[ih] Why is TUBA assigned IP version 9

[Steve Deering]

On Sep 21, 2010, at 11:33 AM, John Kristoff wrote:

> Anyone know why TUBA was assigned IP version 9?

During the IPng process, I applied to IANA for an IP version number  
assignment for use in prototype implementations of SIP (Simple  
Internet Protocol), my proposal for IPng.  SIP was assigned number 6,  
because that was the next available value.  In order not to be seen as  
"blessing" SIP as the next version of IP,  Jon at the same time  
assigned IP version numbers to all the other IPng candidates then  
under consideration in the IETF, even though their headers didn't have  
or require an IP version number field.  Those assignments were as  
follows:

  6 - SIP
  7 - TP/IX
  8 - PIP
  9 - TUBA

SIP evolved/mutated into what was eventually adopted for IPng, and  
simply kept its version number.

Steve