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I love this! The only thing it would require in addition is if it was serverless and p2p, like torrent.

by Kenji 10y ago

HappyTypist 10y ago
You still need a mechanism for peer discovery.
- vbezhenar 10y ago
  Reserve few ports and connect to random IP address until you've found a node. Works only for IPv4, though.
  - problems 10y ago
    Yikes, no... we have much better ways than that. Typically bootstrapping a list of a few thousand nodes with top uptime is a good starting point, then using peer exchange between the nodes to find more, store them and prefer them when possible. Bittorrent DHT could also be (ab)used as a discovery mechanism.
    - vbezhenar 10y ago
      It's too easy to block those few thousand nodes and render the entire software useless. If I would start Tor on my PC, it won't connect to any nodes, because all bootstrap hosts are blocked by my provider. It's centralization with all related drawbacks.
      - problems 10y ago
        Not really - those few thousand nodes are only used for the initial bootstrap, once you've connected to the network or can get a node list from a friend once, you'll have more than that. And it's very hard to act legally against thousands of nodes instead of a single entity. Or to convince ISPs to block them all. Definitely an improvement over a centralized system. Some services will try to improve this further by only sending random nodes to each person who downloads, using the hash of their IP as an rng seed. Yes, an ISP who's willing to block a few thousand nodes will be able to take your shit down no matter what. That's why Tor uses private "bridge" servers for people in highly censored countries and tries to mask traffic as some other type. There's no way around that. But that doesn't mean decentralization is useless - it's incredibly useful in most countries and with most ISPs. If you need to scan IPv4 space randomly to find a node, you can easily find all nodes. This takes about a day or two on a cheap VPS.
ycmbntrthrwaway 10y ago
It is impossible to build anonymity system without some sort of centralization due to possibility of Sybil attack. You need some trusted entity beforehand, otherwise your ISP can just simulate the whole network for you and never let you connect to the real network without you even noticing this.
- sangel 10y ago
  I'm not sure that I agree with your point. DC networks (see David Chaum's work and also Dissent by Corrigan-Gibbs and Ford) have no centralized components and provide stronger anonymity than Vuvuzela. However, they are not very efficient for large user bases. This is different from being "impossible" though. The attack that you are describing seems to be a denial of service rather than a privacy violation. Centralized systems have similar issues though (your ISP could simply block packets to such system, one of the malicious centralized servers could refuse to process messages, etc.).

I love this! The only thing it would require in addition is if it was serverless and p2p, like torrent.

by Kenji 10y ago

I love this! The only thing it would require in addition is if it was serverless and p2p, like torrent.

HappyTypist 10y ago

You still need a mechanism for peer discovery.

vbezhenar 10y ago
Reserve few ports and connect to random IP address until you've found a node. Works only for IPv4, though.
- problems 10y ago
  Yikes, no... we have much better ways than that. Typically bootstrapping a list of a few thousand nodes with top uptime is a good starting point, then using peer exchange between the nodes to find more, store them and prefer them when possible. Bittorrent DHT could also be (ab)used as a discovery mechanism.
  - vbezhenar 10y ago
    It's too easy to block those few thousand nodes and render the entire software useless. If I would start Tor on my PC, it won't connect to any nodes, because all bootstrap hosts are blocked by my provider. It's centralization with all related drawbacks.
    - problems 10y ago
      Not really - those few thousand nodes are only used for the initial bootstrap, once you've connected to the network or can get a node list from a friend once, you'll have more than that. And it's very hard to act legally against thousands of nodes instead of a single entity. Or to convince ISPs to block them all. Definitely an improvement over a centralized system. Some services will try to improve this further by only sending random nodes to each person who downloads, using the hash of their IP as an rng seed. Yes, an ISP who's willing to block a few thousand nodes will be able to take your shit down no matter what. That's why Tor uses private "bridge" servers for people in highly censored countries and tries to mask traffic as some other type. There's no way around that. But that doesn't mean decentralization is useless - it's incredibly useful in most countries and with most ISPs. If you need to scan IPv4 space randomly to find a node, you can easily find all nodes. This takes about a day or two on a cheap VPS.

ycmbntrthrwaway 10y ago

It is impossible to build anonymity system without some sort of centralization due to possibility of Sybil attack. You need some trusted entity beforehand, otherwise your ISP can just simulate the whole network for you and never let you connect to the real network without you even noticing this.

sangel 10y ago
I'm not sure that I agree with your point. DC networks (see David Chaum's work and also Dissent by Corrigan-Gibbs and Ford) have no centralized components and provide stronger anonymity than Vuvuzela. However, they are not very efficient for large user bases. This is different from being "impossible" though. The attack that you are describing seems to be a denial of service rather than a privacy violation. Centralized systems have similar issues though (your ISP could simply block packets to such system, one of the malicious centralized servers could refuse to process messages, etc.).