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[LDM #BQD-554715]: ldm restart

Carol,

> What is a NAT device? What would be an example of this?

NAT stands for "Network Address Translation". NAT devices rewrite the source
IPv4 address in outgoing packets from a private network IPv4 address
(typically starting with 192 or 10) to the public IPv4 address of the NAT
device. They also keep track of connections so that the destination address
of an incoming IPv4 packet (which will be that of the NAT device) can be
rewritten to that of the (otherwise) hidden host to which it should go. One
of the reasons that NAT devices were developed was to workaround the looming
exhaustion of the IPv4 address namespace, which only has 32 bits.

If the connection from the LDM on amrc.ssec.wisc.edu to Herbie goes through
a NAT device, then there's a risk that another LDM on another computer in
the ssec.wisc.edu domain will make the same or overlapping REQUEST to Herbie
via the same NAT device. In this case, the LDM on Herbie will see the same or
overlapping REQUESTs *from the same downstream host* (the NAT device), in
which case it will deny or reduce one of the requests so as not to abuse
bandwidth for no good reason.

More information on NAT devices can be found at
<https://en.wikipedia.org/wiki/Network_address_translation>.

So, from Herbie's perspective, is amrc.ssec.wisc.edu behind a NAT device
and, if so, could another LDM running on a computer behind the same NAT
device also be requesting from Herbie?

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: BQD-554715
Department: Support LDM
Priority: Normal
Status: Closed
===================
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