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Skype's Principal Architect explains why peer-to-peer was eliminated

308 points by cantrevealname 13y ago

pronoiac 13y ago
Reasons given: * Avoiding things like the supernode crash from December 2012.[1] * Supporting the growing mobile share, which can't contribute as supernodes. [1] http://blogs.voxeo.com/voxeotalks/2010/12/23/skype-outage-i-run-a-supernode-and-heres-what-i-think-happened/ http://blogs.voxeo.com/voxeotalks/2010/12/23/skype-outage-i-...
ilaksh 13y ago
Peer-to-peer technologies not only make Skype obsolete, but also make it much harder to spy on people. By the way, use WebRTC or some completely peer-based video conferencing (WebRTC still uses central servers to establish connections). Don't use Skype. Doesn't make any sense from a technology standpoint or from a privacy standpoint or anything. I am actually amazed by how little discussion there is on Hacker News and reddit about peer-to-peer technologies for things like video conferencing, publishing and realtime data collaboration. This whole NSA thing should be enough to push things like named data networking/content centric networking, WebRTC and meshnets (http://www.reddit.com/r/darknetplan http://www.reddit.com/r/darknetplan) into the mainstream. I believe that we are going to move away from a lot of traditional ways of doing things pretty soon. For one, obviously centralized servers have to go. Replace that with encrypted, privacy-focused data oriented networking. Replace centralized internet backbones with wifi meshnets, private laser systems, even private fiber networks, etc. Its very nice to have a simple programming language and API available with things like Webkit and Mozilla browsers, but that still puts too much power in the hands of a few companies, and locks us into particular implementations, and also traps us within the browser. Programmers and businesses do need easy-to-use, cross-platform and cross-device APIs and programming languages. I think we can port a lot of the Web APIs to a language-neutral, binary-neutral, implementation-neutral semantic representation. Dump as much of the unnecessary complexity from Web APIs as possible. Take a look at what HTML/SVG etc. provide and re-engineer a more general purpose solution for representing all kinds of things _including_ software source code that is based on truly semantic representation inspired by description logics which separates presentation from display/editing.
- randallu 13y ago
  > WebRTC still uses central servers to establish connections WebRTC without a signalling server: http://blog.printf.net/articles/2013/05/17/webrtc-without-a-signaling-server/ http://blog.printf.net/articles/2013/05/17/webrtc-without-a-...
  - brianchu 13y ago
    That is not even close to a solution. Then problem of establishing a connection (sharing connection info with both parties) remains in its entirety. The user still has to manually give the other user signaling information. The suggestion given is instant messaging chat (which requires a server). Not to mention that a STUN server is still needed for NAT traversal, as the author acknowledges.
    - jnbiche 13y ago
      What do you think about http://openpeer.org/ http://openpeer.org/ as a possible solution to the signaling problem?
- burntsushi 13y ago
  > This whole NSA thing should be enough to push things like named data networking/content centric networking You're damn right. It wasn't even a few days after this whole thing broke that I started working on a simple, distributed and automatic file synchronization program. No third parties and open source. I was absolutely stunned to find out that nothing out there meets those criteria (despite my best efforts). The only thing that was close was git-annex assistant, but I don't want to use git for simple file synchronization (particularly for large files). There's also Bittorrent Sync, but it's completely locked down. :-/
  - pwnna 13y ago
    This is all good but the biggest thing right now is that there is no coordinated effort to build a system that's easy to use, secure, and open source. Everyone can spend their time working on their own solution but no one would use it as everyone's work will be incompatible with each other. This means no one (or rather, not enough people) will use any solutions that are developed and revert back to something like Skype, FB message, etc. I think what we need is to establish a foundation that coordinates the development efforts for these secure and reliable software packages with a few centralized projects that become a standard (here's hope for WebRTC).
dfc 13y ago
Archive that displays more than a paltry 15 lines at once: https://www.listbox.com/member/archive/247/2013/06/sort/time_rev/page/1/entry/4:269/20130623090855:0B714E0A-DC06-11E2-9F35-8CD4CCA160A2/ https://www.listbox.com/member/archive/247/2013/06/sort/time...
- lancewiggs 13y ago
  And the original submission that points to it. fwiw: http://news.ycombinator.com/item?id=5929404 http://news.ycombinator.com/item?id=5929404
Aloha 13y ago
