[Sis-csi] CANDOS networking details

[Ivancic, William D. (GRC-RCN0)]

Keith,

Two important things to point out with regards to CANDOS are independent
of mobile-ip (which worked quite well I might add).

#1.  Using static (predictive) routing, CANDOS was able to do blind
commanding (sending commands over a unidirectional link such as may be
required in an emergency situation or to hard reboot a system); and

#2.  Static routing does exactly what you tell it to do.  Static routes
tend to default to the highest priority route (although this is
configurable in Cisco routers and probably other systems).  Thus, when
CANDOS did not remove the static route, the data when exactly where it
was told to go... Off into the either.

Will

******************************
William D. Ivancic
Phone 216-433-3494
Fax 216-433-8705
Lab 216-433-2620
Mobile 440-503-4892
http://roland.grc.nasa.gov/~ivancic 
 

> -----Original Message-----
> From: sis-csi-bounces at mailman.ccsds.org 
> [mailto:sis-csi-bounces at mailman.ccsds.org] On Behalf Of Keith Hogie
> Sent: Tuesday, February 06, 2007 3:22 PM
> Cc: sis-csi at mailman.ccsds.org
> Subject: [Sis-csi] CANDOS networking details
> 
> All,
> 
>    Attached is some more details on the CANDOS configuration. 
>  It has Dave's high level diagram followed by more details on 
> the I&T systems, the operational systems, and external 
> systems.  I also added some words on basic data flow 
> characteristics and Mobile IP and manual tunnel operations.
> 
>    The IP addresses on one of the diagrams are not real but 
> are representative of those used.  The main thing to keep in 
> mind is that the spacecraft IP address came from the control 
> center subnet address range which was a 32 address subnet.  
> There were lots of other subnets on the way to the spacecraft 
> but IP tunneling made them transparent to forward traffic.
> 
>    See if any of this makes sense and I can try to fill in 
> details if you have questions.  It has been 4 years since we 
> did this and I don' remember all the details but I did find 
> our log book and we have lots of configuration, log files, 
> and data files around if we have detailed questions.
> 
> ----------------------------------------------------------------------
>    Keith Hogie                   e-mail: Keith.Hogie at gsfc.nasa.gov
>    Computer Sciences Corp.       office: 301-794-2999  fax: 
> 301-794-9480
>    7700 Hubble Dr.
>    Lanham-Seabrook, MD 20706  USA        301-286-3203 @ NASA/Goddard
> ----------------------------------------------------------------------
> 
>