One of the features of IOTA is that sub-tangles can be constructed and then attached to to the main tangle in the future.

With IRI version 1.5.2, how does the prevention of lazy tip selection change the tangle's partition tolerance?

For Further Reference, please see these resources below

Original IOTA features list on BitcoinTalk

[IOTA solves] Partition Intolerance

Blockchain-based currencies are unable to survive long-sustained partitioning of the network because this may lead to reversal of a large number of transactions. It is also impossible to initiate an intentional partitioning in cases when it is required.

A quick-easy reference to it by @zauz here on iota.stackexchange:

When would it be required to intentionally partition the Iota transaction graph?

A @medium article on it called Sharding the IOTA Tangle Effectively.

Indeed, this is even covered in an AMA here:

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    "sub-tangles can be constructed and then attached to to the main tangle in the future" can you add the link to sources please ? – ben75 Jul 23 at 11:38
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    The linked source is a theoretical approach of tangle partitioning, and don't reflect the strategy of the IF regarding tangle partition. AFAIK, the only official publication briefly presenting partition in the tangle is this one about economic clustering. – ben75 Jul 23 at 23:01
  • I think it's better to add your own answer (referring to the github issue) instead of editing the question. Just to keep things in a clean structure. (The question remains perfectly valid as it was) – ben75 Jul 26 at 13:53
  • I always thought is was a core strategy of the IF regarding tangle partition. Paul Handy's issue is not necessarily the answer. It just acknowledges that there are serious issues afoot with the changes. There may be other issues and someone might also address them in an answer. – Austin Powers Jul 26 at 14:02

IMO, a distinction should be made between different partitioning scenario.

  1. Accidental/occasional partitioning

It's the situation where a portion of the network is temporary disconnected for a relatively short period of time. Participant can still submit transactions to the disconnected tangle and when the disconnected tangle is back online, transactions will simply be included in the main tangle.

Changes in IRI 1.5.2 will impact the acceptable offline period (previously it was limited only by snapshot time). i.e. an "accidental partitioning" cannot last for a too long period of time, otherwise a re-attachment of all transactions of the disconnected tangle is required. (i.e. if the accidental partioning last for too long, IRI 1.5.2 will interpret this situation as a side-chain stiching (see point 3 below) ). (see also the related issue on github)

  1. Intentional partitionning

This is economic clustering . The details are still unknown at the moment.

  1. Side-chain stiching

An actor use a customized tip selection algorithm to build a side chain and try to include it in the main tangle later. We saw that this massive sudden appearance of transactions build on top of a very old milestone was causing problems for all participants using a fair-tip-sel.

IRI 1.5.2 should fix this kind situation.

  • Why is it relevant why the partitioning happens or is required? The idea is that the tangle is supposed to be agnostic to this and all the PR material published by IF says "No worries - everything is OK". IMO - the IF just reneged on a key feature of the platform and this also effects offline transactions and Flash Channels too. – Austin Powers Jul 24 at 13:54
  • Well, you quote David Sonstebo in your question, and he just explain that "Not everything is OK". I'm not a specialist of the Flash Channels, but I don't see how the changes in IRI 1.5.2 may have an impact on this. (Flash channel start with a transaction to a multisig, ends with a transaction from a multisig. Last transaction don't need to approve the first one) – ben75 Jul 24 at 14:26
  • Economic Clustering doesn't exist right now and isn't even detailed in any useful manner. Nobody knows how it will work. It isn't productive to mention it in relation to current issues. – Austin Powers Jul 25 at 2:05
up vote 0 down vote accepted

With IRI version 1.5.2, the prevention of lazy tip selection removes the ability for the tangle to accommodating offline transactions and subtangles. This is one of the primary and foremost advantages to the Tangle construct.

For reference to this, please also see Paul Handy's (IOTA Developer) github issue:

False-Positive Subtangle Rejection

Large subtangles are currently skipped if they fall below a node's configured maximum depth (counted in milestone subtangles). I would suggest that while this reduces the amount of tying in of 'stale' subtangles, it is detrimental and ultimately goes against one of the main advantages of Tangle - that offline subtangles may merge in the future.

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