-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 A couple of people have emailed me and asked exactly what the resource requirements for a keyserer are. I asked Randy Harmon, the administrator for certserver.pgp.com, to see if he could answer that question for me. His response is below. Thanks, __ L. Sassaman System Administrator | Technology Consultant | "Common sense is wrong." icq.. 10735603 | pgp.. finger://ns.quickie.net/rabbi | --Practical C Programming - -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Many parts of the answer to that question: - The replication infrastructure affects the bandwidth used. Take a 10-node keyserver network. If one is the master for accepting keys, and 9 accept replications from it (without cross-replicating), then the bandwidth used is far different than if each replicates all changes it receives to each of the other 9. In the first case, each one would replicate its news to the master, which would replicate back to all 9 (or 8, arguably). - Keyservers do get out of sync with each other (replications not arriving, replicas unavailable) and should be periodically cross-sync'd. Databases can also become corrupted and should be periodically rebuilt (combined with cross-syncing, ideally). These rebuilds help make up for the possibility of failure in the more-efficient replication mechanisms, and should probably use a "pull" approach rather than a "push" approach. So the master server could pull keysets from its replicas, rebuild and merge its own database with the keysets from others, then send a notification that a database update is available. This approach would use, in the 10-server example, 1.2kb per key x 2 transmissions x 9 servers - The disk hardware should be capable of withstanding the search volume (depends on the number/types of searches performed) and of rebuilding the databases without major impact on search performance. I'd suggest 8-15 gigs of FREE space, beyond ~6 gigs for the main database. Single drives are OK for low search volume and low search performance. Larger database means more disk space, approximately linear. Modulo differences in indexing techniques, as the number of keys continues to grow very large. - Day-to-day bandwidth is a function of the number of replications triggered by a key add/update, the number of keys added/updated (roughly 4/3 * 1.2kb per key added/updated) and the number/types of searches performed. We currently receive about 20,000 searches per day (5 keys returned per search, on average), about 1500 adds, and about 250 updates. For today's volume with the more efficient replication approach discussed above, the master server would consume: Searches: 100,000 * 1.2k * 4/3 radix-64 overhead = 160 MB Adds/Mods: 1750 * 1.2k * 4/3 overhead = 2.8 MB Replications: 2.8 MB * 9 = 26 MB If we assume 10 times the volume as today (1.1 million keys on the server), and 10 servers to balance the search load, then the bandwidth for each server would be roughly: Searches: 160 MB Adds/Mods: 28 MB Replications: 28 MB outgoing 280 MB incoming ============= 496 MB/day 15 GB/month Multiply by 10 for 100,000,000 keys. Randy - - -------- Randy Harmon <rjh@pgp.com> Administrator, certserver.pgp.com Engineer, PGP Keyserver PGP KeyID: 0x5cb7b7f2a0aa5c1e - -----BEGIN PGP SIGNATURE----- Version: PGP 6.5.3 iQA/AwUBOVp8UVy3t/KgqlweEQKvdACfWZg0IP0TM9L95y5Kr7uRK9rIsJIAoOw6 JmG9SvmaLuGF369Z5PQF3Jfy =QbGa - -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- Comment: OpenPGP Encrypted Email Preferred. iD8DBQE5Wn8TPYrxsgmsCmoRAlMcAJ0cNO/FmBjVEMOsYpP7IzYbSR0C8wCggvhA GpaC1VIyTtUZrzigZl2JyeA= =mlcy -----END PGP SIGNATURE-----