The reasons given lined up with my own thoughts. It's very hard to build a stable, reliable and self repairing distributed network. Communicating status and presence info is the largest challenge that distributed networks is the hardest and most difficult challenge you have, whereas with a centralized server, and 'register' its fairly easy to push updates out for all of this. Also, the server can be set to maintain status for the subscriber, even if they are not really connected.
runn1ng 13y ago
To anyone using Skype for actual work, the problems with peer-to-peer messaging become rather obvious, as messages from one device appear only when both that device and the receiver are online, which gets really chaotic when communicating with more people at the same time. Basically, the perception is "if you don't send the message when all of you are online, really weird things happen".
- pwnna 13y ago
  Still, that does not mean that encryption needs to be dropped (or e2e encryption needs to be dropped, or that MS has your encryption keys).
- jnbiche 13y ago
  Bitmessage is a peer-to-peer messaging system that doesn't require both participants to be online at the same time to exchange messages: White paper: https://bitmessage.org/bitmessage.pdf https://bitmessage.org/bitmessage.pdf [pdf link]
- mistermann 13y ago
  One related thing that bothers me, if you use more than one computer for your Skype chats, the conversations aren't fully synchronized among your PC's. With always on supernodes, this is trivial, yet it still doesn't work. How Skype itself never fixed this, and MS after spending billions on the acquisition also still hasn't fixed it boggles my mind. If they're not fixing simple but very important bugs like this, what are all those developers working on?
drivebyacct2 13y ago
I've been saying this for, probably close to a year now. Moving supernodes from being personal consumers to running in a cloud is a good thing and has minimal impact on privacy. Even comments here indicate people clearly didn't read this email or fail to understand it at all.
- deleted 13y ago
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- pwnna 13y ago
  Maybe I am understanding the system wrong.. but can you explain how it is good for privacy when Microsoft can decrypt your messages (They acknowledged that by saying they can do spam filtering and link blocking). I am unaware of a way to ensure privacy but still have a third party have the ability to read your messages. However, I'm open to ideas.
  - tjohns 13y ago
    You're both talking about two different topics... The location of the "supernodes" (on client machines, or in a datacenter) is separate from whether encrypted traffic can be read by a third party. Using a totally decentralized system makes it a little harder to eavesdrop, but it's entirely possible to develop a completely secure system in the centralized model. That said, I've never been terribly impressed with Skype's security model. Even before Microsoft bought them. It might have been decentralized, and the traffic might be encrypted, but the encryption lacks a strong trust model. There's never been any way to make sure that your connection hasn't been MITM'ed, since the system doesn't provide any way to verify the identity (key fingerprint) of the person you're talking to. The current encryption is fine if you're worried about rogue network administrators, but has never been sufficient if you're worried about being targeted by state actors.
    - pwnna 13y ago
      I understand the concept of having a secure centralized network. I'm interested in attempting to learn about such one myself (and perhaps one day contribute or implement one). It just seem like the original comment said that security is totally fine now, which I feel like is incorrect. For Skype's security model, I thought that before MS bought them they had E2E encryption (sure, it can be MITM'ed, but the conversation's that's not MITM'ed cannot be decoded easily, whereas they could be now). (Is it fair to say that I verify _some_, not all, of my friends' identity via the way the talk? I feel like if I have E2E encryption, I would be fine as a MITM would have a pretty difficult time faking how some of my friends talk.)
nadaviv 13y ago
Most of the points mentioned make it reasonable to use central servers, but why did they need to drop the p2p encryption? The only thing that seems related is "and other nice features like spam filtering and malicious URL removal" which he briefly mentions, but I don't find it a good enough reason to drop encryption and make it possible to intercept communication. Seems like an awful tradeoff.
- nextweek2 13y ago
  Taking off my tin foil hat for a moment, I would propose that encryption adds latency which they felt most users didn't care about. However most users demand land line quality voice.
wfunction 13y ago
Relevant: http://arstechnica.com/security/2013/05/think-your-skype-messages-get-end-to-end-encryption-think-again/ http://arstechnica.com/security/2013/05/think-your-skype-mes...
crazygringo 13y ago
