Hi guys,
When i upload "DHCPChatServer"(the one from Examples) to the arduino(i am using uno) and set ip, mac and gateway, configure my local are connection settings and then reset the shield all i get is "unidentified network". :o What's so wrong ?
I really appreciate any help you can provide.
Can you ping 192.168.1.177 from the PC?
hmm..
Are you connected to a router on the localnet?
Generally i use router for my main internet connection, but when i am with the arduino ethernet shield i connect it directly.
but when i am with the arduino ethernet shield i connect it directly.
Directly to what?
PaulS:
Directly to what?
Directly to my laptop's lan card.
crit1s:
Directly to my laptop's lan card.
Why? Why not connect the Arduino to the router, too?
PaulS:
Why? Why not connect the Arduino to the router, too?
Yes, it works when i connect it to the router, but in my project the arduino wont be connected through a router.
You might need a hub or switch. There have been reports the Wiznet ICs don't do well when connected directly to a gigabit port. They seem to do ok with a 10/100 port tho. Is your network card in the PC a gigabit card?
Versions of Windows later than XP / Server 2003, utilise the default gateway setting to determine the hetwork identity.
In the 'crossover cable' configuration that has been posted, the Windows host can not contact the gateway and so determines, the network is 'unidentified. To fix the issue, try not setting a gateway at all. Or if that doesn't work, set the gateway as the address of the host at the other end of the cable.
E.g.
Windows host
IP 192.168.1.170
Mask 255.255.255.0
GW 192.168.1.177
Arduino Shield
IP 192.168.1.177
Mask 255.255.255.0
GW 192.168.1.170
MattS-UK:
Versions of Windows later than XP / Server 2003, utilise the default gateway setting to determine the hetwork identity.In the 'crossover cable' configuration that has been posted, the Windows host can not contact the gateway and so determines, the network is 'unidentified. To fix the issue, try not setting a gateway at all. Or if that doesn't work, set the gateway as the address of the host at the other end of the cable.
E.g.
Windows host
IP 192.168.1.170
Mask 255.255.255.0
GW 192.168.1.177Arduino Shield
IP 192.168.1.177
Mask 255.255.255.0
GW 192.168.1.170
Wow... the 2nd one works(no matter that it's still written unidentified network), but why... what's the idea ? can you explain me what i just did ?
crit1s:
Wow... the 2nd one works(no matter that it's still written unidentified network), but why... what's the idea ? can you explain me what i just did ?
How to put this?
Microsoft have made some interesting (as in odd) design choices when it comes to TCP/IP. 'Unidentified Network,' is one of those interesting choices. I haven't bothered to put a protocol sniffer on it yet, but I presume the Windows host is directing an arp request at the configured gateway address and when it does not get a reply from the gateway, it closes down the interface to deter 'man-in-the-middle' address spoofing. By setting the gateway to the far end of the wire, the source address in the arp reply matches that of the configured gateway.
You could also try changing the subnet mask at both ends to 255.255.255.255, which places both hosts on separate subnets, which causes all packets to be directed to their respective gateway address'. One more possibility, is to set the gatway to 127.0.0.1. These two options are possibly more 'correct'...But only if they work 
@MattS-UK: Thanks for that tidbit of knowledge. It confirms that my decision to abandon Windows in favor of Linux/Ubuntu was the correct one. I'll add that to my list of network questions when troubleshooting.
How's that even possible understanding all of the processes hm... i have such a lack of knowledge...
Thank you all for the help!
It isn't possible to know everything about computers. That is why these forums. I've been doing this a long time and, as you can see, I learn new stuff every day.