Suchitra, If you're configuring NAT on a Cisco router, it will take care of most of the ARP related stuff for you. Just to recap: ARP (Address Resolution Protocol or whatever) is used to translate IP addresses into Ethernet addresses. It's really only of interest once the stuff gets to the LAN and needs to get ferried to the right ethernet card. It's "layer 2" stuff, yeah? NAT is a concept whose basic idea is the translate IP addreses into other IP addresses. People use NAT for a variety of devious reasons, but basically it was an idea to conserve IP address space. NAT is "layer 3" stuff. The only reason you need to know about ARP in relation to NAT is to make sure that the device performing NAT knows that it needs to reply to ARP requests for any of the NAT translations it is currently maintaining. IMO, any device that doesn't do this automatically is kind of broken, so you shouldn't need to think too hard about it. Specifically, if you're getting a Cisco to do NAT, you don't need to enter any of the arp commands, unless you're doing something "interesting". Go plumb the inky depths of cisco.com - there is loads of info there. > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] > Sent: Thursday, 7 October 1999 1:57 PM > To: [EMAIL PROTECTED] > Cc: [EMAIL PROTECTED]; [EMAIL PROTECTED] > Subject: Re: ARP > > > When using NAT , arp is used to accept packets for the > translated IP > address since there is no node replying to ARP requests for the > translated IP - mac address. [Lots of stuff snipped] > > > Hope this helps Good workaround if you have a box that has a broken NAT implementation.. > and I have not confused the issue. Welllll....maybe a little. > > Marcus > > > ______________________________ Reply Separator > _________________________________ > Subject: Re: ARP > Author: lists ([EMAIL PROTECTED]) at unix,mime > Date: 07/10/99 12:12 > > > On Tue, Oct 05, 1999 at 10:43:02AM +0530, suchi wrote: > > As i am new to the concept of NAT please could someone help me out. > > Please could someone tell me what is the function of ARP > while doing NAT. > > I would also be very thankful if I was pointed to some good > Docs on NAT and co > nfiguring the same on cisco routers. > > -- Ben Nagy Network Consultant, CPM&S Group of Companies PGP Key ID: 0x1A86E304 Mobile: +61 414 411 520 - [To unsubscribe, send mail to [EMAIL PROTECTED] with "unsubscribe firewalls" in the body of the message.]
