by Darius Kazemi, August 23 2019
RFC-235 is titled “Site Status” and authored by Ellen Westheimer of BBN. It's dated September 27, 1971.
The technical content
This RFC is the first of what is to be a series of reports from BBN on the status of hosts on the ARPANET. They plan to randomly attempt to connect to hosts from a Terminal IMP and collect data on whether they are able to connect, what sorts of errors were returned if not, etc.
They will not attempt to connect to hosts that are simply clients and not servers, hosts that are known to be offline, and hosts that are only meant to collect statistical data on network performance.
There are two lists included in the RFC.
The first is a list of each host, the computer at the host, the name of the site, the main person to contact at the site, and the host site number.
The second is a list of dates and times that BBN attempted to connect to a given host, and they note the following statuses of each host at the time:
- Open (online)
- Dead (totally inaccessible)
- Refused (host refused the request to connect, issuing a “close” in response)
- Timed out (no response but not dead)
- Half open (connection was made but nothing worked after that)
Slightly less than half of the 120 connection attempts that BBN made to remote hosts are labeled “D”, for dead! Here's my count:
- 56 dead
- 33 open
- 17 timed out
- 10 half open
- 4 refused
Only 33 out of 120 connection attempts, or a measly 27.%, resulted in a successful connection.
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I'm Darius Kazemi. I'm an independent technologist and artist. I do a lot of work on the decentralized web with ActivityPub, including a Node.js reference implementation, an RSS-to-ActivityPub converter, and a fork of Mastodon, called Hometown. You can support my work via my Patreon.