SWIP netblocks

[Danny McPherson]

I agree with Mike.  There are lots of ways that IP addresses 
can be allocated with non-contiguous masks.  For example, 
allocation mechanisms such as those defined in 
ftp://ftp.ietf.org/internet-drafts/draft-mcpherson-vlan-ipagg-01.txt, 
which could similarly be employed in DSL, cable, or lots of 
other environments.

-danny



> Ginny,
> 
> I'd say "no", and provide one example to support my position.
> 
> Many ISPs are deploying DSL services using bridged networking models.
> Typically, the ISP allocates a large block (/24 or so) at a time to an
> integrated routing and bridging interface, and then assigns customer
> addresses from this block one at a time as customers come online.  If a
> customer requires more than one IP address, these can be assigned, and they
> do not have to be assigned on CIDR boundaries at all.
> 
> If the assignment is larger than a /29, ARIN policy requires that the
> reassignment be documented via SWIP or RWhois.  Implementing this policy
> would force an ISP who needed to assign a customer (for example) 9 IP
> addresses for a bridged DSL service 16 addresses instead, a net waste of 7
> addresses.  This would be in conflict with one of ARIN's other stated policy
> goals, namely the conservation of IPv4 address space.
> 
> Peace,
> Mike Gogulski
> Chief Engineer
> DSL.net, Inc.
> 
> -----Original Message-----
> From: ginny listman [mailto:ginny at arin.net]
> Sent: Wednesday, January 03, 2001 11:10 AM
> To: dbwg at arin.net
> Subject: SWIP netblocks
> 
> 
> In reviewing what is currently stored in the database, there are a number
> of SWIPed netblocks that are not on the bit boundary.  For example,
> instead of SWIPing 0 to 255, an entire /24, 1 to 254 was SWIPed.  In the
> future, we will be operating in a cidr world, including displaying cidr
> blocks in whois.  For a block that is 1 to 254, the display will include 2
> /32, 2 /31, 2 /30, 2 /29, 2 /28, 2 /27, and 2 /26.  It would be a whole
> lot cleaner to display 1 /24.
> 
> How do people feel about enforcing allocations/assignments based on a
> single cidr block?  I could see an occasion where someone may want to
> assign 2-4 cidr blocks at a single time, but can we enforce, or strongly
> encouraging, a policy like this?  SWIP on the bit boundary.
> 
> Ginny