Hi All,

I am implementing a PPP,TCP/IP stack for an embedded device and have
run into a brick wall.

Everything seems to work *except* I cannot seem to establish a
connection with a firewalled server.

I can
* Establish a PPP connection with both a dial-up ISP and WindowsXP
Incoming Connection
* Ping the whole route up to the firewalled server from either (modem
dialup or direct XP ) connection.
* I can ping my embedded device over either connection
* I can invoke a Socket and make a HttpRequest to a local server when
connect using the directXP connection
* I can get an Echo Response from the routers all the way up to the
firewalled server
* I can get a SYN+ACK back from non firewalled server

However.. from the firewalled server I need to use I
* get no ping
* get no echo
* get no SYN + ACK to my TCP SYN request

The ping and echo I can live with if the firewall is simply dropping
ICMP packets.

>From what I can tell it looks like there is some special magic about
the way a SYN packet must be formatted for the firewall

Does anyhow have any inside knowledge on what if any special rules need
to be abided by when attempting to connect with a server behind a
firewall?

THanks in advance.
James Caska