There was recently a post to the sks list prompting discussion regarding the use of PGP and SKS as a distributed web of trust for an alternative currency system called “Bitcoin.” This reminds me of a project I worked on in the early ’00s with the late Jeff Fairhall and Thomas Greco.
Anyhow, I mumbled some things on IRC about my thoughts:
08:23 < cj> nanotube: I got your email on the sks list 08:32 < cj> nanotube: the reason SKS keyservers work at this point is because there is little interest in PGP WoT 08:32 < cj> or PGP in general 08:33 < cj> cjac@pki:~$ df -h /var/lib/sks 08:33 < cj> Filesystem Size Used Avail Use% Mounted on 08:33 < cj> /dev/xvda2 14G 9.0G 4.2G 69% /var/lib/sks 08:34 < cj> if a major monetary system were to "piggyback" on the existing network, maintenance of pub keys would become unmanageable 08:34 < cj> nanotube: read through the sks archive with an eye toward database size 08:36 < cj> there are a total of a bit more than 3M keys in the db at this point. 08:36 < cj> http://keyserver.colliertech.org:11371/pks/lookup?op=stats 08:38 < cj> My database becomes corrupt every 3 months or so and I need to re-build it. This may just be user error, and probably is. However, I do not seem to be the only one who suffers from this problem. 08:40 < cj> Assuming that there are on average about 5 keys in the db per participant, that means the 9G of key data represents 600K humans. 08:42 < cj> which is roughly 0.000085719% of the world's population 08:43 < cj> if we want to support the other 100% of the population, we need to implement intelligent sharding or improve the efficiency of the data store 09:04 -!- OneFixt is now known as Guest66546 09:06 -!- Guest66546 is now known as OneFixt 09:08 < cj> note that operating a key server which stores anything less than the full set of public keys compromises the integrity of the system. The primary objective of the key server is to be a complete store of the set so that there is no central authority. 09:16 < cj> from the wiki page: "Since the web of trust node keys will over time grow long with a bunch of UIDs, it is likely that you may not want to use your regular key for this purpose, and would probably want to create a separate key. If you want to tie your regular PGP identity to this key, you can simply cross-sign your regular key with your web of trust key." 09:18 < cj> this assumes that there is an infinite amount of storage on each SKS key server. If everybody's key will over time grow long with a bunch of UIDs", then we will see a very large number of very large keys. 09:19 < cj> I recommend that bitcoin participants manage their own SKS pool while developing the proof of concept. This will reduce the noise caused in the public pool. 09:20 < cj> and will give the developers an understanding of the implications of their design decisions 09:22 < cj> here are some thoughts I had on the subject a decade or so ago and RMS' responses: 09:22 < cj> http://web.archive.org/web/20030812201116/http://gnubucks.com/impressions/rms.html