Ämne:SV: [dcdev] Anyone still alive?
Från:Gustaf Räntilä <[email protected]>
Till:"'Direct Connect developers'" <[email protected]>
Hello all, If adc finally is moving into 'stable' state, I have a few concerns... First of all 2.1 states: "All text data in the protocol that is not entered by the user, including protocol names, extensions etc may only contain viewable characters that may be encoded by one byte in the UTF-8 encoding (ASCII codes 33-127). Although the protocol is case-sensitive, names distinguished only by case are disallowed (upper case is preferred)." Here, "names" are nick-names I suppose. Should they (as they once Are "entered by the user") be able to contain multi-byte UTF-8 chars or single-byte > 127? I believe that's what "All texts must be sent as UTF-8, including file lists, searches, nick’s, hub lists etc." means. In this case, hubs must include full UTF-8 supported case insensitive matching I suppose... This is not a complaint or anything; I just wanted to be clear of the issue that true Unicode enabled string functions are required in ADC generally. As in contrast to 'regular DC' were currently, any non-utf-8 enabled string function will (probably) do (no matter what internal string encoding is used, for instance with dc++ gui being Unicode nowadays), since UTF-8 is a nice encoding, and since DC doesn't support anything but 'ACP'. So relying on current implementation when it comes to string functions isn't a good idea I suppose. (Just a hint for any "ADC-developer" if I have got it all right.) Secondly, I've said this before (far over a year ago) I like the idea of encrypting the traffic, and I barely see theoretical limitations to this, even though p2p data speeds are 'high' nowadays. I know of certain internet providers (universities for instance), that have taken action against users simply because of filenames in shares (that are being sent clear-text as bz2 filelists). They are using programs analysing this kind of traffic automatically (you all probably know this, I know). This is not 'our' problem, but I think it's not more than fair to try to develop a 'native' support for an encryption base in the main protocol. P2P encryption is probably not very difficult with individual key-pairs or anything similar, but what's probably not so easily done is search replies (and eventual client-hub encryption). Maybe something like the GPA/PAS-routine could be done for client-hub ciphering to avoid usual encryption keys (if this is heavy for hubs to generate/encrypt/decrypt). If encryption becomes native, a key-propagation in the search message should be easily implemented, so the clients encrypt the search reply with the given key. Note; if this is Not natively implemented in the base protocol, then future implementations are a lot more difficult, since there is no exchange of "extended client features" in the usual client2hub communication. /There are no way to know another clients public key/ in other words. This could be sent in a wider INF for sure, but I'm not certain it would be any more efficient, so "making room" for this natively could be a good idea. I have the feeling that encryption isn't something most of you are interested in, but I still want to know how you feel about it. And I would like feedback on my urge for the native support of (I agree, maybe _future_) key exchanges in the base messages presented by the protocol. /Gustaf aka 'Opera' (and yes, I'll convert from outlook to thunderbird one day) -----Ursprungligt meddelande----- Från: [email protected] [mailto:[email protected]] För Jacek Sieka Skickat: den 28 december 2004 17:11 Till: 'Direct Connect developers' Ämne: RE: [dcdev] Anyone still alive?
I recently went through the whole 0.8 draft (but I only skimmed the attachment you sent). It looks good, but one feature I am missing is; if one client via a hub wants to request a connection (CTM) and the requesting party cannot connect (connection refused, firewalled/timeout or whatever).
A DSTA will do just that, adding an error type for it probably makes sense...
There should be a notify-message that the connection could not be established. (Only if the connection attempt had a token). This can for example be done with a RCM using the same token back to the origin. This way both parties can be aware that the connection cannot be made, not just the connecting party. And thus, this aids network diagnostics.
Extending this, a passive client can send a RCM to another passive client which will answer with RCM and the same token. Now, both clients know that they are passive and cannot communicate directly.
Client passivity can already be deduced from the INF Another thing I'm considering (suggested by some dcdev people =) is a publish-subscriber message type that gets a channel id and where the messages are only sent out to the clients that have subscribed. This could be used by extensions for instance to only send out a particular command to clients supporting a particular feature...the only thing that worries me is that it potentially makes the hub a bit more complex...on the other hand, almost all message passing protocols have these three types, direct, subscriber and broadcast so... /J-- DC Developers mailinglist http://3jane.ashpool.org/cgi-bin/mailman/listinfo/dcdev-- DC Developers mailinglist http://3jane.ashpool.org/cgi-bin/mailman/listinfo/dcdev