Private use of non-RFC1918 IP space
skeeve at skeeve.org
Wed Feb 4 00:57:36 UTC 2009
Following myself up, and referencing a link someone else gave me in regards
Has the entry:
Private use of other reserved addresses
Several other address ranges, in addition to the official private ranges,
are reserved for other or future uses, including 126.96.36.199/8 and 188.8.131.52/8.
In recent years, large companies have begun to use this address space
internally. Though discouraged, it appears to have become an accepted
practice among larger companies to use these reserved address spaces when
connecting two private networks, to eliminate the chance of address
conflicts when using standards-based private ranges.
Now I'm not using this as justification.... just interesting to see people
have put it up there, and comment that a lot of large companies are using
1/8 and 2/8 for private networking.
From: Skeeve Stevens [mailto:skeeve at skeeve.org]
Sent: Wednesday, 4 February 2009 9:48 AM
To: 'David Conrad'; 'Bruce Grobler'
Cc: 'NANOG list'
Subject: RE: Private use of non-RFC1918 IP space
OK, I will make an (what looks to this list) embarrassing admission.
We use 184.108.40.206/8 for our internal ranges, but this is on a small scale.
We do it because of the kind of business we do... we manage many other much
larger networks which already use every possible overlapping RFC1918 network
you can imagine... we have half a dozen networks using 192.168.0, and even
more using many varied masks in the 10.0.0.0/8. We already have issues with
the overlapping networks as is, without making it worse for us by using on
I chose to go the 220.127.116.11 path because:
- It wont conflict with my customers and us doing our business
- As long as it is not APNIC who gets it, the chances of it conflicting will
be extremely minimal (rolls dice)
- We don't design customer networks with non-RFC1918 ranges unless there is
some extreme reason
- Yes it is potentially allocate-able in the future, but if it happens I
will deal with it then - just renumber or see the next point
- We will be fully IPv6 within 6-9 months with a separate VLAN which will
support legacy equipment with NAT-PT... this will still be an issue
interconnecting to customer networks, but we will think of something.
From: David Conrad [mailto:drc at virtualized.org]
Sent: Tuesday, 3 February 2009 6:48 AM
To: Bruce Grobler
Cc: NANOG list
Subject: Re: Private use of non-RFC1918 IP space
On Feb 2, 2009, at 8:10 AM, Bruce Grobler wrote:
> Most ISP's, if not all, null route 18.104.22.168/8 therefore you shouldn't
> encounter any problems using it in a private network.
Is this true?
This will cause endless entertainment when IANA allocates 22.214.171.124/8
sometime within the next two or three years...
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