159 lines
8.7 KiB
HTML
159 lines
8.7 KiB
HTML
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<!DOCTYPE html>
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<html lang="en">
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<head>
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<meta content="text/html; charset=UTF-8" http-equiv="content-type">
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<style>
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body {
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max-width: 30em;
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margin-left: 2em;
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}
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p.center {text-align:center;}
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</style>
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<link rel="shortcut icon" href="../rho.ico">
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<title>Functional Specification</title>
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</head>
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<body>
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<p><a href="./index.html"> To Home page</a> </p>
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<h1>Functional Specification</h1>
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<p><br/>
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</p>
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<p>A functional specification is a pile of mockups of the user interface,
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telling a story of what the software will do for users, explaining how the
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program will behave externally. </p>
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Humans have been identifying themselves with shibboleths for thousands of
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years, and frequently killing each other in large numbers on the basis of
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shibboleths.
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<p> So it seems to me that the way to go is to have the front end, the user
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interface for most users, shibboleth based (username and password), while
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the backend uses public keys, and all the other tools at our disposal, to
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make shibboleths resistant to dictionary attacks and man in the middle
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attacks. The user, therefore, should ordinarily control the private key by
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username and password. </p>
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<p> Here is one such proposed system, intended to implement Zooko’s
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triangle: </p>
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<p> The end user creates an account with username and password on an
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identity server, which may be running on the cloud, or on his company
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server, or on his home network. He gets the hash of a rule identifying
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public keys that are valid for him, and his username, and how to contact
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him while he is logged in. </p>
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<p>Now if any user actually sees that hash, contact information, and so
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forth, they will reel back in horror. It absolutely has to be
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hidden, or else users will boggle. We stick it in the avatar icon,
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and/or reference it by the petname.</p>
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<p> Many people can have similar or seemingly identical avatars, and people
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on different servers can have the same nickname, one’s nickname being
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one’s username on a particular identity server. </p>
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<p> When he is logged in to that identity server, he can message other
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people, and other people can message him. To message someone, you need
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their avatar containing their public key. Any such avatar will be assigned
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a petname that is unique for any end user, so if someone communicates with
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two different people, with two different public keys, they will always be
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identified as having two different names, even if they both have same
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nickname. </p>
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<p> So if I get two people whose nickname is Bob, my software will insist on
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me differentiating them with different names before I can message them. </p>
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<p> The end user should have on his local computer and on his identity
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server data structures that looks like a browser bookmarks list, except
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that the favicons can be quite large (can be user avatars), the entry
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generally contains public key information about the target (or the hash of
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the rule identifying public keys valid for the target), and the entry may
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contain username and password information for mutual identification, after
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the fashion of otr. </p>
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<h3>Communicating public keys:</h3>
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<p> The problem is that you want to tell someone over the phone, or on a
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napkin, or face to face, information that will enable his client to
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securely obtain your public key and network location so that end to end
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secured communication can take place.</p>
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<p> Also a chatroom’s public key and network location.</p>
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<p> We do not necessarily protect against security agencies figuring out
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which public key is talking to which public key. That issue is out
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of the scope of a functional specification, but we somewhat reduce the
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usefulness of this information by allowing people to have lots of public
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keys. So you probably have one key for activities that show your
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unusual sexual preference, another key for job related activities, another
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key for tax evasion related activities, another key for gun running, and
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yet another for attempts to overthrow the regime.</p>
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<ul>
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<li>
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<p> Face to face:</p>
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<blockquote>
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<p>Identifying information is nym, face, and location.</p>
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<p> Recipient looks up the nym, sees a bunch of faces grouped by
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geographic area. Geographic are usually, but not necessarily,
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has some relation to users actual location, and may be very
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specific, or very broad. It is a tree. One guy may
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locate his face at the node "North America", another at the node New
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York, North America. You may, of course, employ a well known
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cartoon character or movie star as your avatar instead of your
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actual face. Fictional places are permitted, but to
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avoid filling the namespace, not on the tree that represents the
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real planet earth.</p>
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</blockquote>
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</li>
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<li>
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<p>Over the phone.</p>
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<blockquote>
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<p>Recipient looks up phone number. Finds a bunch of named keys
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associated with the phone number – usually one key or a quite small
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number of named keys.</p>
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</blockquote>
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</li>
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<li>
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<p> Web or email.</p>
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<blockquote>
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<p>Send a link that contains a 256 bit identifier, but the UI should
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not show anyone the identifier.</p>
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</blockquote>
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</li>
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</ul>
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<p>The ordinary user by default finds himself using at least one key for
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face to face key introductions, a different key or keys for phone
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introductions, and yet more for web or email introductions. If he is
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clever and reads the manual, which no one will ever do, he can use the
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same key for multiple purposes.</p>
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<p> All of these named keys have the same behavior when you click on them,
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they are intended to be perceived by the user as being the same sort of
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thing.</p>
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<p> He can use the link, the named key, to attempt to contact, or buddy it,
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or bookmark it.</p>
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<p> The identifying link information looks like a web link, and is the
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nickname of the public key. By default the nickname is the
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petname. The user is free to edit this, but usually does not.</p>
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<p> When he attempts to contact, this automatically buddies it and/or
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bookmarks it.</p>
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<p> When he finds a named key, he may "bookmark" it, together with one of
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his own private keys – it goes into a datastructure that looks like, and
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works like, browser bookmarks. He can also put it in his buddy list.</p>
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<p> When you look at an item in your buddy list or bookmarks list, You see a
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pair, the other guys key identifying information, and your own key
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identifying information. You don’t see the keys themselves, since
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they look like line noise and will terrify the average user.</p>
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<p> When you click on one of these bookmarks, this creates a connection if
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your key is on the other guy’s buddy list and he is online. You can
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chat, video, whatever, end to end secured. Otherwise, if you are not
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on his buddy list, or he is not presently online, you can send him
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something that is very like an email, but end to end secure.</p>
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<p> When you send a bunch of people a text communication, chat like,
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chatroom like, or email like, they are cc or bcc. If cc, all
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recipients of the communication get links, which they can, if they feel so
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inclined, message, bookmark or buddy.<br/>
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<br/>
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Text communication software vacuums up and stores all links, so if you get
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an incoming communication from someone whose public key you have not
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buddied or bookmarked, the software will tell you any past contacts you
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may have had with this public key.<br/>
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<br/>
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Buddied public keys are white listed for immediate online communication,
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Bookmarked and buddied public keys are white listed for offline text
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communication, public keys with past information about contacts are grey
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listed, public keys with no previous contact information are blacklisted.<br/>
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<br/>
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Because of automatic blacklisting, to contact, you have to <i>exchange</i>
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keys.</p>
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<p style="background-color : #ccffcc; font-size:80%">These documents are
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licensed under the <a rel="license" href="http://creativecommons.org/licenses/by-sa/3.0/">Creative
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Commons
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Attribution-Share Alike 3.0 License</a></p>
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</body>
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</html>
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