This describes the global, interconnected, Chaosnet. If you just want to set up a local Chaosnet, please see here for instructions.

A Chaosnet bridge runs on (the IP, IPv6, and Chaos) host MX12.Victor.SE (also under the alias Router.Chaosnet.NET), accessible by UDP or TLS on port 42042, or using IP protocol 16 (over IPv4 or IPv6), as Chaos host 3040.

The MX12 bridge

• routes packets between connected networks,
• sends and processes Chaosnet routing (RUT) packets to connected networks (and CHUDP hosts), and
• responds to the contact names STATUS, TIME, UPTIME and DUMP-ROUTING-TABLE, among others.

See here (or MIT AI Memo 628) for more details about the protocols.

To connect to the “global” Chaosnet, you need to register a compatible Chaosnet address. To connect using Chaos-over-UDP, you need a stable IP address and a compatible Chaosnet address, and if you connect directly to MX12 using CHUDP, I need to open the firewall there. To connect using Chaos-over-TLS, you do not need a stable IP address, but you do need a certificate issued by my Certificate Authority (see here for instructions).

A single host can be connected if it can use a non-local link layer, i.e. Chaos-over-{ TLS, UDP, IP, IPv6 }. To connect a host which only uses Ethernet or unix sockets, you need to set up a local network and a cbridge (see next section).

To get a compatible Chaosnet address, send an email to bjorn@victor.se and tell me

• the name of the host, including its domain (but do not just invent domains - see below),
• what kind of host it is (ITS? Lambda/Explorer/Symbolics Lisp machine? cbridge?), and
• on what IP it is (IPv4 or IPv6). (If you don't have a stable address, you need to use TLS).

You should (most likely) have an address on subnet 6 (range 3001-3377). (Ideally, run a cbridge and put your local hosts on a subnet behind it - see configuration examples below.)

In emergencies, you can list occupied addresses e.g. by host -c ch -l ch-addr.net. dns.chaosnet.net and pick a free one, but don't forget to tell Björn as soon as possible. And pick one on net 6 (range 3001-3377).

Set up a cbridge to handle your local network. Tell Björn the things as above about your cbridge host, and also ask Björn for a separate subnet to use (in emergencies, pick a subnet between 17 and 171 octal, avoiding those listed below - and don't forget to tell Björn!). Do NOT add all your local hosts to subnet 6, but only the cbridge. See configuration examples below.

To add DNS info, send Björn

• the names of the hosts, including domains (but do not just invent domains - see below),
• what kinds of hosts they are, and
• their Chaosnet addresses on your subnet.

I'm thinking about this. The old WHO-AM-I and TI-WHO-AM-I protocols are not quite sufficient, and full-blown DHCP is a bit overkill.

You can ask to get added to (a subdomain of) Chaosnet.NET.

I am very reluctant to¹⁾ add Chaosnet DNS info for domains none of us are in control of, since they might discover and complain, with possible legal and financial results.

For configuration examples, please see also here.

The following subnets (in octal) are used/registered or special. See also AI:SYSHST;HSTNET > for historical use.

Note that while there are technically 255 subnets (excluding 0), only 172 (octal) different nets fit in a routing table pkt, and the DUMP-ROUTING-TABLE protocol only lists subnets up to 172.

Special: the TI-WHO-AM-I protocol broadcasts on that subnet to find out its address, and it is probably often default for old Real machines, e.g. Lispms. Previously used for the Chaos-over-Ethernet at Update, because the old Symbolics 3600 had address 401.

This is for hosts connected to MX12 by Chaosnet over UDP (CHUDP), IP (v4/v6) or over TLS, mainly ITS hosts and cbridge processes.

Side note: MX12 is named after MX-11, which was a Chaos gateway at MIT; one of its addresses was 3040 which is on net 6; address 3040 is the default for routes in ITS, see SYSTEM;CHAOS >.

Special: Default subnet for LMI machines; 3412 used by LMI machines for “Amnesia” (hosts that don't know their address). BVs home network, over Ethernet, IP, and Unix sockets.

Allocated for Bogodyne Metatechnics LLC.

AMS' home network (AMS.Chaosnet.NET).

Eric Swenson's network.

Used by SJ.GEWT.NET(?)

In order to minimise address collisions and routing problems, this subnet has been reserved as a private, non-routed subnet. No routing information about that subnet should be sent outside that subnet, no packets from that subnet should be sent to other subnets, and any packets received from that subnet on another subnet should be dropped.