Requirements¶

TBD

Without defining the requirements first, any software we write will have to be re-written many times.

What to implement¶

~~pEp engine transport for messages~~

Add mixnet capabilities to SMTP transport

to hide metadata, in this case, Email headers YES Email from the last node to the receiver will have the headers that pEp adds/removes/modifies
- to a third party observer? (unlinkability, possible correlation attacks) YES
- to the receiver? (sender anonymity) NO
  - what about the sender Email From: header when the receiver wish to reply to the sender?
  - what about the sender Email Received: header?, that might disclose sender geographic location?
  - what about the sender Email Date: header?, which discloses the time when the Email was sent
  - untraceable return address? (receiver can reply but doesn’t know the location of the sender?)
- to the sender? (receiver anonymity): NO the sender does not know which recipient has received the message.
to be compatible with existing Mixmaster network? Mixmaster network still works, but small anonymity set, so NO
to reuse the pieces that pEp or partners have developed? CAN
to not to reinvent the wheel? SHOULD
to have a system that anyone can extend? (scalability)
- how to convince others to run nodes? > by the extra capabilities pEp offers > intial nodes can be run by friends

who is going to use MixMailer?

estimated number of users/clients?:

pEp scales to billions of users

It should be a solution that is usable by the “end user”, not only by the nerd:

transparent to the user

pEp client (frontend), eg. Thunderbird plugin:
```
pEp client is part of the engine
```
pEp engine (backend), would route the Email to MixMailer