I'm curious... I understand that the Microsoft servers are functioning as supernodes now. But when one computer calls another, and neither are behind NAT/firewall/etc., is the actual audio stream going directly between computers, or are they both sending the actual audio to/from the Microsoft servers? Obviously Microsoft could choose to redirect it through their servers whenever desired, but I assume that audio communication is still direct, whenever possible?
- stephengillie 13y ago
  I don't think the scenario you're presenting is realistic. Either an exposed PC on the internet has its own firewall, or it's already exploited.
  - tokenizerrr 13y ago
    Same lan network?
    - stephengillie 13y ago
      Are you skyping people down the hall instead of walking to visit them? I can see a feasible argument for this when you're talking about routing it through your WAN, but if you're that concerned about internal security then you should roll your own voicechat solution that you can keep on your own self-hosted (non-cloud) internal servers.
      - riquito 13y ago
        It's common practice to use a chat system inside a company, and instead of people shouting or constantly walking to their peers everyone write from their pc instead of visit the others (for most of the little requests).
        lucaspiller 13y ago
        A lot of companies still give each employee a telephone on their desk too.
anologwintermut 13y ago
Its funny, people got so caught up on the fact that Microsoft must have changed Skype's architecture to allow wiretapping. Via Snowden/PRISM we know wiretapping of Skype was possible well before the acquisition, let alone the redesign.
- acqq 13y ago
  Exactly! Prism slide: Skype: 2/6/11 http://en.wikipedia.org/wiki/File:Prism_slide_5.jpg http://en.wikipedia.org/wiki/File:Prism_slide_5.jpg But "Microsoft to acquire Skype": May 10, 2011 http://news.cnet.com/8301-13506_3-20061371-17.html http://news.cnet.com/8301-13506_3-20061371-17.html
mtgx 13y ago
What about collecting all https links, with the excuse that they're protecting you against spam (as if most spam links are https)?
- throwawaykf 13y ago
  In a previous discussion on HN, a HN user checked and confirmed that MS servers hit both HTTP and HTTPS links. Unfortunately I can't find that comment at the moment, so here's an Ars article that reports the same behavior: http://arstechnica.com/security/2013/05/think-your-skype-messages-get-end-to-end-encryption-think-again/ http://arstechnica.com/security/2013/05/think-your-skype-mes...
deleted 13y ago
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bifrost 13y ago
As a network engineer, I always knew when skype was misbehaving because those users always came up to me and complained. They complained because our corporate firewalls blocked them for using thousands and thousands of TCP connections when they became supernodes. They asked "how do we fix this" and sadly the answer was generally (if you were on a mac), you don't, just shutdown your client when you're not using it and it won't become a supernode. It wouldn't really have been a big deal if it was 5-10 connections, but it wasn't so it became a problem. I assume eliminating the crypto has to do with eliminating overhead, but it could have to do with DPI and making it more firewall friendly.
bosky101 13y ago
> > these devices are a lot different: they're running on battery, sometimes on WiFi > but often on expensive (both in money and battery) 2G or 3G data networks, > and essentially "off" most of the time. > On iOS devices, applications are killed and evicted from memory when they attempt > to do too much background processing or use too much memory. > On Windows RT and Windows 8 Modern applications, when the application is not in > the foreground we only get a few seconds of CPU execution time every 15 minutes > and again, strict memory limitations if we want to stay loaded. > And when the Skype application is unloaded, it can no longer receive incoming > calls or IMs, rendering it a lot less useful. > This is pretty much why/how all IM clients for iphone/ipad/android work as well. ( i work on verbs.im, we're a team of 4 now, here's a link to our privacy policy http://includetech.co/privacy/verbs http://includetech.co/privacy/verbs) The server becomes a proxy for your account, and being able to send push notifications. Your apps become thinner clients needing lesser battery, bandwidth. Infact we've got a step further, and replaced XMPP/HTTP with MQTT to save even more battery. ( here's a nice article profiling power consumption of MQTT vs HTTP here across wifi/3g: http://stephendnicholas.com/archives/1217 http://stephendnicholas.com/archives/1217 ) That being said, the recent iOS 7 have introduced API's for longer running background apps ~B
- Torgo 13y ago
  I don't know why this necessitates the removal of supernodes though, because it has always been the case that desktop clients could disable supernode functionality with a checkbox option. Why would it ever be enabled (or even an option) on a mobile client? Or is the issue simply that the majority of clients have become non-supernode-capable and it became an issue? I wish he would have went into more detail on this because at first glance the explanation is not sufficient to justify the change.
