FBT-ORNT-11-B

[czql5v]

Hi All,

This is my first post on this forum and I wondered whether someone could off some advice.

I have inherited what appears to be an undocumented Network and I am attempting to carry out an analysis of what exactly we have and how everything fits together. 

I particularly need to know about our FBT-ORNT-11-B X7 devices which appear to be Data Leased Lines. I can account for 2 of theses devices and know they are leased lines from a local company. The local company claim that we do not use their Leased line as our internet connection. That is backed up by the fact that a "whats' my ip address" appears to be different to what they claim to have leased us. Is there a way to tell that we are definitely not using their leased line for internet purposes by chasing the ethernet cable from the 3501 cisco router to a switch port and checking the config on the port? What should I be looking out for in the config?

Does anyone know if there is any way I can trace who owns these devices. I have received invoices from various companies who we rent leased lines from. I am attempting to find out which of these companies actually provide us with internet access. If I trace the links from the FBT - 3501 Cisco Router to a switch and then interrogate the switch ports what would tell me that we are using that particular FBT leased line for our Internet?

Any help or advice on the above would be gratefully received.

Regards.

[pieterh]

if you use leased lines an those are not for internet connection, then they are possibly connecting to a branch office
the company should be able to give you information on what address (city/street) those lines are leading from/to
from this information you could associate them to a remote location of your company

[czql5v]

Hi Pieterh,
Thanks for the information.
Is there any way I could possibly tell if they are used for internet connection or not?
Would I also be able to tell what the connections are just by chasing the cat5 cables to their switch port destination and looking for the port configuration of the switch?
Thanks for the reply its very much appreciated.
Regards.

[pieterh · Accepted solution]

yes, drawing schematics of the physical connections between your equipment (layer-2) is phase-1
phase-2 is collecting your switches/routers configuration, specifically to the leased lines
and determine what ip-adresses and ip-subnets are used to connect to those leased lines
with this information you can determine how ip-adresses are routed (layer-3) and what device is used for the internet connection

you may also be able to traceback the ip-addresses found in "whatismyip" in the public whois database
IP WHOIS Lookup - Lookup IP WHOIS Information - WhatIsMyIP.com®
this will display to what company an ip-address (or range of addresses) is registered
NB! this company need not be the company of your contract,
it could be they delegate registration of a subrange to an intermediate company, 
this registration may be on your company then name, the company name that provides your internet access or an intermediate
but this will give you a start for a company to query

[czql5v]

Hi Pieterh,

Thank you very much for the information it has helped me understand a little more about the infra.

Regards.