Re: [ns] Disable ARP

[Pedro Vale Estrela]

I've got the same problem, and using this code does not solve the problem
for all cases (in my particular simulation)

Instead, I'm using this with great success:

In C++, at the top of  ARPTable::arpresolve , insert this code that requires
#include "utils_ns.h" (see
http://tagus.inesc-id.pt/~pestrela/ns2/contributed_code.html#_Toc147652229)

--- cut here ---

TCL_EVALFr("ARP_find_mobile_iaddr2mac %d", dst);
LL *ll = (LL *)TclObject::lookup(Tcl::instance().result());

if(!ll){
        dprintf("Error: LL empty\n");   
        exit(-1);
}
                        
int mac = ll->mac_->addr();
mac_->hdr_dst((char*) HDR_MAC(p), mac);
return 0;

--- cut here ---


then, add this tcl code to your script or /tcl/lib/ns-lib.tcl. I'm not sure,
but this code MIGHT require the NOAH extension because that 
for {set i 0} { $i < [Node set nn_] loop.


--- cut here ---


# Given the node handle, return the haddr, iaddr or ID
proc NOAH_handle2iaddr { handle } {

        if { $handle == "-1" } {
                return "-1"
        }

        set iaddr [$handle address?]
        return $iaddr
}



#
# Given the node's address in haddr, iaddr or ID, search and return the
handle
# (TODO:) create an array at creation to store these pairs for faster lookup
#
proc NOAH_iaddr2handle { node_iaddr } {
        if { $node_iaddr == "-1" } {
                return "-1"
        }

        set ns_ [Simulator instance]

        for {set i 0} { $i < [Node set nn_]} {incr i} {
                set node_handle [$ns_ set Node_($i)]
                
                if {[string compare [NOAH_handle2iaddr $node_handle]
$node_iaddr] == 0} {
                        return $node_handle
                }
        }
        
        return "-1"
}


##
## PROC: returns the handle of a given NODE, by its iaddress
##

## FIXME: assume itf(0), codigo C++ devolve mac dessa interface
##
## this code is used by the disabled ARP (option 2)
proc ARP_find_mobile_iaddr2mac { iaddr } {
        set ns_ [Simulator instance]
        set MH_node_handle [NOAH_iaddr2handle $iaddr]

        set ll [$MH_node_handle set ll_(0)]

        #puts "found: $MH_node_handle $ll"
        return $ll
}

--- cut here ---






---------

Re: [ns] Disable ARP
Ahmad Khayyat
Wed, 28 Feb 2007 02:27:15 -0800

Never mind.
The two lines work perfectly. They just happened to trigger another
problem, which is taken care of now :)

On Tue, 27 Feb 2007 18:27:37 -0500
Ahmad Khayyat <[EMAIL PROTECTED]> wrote:

> What is the easiest way to disable the use of the ARP protocol?
> I guess the IP address corresponds to the MAC address in ns-2, doesn't
> it? So how do I make the LL/ARP modules use it immediately without
> using ARP?
> 
> I tried adding the following two lines at the top of
> ARPTable::arpresolve(nsaddr_t dst, Packet *p, LL *ll)
> 
> mac_->hdr_dst((char*) HDR_MAC(p), dst);
> return 0;
> 
> but that caused strange behaviour on rare occasions, where a packet
> suddenly would appear in another far node. Playing with ARP doesn't
> explain the problem for me, but somehow removing those two lines
> gets rid of the strange behaviour. So, what is a proper way of
> disabling ARP?
> 
> Thanks..
> Ahmad