  - wmf 13y ago
    Kaufman's point is that phones don't even have enough resources to be a normal Skype peer, let alone a supernode. Thus work had to be shifted from peers to servers. I guess they could have shifted all that work to supernodes, but it was probably simpler to just put that functionality in reliable MS data centers. Also, I don't know that it's safe to send iOS/Android push messages from random PCs.
TempleOS 13y ago
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smutticus 13y ago
When my non-technical friends want to Skype with me I tell them to go with Jitsi. ZRTP all the way. https://jitsi.org/ https://jitsi.org/ People with a clue should no longer be using Skype.
- specto 13y ago
  I attempted to use jitsi with ddg's xmpp server, however the video and audio would never work between us. It was always one or the other. I hope the kinks are worked out as I would like to stop using Skype asap.
noptic 13y ago
TL;DR Skype P2P performs on mobile devices so we removed the featues people loved about Skype and kept the name.
antocv 13y ago
I liked this part "In the case of instant messaging, we have merged the Skype and Windows Messenger message delivery backend services, and this now gets you delivery of messages even when the recipient is offline, and other nice features like spam filtering and malicious URL removal." And wish to add to that, other nice features like "censorship and loss of privacy." I remember when I ditched MSN in favor of a what I thought was a secure communications solution, I waved goodbye to Microsoft. Here I am again, my messages routed yet again through their backend.
- atesti 13y ago
  And let's not forget how Microsoft scanned all private urls that were mentioned inside Skype chats recently: http://seclists.org/fulldisclosure/2013/May/78 http://seclists.org/fulldisclosure/2013/May/78
  - bskap 13y ago
    Um yes, that's covered in the "malicious URL removal" part. Hard to do malicious URL removal without, you know, looking at the URLs to see if they need to be removed.
    - alephnil 13y ago
      Except that they only checked HTTPS URLs, and most malicious URLs are on HTTP, which they apparently not checked.
      - bskap 13y ago
        Are you an expert in this domain or are you just parroting what the article said? I can think of at least one reason for a spam filter to contact the computer for an HTTPS request but not for an HTTP request- you want to find out what certificate they're using.
vr000m 13y ago
WebRTC is not a silver bullet, it mainly standardizes the profile for enabling interoperable media (via SRTP, SDP,...) and an API to control it from JS. The signaling is open, so it is mainly up to the developer to decide the topology they want to enable: p2p, mesh, centralized MCU, hub-and-spoke, overlays, etc. However, in many cases you'd have to use a TURN server to communicate from within very restrictive firewalls. This turn server could possibly run by anyone, including you. Just need to call the appropriate API with your own TURN server. I run restund (a open source turn server) on an amazon instance and route my packets via that (I also remove all other ICE candidates and just keep the TURN).
magoon 13y ago
Sounds legit.
FiloSottile 13y ago
In the case of instant messaging, we have merged the Skype and Windows Messenger message delivery backend services, and this now gets you delivery of messages even when the recipient is offline, and other nice features like spam filtering and malicious URL removal. This relates well to the HTTPS url visiting thing of a while back.
deleted 13y ago
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dschiptsov 13y ago
To collect and store the data, stupid.)
hawleyal 13y ago
Why not let me run my own server then, for me and my friends?
preneur 13y ago
The original design of the Internet was peer to peer. This is not some revilutionary idea. It's getting back to the original design. Small scale peer to peer networks can still be achieved, easily, even in the presence of "firewalls", "ISP's" and "NAT". You need a least one reachable IP address to be able to pierce NAT and "bootstrap" the network. Easy. You need to do some simple encapsulation. Again, easy. You need an OS with a TAP interface. Easy? iPhone denies programmers the TAP device. And any other company controlling a mobile OS could easily block your peer to peer networking capability by interfering with your access to the TAP device. Maybe it makes more sense to distribute your peer to peer solution as part of an open source OS that will run on many hardware architectures than to distribute a solution that purports to run on all the popular OS's. Maybe "apps" don't have to run on the OS that does the peer to peer connection. Maybe they can run "through" it instead: point your router/gateway settings at this open source OS, running on some small form factor pocket-sized computer like the Pi, and voila, you have a decent simulation of the "original" end-to-end Internet that you can use with people you know (the original Internet was among people who knew each other).

