Add an explaination on URLs vs URNs

parent bab0200e
......@@ -135,6 +135,8 @@ We can then use that to federate a message to Bob.
* What's going on?
** URLs aren't the only URIs
That's all great, but how is this different than any other ActivityPub
instance?
How do we even know that things were sent securely?
......@@ -176,6 +178,27 @@ its Wikipedia page:
they identify ceases to exist or becomes unavailable.
#+END_QUOTE
I really struggled with these different names when I heard them, so
here's my short handy guide:
- *URIs:* The broadest category of universal identifiers, of which
URLs and URNs are both subcategories. Different schemes (eg
=https:=, =urn:=, =ftp:=, =file:=, =ipfs:=) signal how we might
retrieve and interact with the resources at those addresses.
- *URLs:* Signify some sort of "living" resource that we can imagine
"living" somewhere, and that location is responsible for their
content. =https:=, =file:=, and =ftp:= are all examples of URLs.
A subcategory of URI.
- *URNs:* Not tied to a specific location. Hashes of content
like =urn:sha1:= are good examples of this, and (usually) so are
most =ipfs:= URIs.
A subcategory of URIs (in contrast to URLs).
Don't worry too much about memorizing these names... the general idea
of some URIs being "living in a specific place" and other objects
being "persistent and able to live in many places" is the key here.
An example may help.
Alice could host a picture of a cat live at =https://catpics.example/pics/mycat.jpg=,
but that could always go down.
If the cat picture became very popular, Alice would be responsible
......@@ -235,10 +258,14 @@ more sense:
This is all very good and well, but what does it look like during
federation?
** Federating out encrypted, content-addressed content
** Retrieving that content
* Verify it yourself!
* Problems with this demo
- urn:sha256 isn't actually specified yet, but it probably should be
- urn:sha256 isn't actually specified yet, but it probably should be.
- At the time of writing, the magenc extensions to the magnet scheme
aren't used by anything in production yet.
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment