RE: Different Internet service providers

["Andy Cuff (Talisker)" <SecurityLists () securitywizardry com>]

Hi Francisco,
We made the mistake of using the same ISP for both our links and are still
suffering as a result.  The cost saving was short lived and whilst up time
was largely maintained we suffered from:

Internal ISP routing problems, home workers couldn't access our primary
network when connecting from the same ISP. This wouldn't have happened with
diverse ISP
Spam Black Lists, all the ISP IP addresses appeared on spam black lists.
Had we had another ISP we would have just changed the mx records
No reverse DNS, our old expensive ISP allowed this
The 24x7 manned support turned out to be, a human being raising a ticket for
the next day

Also consider outages, DDOS and as we once had IP hijack

Regards

Andy Cuff
Computer Network Defence Ltd
www.networkintrusion.co.uk

Skype: Taliskeruk
LinkedIN http://www.linkedin.com/in/andycuff 

> -----Original Message-----
> From: listbounce () securityfocus com 
> [mailto:listbounce () securityfocus com] On Behalf Of Francisco 
> Neira Basso
> Sent: Tuesday, August 12, 2008 4:46 PM
> To: security-basics () securityfocus com
> Subject: Different Internet service providers
>
> Hi all,
>
> I am trying to defend my point about the following:
> To have real redundancy with our Internet access it is 
> necessary to have
> 2 different ISPs.
>
> At the moment, we have two providers, one with a fiberoptic 
> last mile and the other with microwave link. Obviously they 
> also have different networks and points of presence.
>
> One of the providers is arguing and willing to sell us _both_ 
> accesses and I want to backup my point with additional arguments.
>
> Is there a written standard such as 17799 or 27001 that 
> recommends different ISPs in order to enhance the business continuity?
>
> Thanks in advance for yuor replies and comments.
>
> Regards,
>
>
>
> --
> Francisco Neira B.
> Seguridad de la Informacion
> Defensoria del Pueblo
> Lima, Peru  -05:00 UTC