Is there a method or tool(s) to prove network outages?

Warren Bailey wbailey at satelliteintelligencegroup.com
Mon Dec 2 03:09:13 UTC 2013


Keep in mind that inter web traffic has nothing to do with the overall
health of the radio link. In RF land, we really don¹t care what is going
over that link - just that we have enough RSL hitting the receiver to be
above threshold thus allowing the box to demodulate that signal. If your
radio is sitting at a threshold RSL of -108 and you¹re coming in at -105,
big trouble in little China (3dB fade murdered your link). Stop thinking
like a network engineer.. If your DS-1 was taking hits, an ICMP request
(or lack thereof) would mean little (read: zero) to me as an RF Engineer.
I want to see the BER/PER of the circuit over time so I can correlate
possible trouble with real world issues.

With that being said.. the tidal issue comes up a lot, and more times than
not I see someone who said ³Point that dish over there² and when it
magically works they have earned the title of ³Best RF Engineer in
History² until the tide rolls in and their link suddenly has ³issues². The
invention of cheap wireless has caused many people to believe they have in
depth wireless experience, and that is usually not the case.

Not trying to preach, but I¹ve spent a *TON* of time and other people¹s
money in multi path land.. If someone was responsible for the proper
design of the link multi path would not be a factor as it would be
addressed early on in the link. You are not going to gain much traction
with a wireless company when you call and tell them your pings aren¹t
working.. They are kind of like parents.. They just don¹t understand. ;)

//warren
Ps - I welcome any replies on or off list.. I know how frustrating it can
be to have a link that seems to work well until you look at it, so I
probably have a bit more compassion than others when talking about broken
Microwave/Satellite hops.

On 12/1/13, 5:40 PM, "Dobbins, Roland" <rdobbins at arbor.net> wrote:

>
>On Dec 2, 2013, at 6:26 AM, Warren Bailey
><wbailey at satelliteintelligencegroup.com> wrote:
>
>> I would hold off on considering Multipath as a problem until you see
>>the RSL. 
>
>Concur. It could also be related to precipitation or other adverse
>conditions.
>
>Or, in fact, it could be related to the 'UTM' box and/or something else
>on the endpoint network.  It could be a periodic DDoS attack, or traffic
>causing an availability hit as an unintended consequence.
>
>It's difficult to say without data.  Since the OP has the ability to
>gather IP-level data on his own network, he should utilize whatever
>instrumentation and telemetry he can set up in order to diagnose the
>issue as accurately as possible.
>
>And the OP should dig out his SLA and see what it says about the
>obligations of his upstream.
>
>-----------------------------------------------------------------------
>Roland Dobbins <rdobbins at arbor.net> // <http://www.arbornetworks.com>
>
>	  Luck is the residue of opportunity and design.
>
>		       -- John Milton
>
>




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