From 5e844aca2081ef6d2e9615eea24b8a9d56f41c19 Mon Sep 17 00:00:00 2001 From: Bryan Newbold Date: Tue, 28 Nov 2017 23:34:54 -0800 Subject: notes on DNS, DHT, etc --- notes/network.md | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 notes/network.md diff --git a/notes/network.md b/notes/network.md new file mode 100644 index 0000000..85b97ee --- /dev/null +++ b/notes/network.md @@ -0,0 +1,51 @@ + +### dat-specific configuration + +Default servers are specified in the `dat-swarm-defaults` module. As of +November 2017, they are: + + Domain (for mDNS, centralized DNS): + dat.local + + DNS Servers (centralized lookup): + discovery1.publicbits.org + discovery2.publicbits.org + + DHT Bootstrap Servers: + bootstrap1.publicbits.org:6881 + bootstrap2.publicbits.org:6881 + bootstrap3.publicbits.org:6881 + bootstrap4.publicbits.org:6881 + +### mDNS and Centralized DNS Discovery + +`dns-discovery` node module. + +Refresh period: 1 minute + +Take the first 40 hex characters (lowercase; 20 bytes if decoded) of the +discovery key (a BLAKE2b hash) instead of a SHA1 hash (which is what bittorrent +uses). Prepend this to the domain (`dat.local` in the case of dat). + +There are both SRV and TXT records. SRV is straightforward, a response like: + + 0 0 44113 172.19.0.4. + +TXT uses some un-documented token scheme... maybe mostly for mDNS, to update or +"unannounce" records? Eg: + + "token=kZabfUWLUw5A4E/EXM3+ka7UybMN95QJjqPk1iGmb0M=" "peers=rBMABKxR" + +Example lookup: + + dig @discovery1.publicbits.org 905fd1b6504698425e8bec3dbb77d757e281d505.dat.local SRV + +Note that you might need to do lookup on *both* servers? Results can be +different from either individually. + +### DHT Discovery + +`discovery-channel` + +Refresh period: 10 minutes + -- cgit v1.2.3