Hi Andrew!

Good Day!

Here's our situation.

We have four(4) upstream providers and we are doing BGP to each of them.
Right now, I have a netflow collector running flow-capture, flow-scan, and 
CUFlow.
On my CUFlow.cf, I have specified the AS numbers of those four upstream 
providers so that in 
CUGrapher.pl, I can highlight those four AS in the dropdown and then generate 
in/out graphical representation
of traffic going in and out of our network via those four AS. Next I have 
configure all ouf our routers to export version 5 peer-as
to our collector. Have I done the right steps here?

Next, I want to also graph the traffic going in and out of a particular AS we 
are interested in. If I include these AS numbers in my CUFlow.cf, I am guessing 
that the CUGrapher.pl will not produce any graphs for these AS numbers because 
the routers are exporting in peer-as instead of origin-as. Is my assumption 
here, correct? And as someone suggested, I will have to use CampusIO's 
extension to achieve both?

The explanation for peer-as and origin-as below from cisco is a little bit 
confusing or lack of further explanation as to what is this term "export 
statistics". All I know is that, I have netflows that looks like this, as seen 
in flowdumper:

FLOW
  index:          0xc7ffff
  router:         zzzz
  src IP:         x.x.x.x
  dst IP:         yyyy
  input ifIndex:  1
  output ifIndex: 27
  src port:       53
  dst port:       1036
  pkts:           1
  bytes:          367
  IP nexthop:     0.0.0.0
  start time:     Mon Jan 29 23:59:45 2007
  end time:       Mon Jan 29 23:59:45 2007
  protocol:       17
  tos:            0x0
  src AS:         1234
  dst AS:         5678
  src masklen:    24
  dst masklen:    24
  TCP flags:      0x0
  engine type:    0
  engine id:      0

And if I specify "peer-as" in my router ip flow-export configuration, the "src 
AS" will always be either one of those of our peer upstream providers where the 
ingress traffic passed by before it was seen by our routers, and the "dst AS" 
will always be the absolute destination AS.
But what if the traffic originated from our own AS, meaning egress traffic. 
Will the "src AS" be our own AS number or still either of those upstream 
providers?

Next, if I tell my routers to export using "origin-as", the "src AS" in my 
"FLOW" like that above, will always be the absolute source AS where the traffic 
came from, and the destination AS is unchanged as well (absolute).


Lastly, can someone here suggest a way to know who is consuming the traffic we 
are seeing in our MRTG graphs?
For example, our upstream provider A, at around 1:00 pm has reached 30M in MRTG 
scale. Given that the data source for this graph is the serial interface of our 
router facing the upstream provider A, how should I go about it using one of 
the flow-tools? Should I flow-cat the 12:00-1:00 pm flows and then flow-stat 
them or something? Did you have such goal like this before? 

Thanks.

I hope that this will be clarified so that the next time a new flow-tools user 
searches the archive using "origin-as, peer-as" as keywords, he or she will 
retrieve something useful.


----- Original Message ----
From: Andrew Mabe <[EMAIL PROTECTED]>
To: jay alvarez <[EMAIL PROTECTED]>
Sent: Wednesday, January 31, 2007 12:31:25 AM
Subject: Re: [Flow-tools] origin-AS vs peer-AS(RE:  In my case, should I choose 
peer-as or origin-as??)

 From Cisco PDF:

(Required) Enables the export of information in NetFlow cache entries.

•The version 9 keyword specifies that the export packet uses the  
Version 9 format.

•The origin-as keyword specifies that export statistics include the  
origin autonomous system (AS) for the source and destination.

•The peer-as keyword specifies that export statistics include the  
peer AS for the source and destination.

•The bgp-nexthop keyword specifies that export statistics include BGP  
next hop related information.

This command enables the export of origin AS information as well as  
BGP next hop information from the NetFlow main cache.

BTW: I use peer-as to graph my customers to/from my 9 ISP links.

On Jan 29, 2007, at 9:45 PM, jay alvarez wrote:

>
>
> ----- Original Message ----
> From: jay alvarez <[EMAIL PROTECTED]>
> To: Mark Prior <[EMAIL PROTECTED]>
> Cc: flow tools <[email protected]>
> Sent: Monday, January 29, 2007 4:05:22 PM
> Subject: origin-AS vs peer-AS(RE:  In my case, should I choose peer- 
> as or origin-as??)
>
>
>
> ----- Original Message ----
> From: Mark Prior <[EMAIL PROTECTED]>
> To: jay alvarez <[EMAIL PROTECTED]>
> Cc: flow tools <[email protected]>
> Sent: Wednesday, January 24, 2007 10:26:18 PM
> Subject: Re: [Flow-tools] In my case, should I choose peer-as or  
> origin-as??
>
> jay alvarez wrote:
>
>>> I'm only worried because I might be displaying erroneous reports,  
>>> let's say I use flow-stat to report the top > > destination or  
>>> source AS.
>
>> In that case you probably want origin-as.
>
>> Which version you choose depends on what data you want to mine and if
>> you want to know about the ultimate source or destination of the  
>> traffic
>> then you want origin-as. If you want to discover more about which
>> upstream is sending you the traffic then you want peer-as.
>
> So if I choose origin-AS then I will be able to create reports for  
> top absolute destination AS and top absolute source AS, as well as  
> graphs (CUGrapher.pl) because each netflow record will contain  
> absolute source and destination ASNs, but if I specify peer-as, I  
> can only generate top absolute destination AS reports but the top  
> source ASN which will be recorded in its netflow record will always  
> be either of those four peer AS/upstream providers where that  
> particular traffic have passed through before it reaches our  
> routers. Can anyone clear this for me.. And lastly, someone have  
> suggested using experimental CampusIO extensions which can generate  
> reports for both origin and peer as, I'll see if it fits our needs.
>
> Thanks...
>
>
>
> Mark.
>
>
>
>
>
>
>
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