308 points by cantrevealname 13y ago

Reasons given: * Avoiding things like the supernode crash from December 2012.[1] * Supporting the growing mobile share, which can't contribute as supernodes. [1] http://blogs.voxeo.com/voxeotalks/2010/12/23/skype-outage-i-run-a-supernode-and-heres-what-i-think-happened/ http://blogs.voxeo.com/voxeotalks/2010/12/23/skype-outage-i-...

ilaksh 13y ago

Peer-to-peer technologies not only make Skype obsolete, but also make it much harder to spy on people. By the way, use WebRTC or some completely peer-based video conferencing (WebRTC still uses central servers to establish connections). Don't use Skype. Doesn't make any sense from a technology standpoint or from a privacy standpoint or anything. I am actually amazed by how little discussion there is on Hacker News and reddit about peer-to-peer technologies for things like video conferencing, publishing and realtime data collaboration. This whole NSA thing should be enough to push things like named data networking/content centric networking, WebRTC and meshnets (http://www.reddit.com/r/darknetplan http://www.reddit.com/r/darknetplan) into the mainstream. I believe that we are going to move away from a lot of traditional ways of doing things pretty soon. For one, obviously centralized servers have to go. Replace that with encrypted, privacy-focused data oriented networking. Replace centralized internet backbones with wifi meshnets, private laser systems, even private fiber networks, etc. Its very nice to have a simple programming language and API available with things like Webkit and Mozilla browsers, but that still puts too much power in the hands of a few companies, and locks us into particular implementations, and also traps us within the browser. Programmers and businesses do need easy-to-use, cross-platform and cross-device APIs and programming languages. I think we can port a lot of the Web APIs to a language-neutral, binary-neutral, implementation-neutral semantic representation. Dump as much of the unnecessary complexity from Web APIs as possible. Take a look at what HTML/SVG etc. provide and re-engineer a more general purpose solution for representing all kinds of things _including_ software source code that is based on truly semantic representation inspired by description logics which separates presentation from display/editing.

randallu 13y ago
> WebRTC still uses central servers to establish connections WebRTC without a signalling server: http://blog.printf.net/articles/2013/05/17/webrtc-without-a-signaling-server/ http://blog.printf.net/articles/2013/05/17/webrtc-without-a-...
- brianchu 13y ago
  That is not even close to a solution. Then problem of establishing a connection (sharing connection info with both parties) remains in its entirety. The user still has to manually give the other user signaling information. The suggestion given is instant messaging chat (which requires a server). Not to mention that a STUN server is still needed for NAT traversal, as the author acknowledges.
  - jnbiche 13y ago
    What do you think about http://openpeer.org/ http://openpeer.org/ as a possible solution to the signaling problem?
burntsushi 13y ago
> This whole NSA thing should be enough to push things like named data networking/content centric networking You're damn right. It wasn't even a few days after this whole thing broke that I started working on a simple, distributed and automatic file synchronization program. No third parties and open source. I was absolutely stunned to find out that nothing out there meets those criteria (despite my best efforts). The only thing that was close was git-annex assistant, but I don't want to use git for simple file synchronization (particularly for large files). There's also Bittorrent Sync, but it's completely locked down. :-/
- pwnna 13y ago
  This is all good but the biggest thing right now is that there is no coordinated effort to build a system that's easy to use, secure, and open source. Everyone can spend their time working on their own solution but no one would use it as everyone's work will be incompatible with each other. This means no one (or rather, not enough people) will use any solutions that are developed and revert back to something like Skype, FB message, etc. I think what we need is to establish a foundation that coordinates the development efforts for these secure and reliable software packages with a few centralized projects that become a standard (here's hope for WebRTC).

dfc 13y ago

Archive that displays more than a paltry 15 lines at once: https://www.listbox.com/member/archive/247/2013/06/sort/time_rev/page/1/entry/4:269/20130623090855:0B714E0A-DC06-11E2-9F35-8CD4CCA160A2/ https://www.listbox.com/member/archive/247/2013/06/sort/time...

lancewiggs 13y ago
And the original submission that points to it. fwiw: http://news.ycombinator.com/item?id=5929404 http://news.ycombinator.com/item?id=5929404

