[Nel] A small document for your consumption

[Vincent Archer]

I'll answer both posts at the same time...

According to Thierry Mallard:
> Possibly this can be partially avoided by providing your own DN Server's IP ?
> (dunno precisly how the client would connect to it, but still...)

There are two ways you can find out a server:

1) Hardcode the IP address (then, you cannot move the server)
2) Use DNS for dynamic IP (then, the hardcoded address is the root of the
	DNS tree - which, hopefully, changes even less often than we will)

You can't specify your "own DNS". Using that is basically the same as
using method 1: you still have to put a server at a static IP that gives
you off the dynamic IP.

> > 2: The client submits its login, password, and system capabilities.
> 
> In plaintext ?

If we assume the link has a crypt method in it, why not.

Three possible methods for password submission

1) Plaintext, assuming the connection has a form of crypt in place
2) MD5/crypt password. Spoofable, since:
	a) You can capture the MD5/crypt string
	b) You have the client source, so can hack it to send the static
		crypted password instead of crypting the - unknown - plaintext
3) MD5 for a dynamic challenge. A good example: the server sends you the
	current date when you connect, and you use that date as the first
	bytes of the MD5 digest.

> > 4: The client selects the world it wants to log on, and submits the IP address
> >    of its world service to the LS.
> 
> Would it be good if the client could select several worlds ?
> (then the negociation following could use this to get a good WS)

Not good. Typically, the client will connect to the world the player has
a character he wants to play today :)

However, the client may use the IP addresses of the WS to ping them and
figure out which connection is better (when selecting its first world).

> So the WS is (or can be?) a load-balancer to all the FES in a given world ?
> -- the balancing being done at network level, not process level --

The WS *is* the load balancing mechanism. Since he's aware of all FES
up and running, and knows their load right now, he's best suited to
determine which FES can afford to manage a new character.

> I wonder if it couldn't be more interesting if the client disconnects from LS
> _after_ having initiated the connection to the FES. Then, if something goes
> wrong, the client could goto 4 directly.

Hmmm, that might be good, yes.

-- 
Vincent Archer                                         Email: archer@nevrax.com

Nevrax France.                              Off on the yellow brick road we go!