's a complete suite out there that does what I want (and maybe more!).
EDIT: Preferably software that runs on Windows.
I recommend the "mon" package (http://www.kernel.org/software/mon). It is pre-packages in most Linux distributions, and fairly customizable.
Nagios is the way to go. Very powerful and customizable. Has dashboards, history, alerts, graphs, and much more.
I you want something a bit fancier, there is Groundwork which is built on nagios and various other bits and pieces, but I didn't really like that after playing with it for a little bit. It also costs for anything but the community edition.
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I suppose this question is a variation on a theme, but different.
Torrents will never replace HTTP, or even FTP download options. This said, why aren't there torrent links next to those options on more websites?
I'm imagining a web-system whereby downloaded files are able to be downloaded via HTTP, say from http://example.com/downloads/files/myFile.tar.bz2, torrents can be cheaply autogenerated and stored in /downloads/torrents/myFile.tar.bz2.torrent, and the tracker might be /downloads/tracker/.
Trackers are a well defined problem, and not incredibly difficult to implement, and there are many drop in place alternatives out there already. I imagine it wouldn't be difficult to customise one to do what is needed here.
The autogenerated torrent file can include the normal HTTP server as a permanent seed, the extensions to do this are very well supported by most, if not all, of the major torrent clients and requires no reconfiguration or special things on the server end (it uses stock standard HTTP Range headers).
Personally, if I setup such a system, I would then speed limit the /downloads/files/ directory to something reasonable, say maybe 40-50kb/s, depending on what exactly you were trying to serve.
Does such a file delivery system exist? Would you use it if it did: for your personal, company, or other website?
first of all: http://torrent.ubuntu.com/ for torrents on ubuntu.
second of all: opera has a built in torrent client.
third: I agree with the stigma attached to p2p. So much so that we have sites that need to be called legaltorrents and such like because by default a torrent would be an illegal thing, and let us not kid ourselves, it is.
getting torrents into the main stream is an excellent idea. you can't tamper with the files you are seeding so there is no risk there.
the big reason is not really stigma. the big reason is analytics, and their protection. with torrents these people (companies like microsoft and such like) would not be able to gather important information about who is doing the downloads (not personally identifiable information, and quickly aggregated away). with torrents, other people would be able to see this information, at least partially. A company would love to seed the torrent of an evaluation version of a competing companys product, just to get an idea of how popular it is and where it is getting downloaded from. It is not as good as hosting the download on your webservers, but it is the next best thing.
this is possibly the reason why the vista download on microsofts sites, or its many service packs and SDKs are not in torrents.
Another thing is that people just wont participate, and that is not difficult to figure out why because of the number of hoops you have to jump through. you got to figure out the firewall, the NAT thing, and then uPNP thing, and then maybe your ISP is throttling your bandwidth, and so on.
Again, I would (and I do) seed my 1.5 times or beyond for the torrents that I download, but that is because these are linux, openoffice that sort of thing. I would probably feel funny seeding adobe acrobat, or some evaluation version or something, because those guys are making profits and I am not a fool to save money for them. Let them pay for http downloads.
edit: (based on the comment by monoxide)
For the freeware out there and for SF.net downloads, their problem is that they cannot rely on seeders and will need their fallback on mirrors anyway, so for them torrents is adding to their expense. One more reason that pops to mind is that even in software shops, Internet access is now thoroughly controlled, and ports on which torrents rely plus the upload requirement is absolutely no-no. Since most people who need these sites and their downloads are in these kinds of offices, they will continue to use http.
BUT even that is not the answer. These people have in their licensing terms restrictions on redistribution. And so their problem is this: if you are seeding their software you are redistributing it. That is a violation of their licensing terms so if they host a torrent download and allow you to seed it, that is entrapment and they can be sued (I am not a lawyer, I learn from watching TV). They have to then delicately change their licensing to allow distribution by seeding torrents but not otherwise. This is an easy enough concept for most of us, but the vagaries of the English language and the dumb hard look on the face of the judge make it a very tricky thing to do. The judge may personally understand torrents, but sitting up their in the court he has to frown and pretend not to because it is not documented in legalese.
That there is the ditch they have dug and there they fall into it. Let us laugh at them and their misery. Yesterdays smart is todays stupid.
Cheers!
I'm wondering if part of it is the stigma associated with torrents. The only software that I see providing torrent links are Linux distros, and not all of them (for example, the Ubuntu website does not provide torrents to download Ubuntu). However, if I said I was going to torrent something, most people associate it with illegal downloads (music, video, TV shows, etc).
I think this might come from the top. An engineer might propose using a torrent system to provide downloads, yet management shudders when they hear the word "torrent".
That said, I would indeed use such a system. Although I doubt I would be able to seed at home (I found that the bandwidth kills the connection for everyone else in the house). However, at school, I probably would not only use such a system, but seed for it as well.
Another problem, as mentioned in the other question, is that torrent software is not built into browsers. Until it is, you won't see widespread use of it.
Kontiki (which is very similar to bittorrent), makes up about 10% of all internet traffic by volume in the UK, and is exclusively used for legal distribution of "big media" content.
There are people who won't install a torrent client because they don't want the RIAA sending them extortion letters and running up legal fees in court when they (the RIAA) break into your computer and see MP3 files that are completely legal backup copies of CDs that were legally purchased.
There's a lot of fear about torrents out there and I'm not comfortable with any of the clients that would allow even limited access to my PC because that's the "camel's nose in the tent".
The other posters are correct. There is a huge stigmata against Torrent files in general due to their use by hackers and people who violate copyright law. Look at PirateBay, that is all they "serve" are torrent files. A lot of cable companies in the US have started traffic shaping Torrent traffic on their networks as well because it is such a bandwidth hog.
Remember that torrents are not a download accellerator. They are meant to offload someone who cannot afford (or maybe just doesn't desire) to pay for all the bandwidth themselves. The users who are seeding take the majority of the load. No one seeding? You get no files.
The torrent protocol is also horrible for being so darn chatty. As much as 40% of your communications on the wire can be control flow messages and chat between clients asking for pieces. This is why cable companies hate it so much. There are some other problems of the torrent end game (where it asks a lot of people for final parts in an attempt to complete the torrent but can sometimes end up with 0 available parts so you are stuck with 99% and seeding for everyone).
http is also pretty well established and can be traffic shaped for load balancers, etc. So most legit companies that serve up their content can afford to host it, or use someone like Akamai to repeat the data and then load balance.
Perhaps its the ubiquity of http-enabled browsers, you don't see so much FTP download links anymore, so that could be the biggest factor (ease of use for the end-user).
Still, I think torrent downloads are a valid alternative, even if they won't be the primary download.
I even suggested Sourceforge auto-generate torrents for downloads, and they agreed it was a good idea.. but havn't implemented it (yet). Here's hoping they will.
Something like this actually exists at speeddemosarchive.com.
The server hosts a Metroid Prime speedrun and provides a permanent seed for it.
I think that it's a very clever idea.
Contrary to your idea, you don't need an HTTP URL.
I think one of the reasons is that (currently) torrent links are not fully supported inside web browser... you have to fire up the torrent client and so on.
Maybe is time for a little firefox extension/plugin? Damn, now I am at work! :)