Aloha 13y ago

The reasons given lined up with my own thoughts. It's very hard to build a stable, reliable and self repairing distributed network. Communicating status and presence info is the largest challenge that distributed networks is the hardest and most difficult challenge you have, whereas with a centralized server, and 'register' its fairly easy to push updates out for all of this. Also, the server can be set to maintain status for the subscriber, even if they are not really connected.

runn1ng 13y ago

To anyone using Skype for actual work, the problems with peer-to-peer messaging become rather obvious, as messages from one device appear only when both that device and the receiver are online, which gets really chaotic when communicating with more people at the same time. Basically, the perception is "if you don't send the message when all of you are online, really weird things happen".

pwnna 13y ago
Still, that does not mean that encryption needs to be dropped (or e2e encryption needs to be dropped, or that MS has your encryption keys).
jnbiche 13y ago
Bitmessage is a peer-to-peer messaging system that doesn't require both participants to be online at the same time to exchange messages: White paper: https://bitmessage.org/bitmessage.pdf https://bitmessage.org/bitmessage.pdf [pdf link]
mistermann 13y ago
One related thing that bothers me, if you use more than one computer for your Skype chats, the conversations aren't fully synchronized among your PC's. With always on supernodes, this is trivial, yet it still doesn't work. How Skype itself never fixed this, and MS after spending billions on the acquisition also still hasn't fixed it boggles my mind. If they're not fixing simple but very important bugs like this, what are all those developers working on?

drivebyacct2 13y ago

I've been saying this for, probably close to a year now. Moving supernodes from being personal consumers to running in a cloud is a good thing and has minimal impact on privacy. Even comments here indicate people clearly didn't read this email or fail to understand it at all.

deleted 13y ago
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pwnna 13y ago
Maybe I am understanding the system wrong.. but can you explain how it is good for privacy when Microsoft can decrypt your messages (They acknowledged that by saying they can do spam filtering and link blocking). I am unaware of a way to ensure privacy but still have a third party have the ability to read your messages. However, I'm open to ideas.
- tjohns 13y ago
  You're both talking about two different topics... The location of the "supernodes" (on client machines, or in a datacenter) is separate from whether encrypted traffic can be read by a third party. Using a totally decentralized system makes it a little harder to eavesdrop, but it's entirely possible to develop a completely secure system in the centralized model. That said, I've never been terribly impressed with Skype's security model. Even before Microsoft bought them. It might have been decentralized, and the traffic might be encrypted, but the encryption lacks a strong trust model. There's never been any way to make sure that your connection hasn't been MITM'ed, since the system doesn't provide any way to verify the identity (key fingerprint) of the person you're talking to. The current encryption is fine if you're worried about rogue network administrators, but has never been sufficient if you're worried about being targeted by state actors.
  - pwnna 13y ago
    I understand the concept of having a secure centralized network. I'm interested in attempting to learn about such one myself (and perhaps one day contribute or implement one). It just seem like the original comment said that security is totally fine now, which I feel like is incorrect. For Skype's security model, I thought that before MS bought them they had E2E encryption (sure, it can be MITM'ed, but the conversation's that's not MITM'ed cannot be decoded easily, whereas they could be now). (Is it fair to say that I verify _some_, not all, of my friends' identity via the way the talk? I feel like if I have E2E encryption, I would be fine as a MITM would have a pretty difficult time faking how some of my friends talk.)

nadaviv 13y ago

Most of the points mentioned make it reasonable to use central servers, but why did they need to drop the p2p encryption? The only thing that seems related is "and other nice features like spam filtering and malicious URL removal" which he briefly mentions, but I don't find it a good enough reason to drop encryption and make it possible to intercept communication. Seems like an awful tradeoff.

nextweek2 13y ago
Taking off my tin foil hat for a moment, I would propose that encryption adds latency which they felt most users didn't care about. However most users demand land line quality voice.

wfunction 13y ago

Relevant: http://arstechnica.com/security/2013/05/think-your-skype-messages-get-end-to-end-encryption-think-again/ http://arstechnica.com/security/2013/05/think-your-skype-mes...

crazygringo 13y ago

I'm curious... I understand that the Microsoft servers are functioning as supernodes now. But when one computer calls another, and neither are behind NAT/firewall/etc., is the actual audio stream going directly between computers, or are they both sending the actual audio to/from the Microsoft servers? Obviously Microsoft could choose to redirect it through their servers whenever desired, but I assume that audio communication is still direct, whenever possible?

