[syslinux] dynamic tftp content?

[Craig]

H. Peter Anvin wrote:
>> Has there ever been any consideration to allowing the tftp server to 
>> provide dynamic content?
> Yes.  The protocol makes it difficult.

I was really hoping you wouldn't say that...


> You pretty much have to guarantee that the contents is generated in a 
> fraction of a second, or your client will most likely flood your server.
> 
> The problem is that in order to be able to answer a tsize query you have 
> to know the full size of the output.  However, since TFTP isn't 
> guaranteed to distinguish between an RRQ resend and a new request 
> (pxelinux will make the distinction, but it's hard for the TFTP server 
> to make use of it), so you have to have a reply before the first request.

What if you sent back a "more coming" message. (Not sure if that's what 
you mean by the "pause" option.) My thinking is that that message could 
always be the same length. But, I don't know enough about the tftp 
protocol to know if that's easier or not.

> I have a proposal for a TFTP "pause" option and opcode, but I would have 
> to (a) implement it, and (b) write it up as an RFC, (c) figure out how 

Let me know if you need any help. My c is rusty, but it was decent once 
upon a time. :)

> to get it through IETF, which like to pretend TFTP doesn't exist.

:)

Do you happen to know why PXE requires tftp? Wouldn't it have made more 
sense to do some kind of http or ftp download? (I would think http would 
be a little easier.)