Re: [Mldonkey-users] Questions about the edonkey protocol

[Norbert LATAILLE]

> 1. quick and easy
> 2. better way

I started to work on it, by first hacking read_first_message to create
the client on the fly when I get the connection from the firewalled
client. 

> A question from my side:
> I tried something like this
> http://mail.gnu.org/pipermail/mldonkey-users/2002-December/001704.html
> (but it won't work with edonkey as the servers only support callbacks 
> only for lowid
> hosts).
> Do you think this may be possible with overnet?
> For edonkey (and probably overnet) a firewalled user can reach someone 
> else but is not
> reachable by others.
> My case is vice versa: My client can be reached by everyone but can't 
> connect to every port.
> What I think of is to issue the search request with some sort of *can't 
> connect to these ports*
> option and get a referring bcp for all hosts using these ports.


What I understand is that SYN packets to some external ports are
filtered by your network. I fear that overnet can't support your idea,
because you cannot choose if you want a direct or indirect connection :
it's decided at boot.

---
Here is a small description :

1/ 
At boot, a new peer (A) chooses one random peer on the network (B) and
sends a test packet with its TCP port. This refering peer (B) returns a/
the public IP of A b/ the state of the peer (firewalled or not)

2/
If (A) is firewalled, then (B) is known as the refering peer of (A) and
holds an open TCP connection with it. 
- Every file published by (A) is then in the bcp://md4:ip_of_B:port_of_B
form.
- (A) publishes in the distributed hashtable at its MD4 address the
ip:port of (B)

3/
If a peer wants to get a file from (A) it can ask for a connection by
sending it's TCP port in a 18h/19h/1Ah packet to (B).
---

It seems that you can benefit from sources of firewalled overnet
clients, but not normal ones...

Norbert