stephengillie 13y ago
I don't think the scenario you're presenting is realistic. Either an exposed PC on the internet has its own firewall, or it's already exploited.
- tokenizerrr 13y ago
  Same lan network?
  - stephengillie 13y ago
    Are you skyping people down the hall instead of walking to visit them? I can see a feasible argument for this when you're talking about routing it through your WAN, but if you're that concerned about internal security then you should roll your own voicechat solution that you can keep on your own self-hosted (non-cloud) internal servers.
    - riquito 13y ago
      It's common practice to use a chat system inside a company, and instead of people shouting or constantly walking to their peers everyone write from their pc instead of visit the others (for most of the little requests).
      - lucaspiller 13y ago
        A lot of companies still give each employee a telephone on their desk too.

anologwintermut 13y ago

Its funny, people got so caught up on the fact that Microsoft must have changed Skype's architecture to allow wiretapping. Via Snowden/PRISM we know wiretapping of Skype was possible well before the acquisition, let alone the redesign.

acqq 13y ago
Exactly! Prism slide: Skype: 2/6/11 http://en.wikipedia.org/wiki/File:Prism_slide_5.jpg http://en.wikipedia.org/wiki/File:Prism_slide_5.jpg But "Microsoft to acquire Skype": May 10, 2011 http://news.cnet.com/8301-13506_3-20061371-17.html http://news.cnet.com/8301-13506_3-20061371-17.html

mtgx 13y ago

What about collecting all https links, with the excuse that they're protecting you against spam (as if most spam links are https)?

throwawaykf 13y ago
In a previous discussion on HN, a HN user checked and confirmed that MS servers hit both HTTP and HTTPS links. Unfortunately I can't find that comment at the moment, so here's an Ars article that reports the same behavior: http://arstechnica.com/security/2013/05/think-your-skype-messages-get-end-to-end-encryption-think-again/ http://arstechnica.com/security/2013/05/think-your-skype-mes...

deleted 13y ago

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bifrost 13y ago

As a network engineer, I always knew when skype was misbehaving because those users always came up to me and complained. They complained because our corporate firewalls blocked them for using thousands and thousands of TCP connections when they became supernodes. They asked "how do we fix this" and sadly the answer was generally (if you were on a mac), you don't, just shutdown your client when you're not using it and it won't become a supernode. It wouldn't really have been a big deal if it was 5-10 connections, but it wasn't so it became a problem. I assume eliminating the crypto has to do with eliminating overhead, but it could have to do with DPI and making it more firewall friendly.

bosky101 13y ago

> > these devices are a lot different: they're running on battery, sometimes on WiFi > but often on expensive (both in money and battery) 2G or 3G data networks, > and essentially "off" most of the time. > On iOS devices, applications are killed and evicted from memory when they attempt > to do too much background processing or use too much memory. > On Windows RT and Windows 8 Modern applications, when the application is not in > the foreground we only get a few seconds of CPU execution time every 15 minutes > and again, strict memory limitations if we want to stay loaded. > And when the Skype application is unloaded, it can no longer receive incoming > calls or IMs, rendering it a lot less useful. > This is pretty much why/how all IM clients for iphone/ipad/android work as well. ( i work on verbs.im, we're a team of 4 now, here's a link to our privacy policy http://includetech.co/privacy/verbs http://includetech.co/privacy/verbs) The server becomes a proxy for your account, and being able to send push notifications. Your apps become thinner clients needing lesser battery, bandwidth. Infact we've got a step further, and replaced XMPP/HTTP with MQTT to save even more battery. ( here's a nice article profiling power consumption of MQTT vs HTTP here across wifi/3g: http://stephendnicholas.com/archives/1217 http://stephendnicholas.com/archives/1217 ) That being said, the recent iOS 7 have introduced API's for longer running background apps ~B

Torgo 13y ago
I don't know why this necessitates the removal of supernodes though, because it has always been the case that desktop clients could disable supernode functionality with a checkbox option. Why would it ever be enabled (or even an option) on a mobile client? Or is the issue simply that the majority of clients have become non-supernode-capable and it became an issue? I wish he would have went into more detail on this because at first glance the explanation is not sufficient to justify the change.
- wmf 13y ago
  Kaufman's point is that phones don't even have enough resources to be a normal Skype peer, let alone a supernode. Thus work had to be shifted from peers to servers. I guess they could have shifted all that work to supernodes, but it was probably simpler to just put that functionality in reliable MS data centers. Also, I don't know that it's safe to send iOS/Android push messages from random PCs.

TempleOS 13y ago

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smutticus 13y ago

When my non-technical friends want to Skype with me I tell them to go with Jitsi. ZRTP all the way. https://jitsi.org/ https://jitsi.org/ People with a clue should no longer be using Skype.

specto 13y ago
I attempted to use jitsi with ddg's xmpp server, however the video and audio would never work between us. It was always one or the other. I hope the kinks are worked out as I would like to stop using Skype asap.

noptic 13y ago

TL;DR Skype P2P performs on mobile devices so we removed the featues people loved about Skype and kept the name.

antocv 13y ago

I liked this part "In the case of instant messaging, we have merged the Skype and Windows Messenger message delivery backend services, and this now gets you delivery of messages even when the recipient is offline, and other nice features like spam filtering and malicious URL removal." And wish to add to that, other nice features like "censorship and loss of privacy." I remember when I ditched MSN in favor of a what I thought was a secure communications solution, I waved goodbye to Microsoft. Here I am again, my messages routed yet again through their backend.

atesti 13y ago
And let's not forget how Microsoft scanned all private urls that were mentioned inside Skype chats recently: http://seclists.org/fulldisclosure/2013/May/78 http://seclists.org/fulldisclosure/2013/May/78
- bskap 13y ago
  Um yes, that's covered in the "malicious URL removal" part. Hard to do malicious URL removal without, you know, looking at the URLs to see if they need to be removed.
  - alephnil 13y ago
    Except that they only checked HTTPS URLs, and most malicious URLs are on HTTP, which they apparently not checked.
    - bskap 13y ago
      Are you an expert in this domain or are you just parroting what the article said? I can think of at least one reason for a spam filter to contact the computer for an HTTPS request but not for an HTTP request- you want to find out what certificate they're using.

vr000m 13y ago

WebRTC is not a silver bullet, it mainly standardizes the profile for enabling interoperable media (via SRTP, SDP,...) and an API to control it from JS. The signaling is open, so it is mainly up to the developer to decide the topology they want to enable: p2p, mesh, centralized MCU, hub-and-spoke, overlays, etc. However, in many cases you'd have to use a TURN server to communicate from within very restrictive firewalls. This turn server could possibly run by anyone, including you. Just need to call the appropriate API with your own TURN server. I run restund (a open source turn server) on an amazon instance and route my packets via that (I also remove all other ICE candidates and just keep the TURN).

magoon 13y ago

Sounds legit.

FiloSottile 13y ago

In the case of instant messaging, we have merged the Skype and Windows Messenger message delivery backend services, and this now gets you delivery of messages even when the recipient is offline, and other nice features like spam filtering and malicious URL removal. This relates well to the HTTPS url visiting thing of a while back.

deleted 13y ago

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dschiptsov 13y ago

To collect and store the data, stupid.)

hawleyal 13y ago

Why not let me run my own server then, for me and my friends?

preneur 13y ago

The original design of the Internet was peer to peer. This is not some revilutionary idea. It's getting back to the original design. Small scale peer to peer networks can still be achieved, easily, even in the presence of "firewalls", "ISP's" and "NAT". You need a least one reachable IP address to be able to pierce NAT and "bootstrap" the network. Easy. You need to do some simple encapsulation. Again, easy. You need an OS with a TAP interface. Easy? iPhone denies programmers the TAP device. And any other company controlling a mobile OS could easily block your peer to peer networking capability by interfering with your access to the TAP device. Maybe it makes more sense to distribute your peer to peer solution as part of an open source OS that will run on many hardware architectures than to distribute a solution that purports to run on all the popular OS's. Maybe "apps" don't have to run on the OS that does the peer to peer connection. Maybe they can run "through" it instead: point your router/gateway settings at this open source OS, running on some small form factor pocket-sized computer like the Pi, and voila, you have a decent simulation of the "original" end-to-end Internet that you can use with people you know (the original Internet was among people who knew each other).