Implementation of RIPE-181++

  >> Jessica Yu <jyy at merit.edu> writes:
  >> >It should also be noted there is no direct relationship between  the
  >> >cost used in as-in and the preference used in interas-in.
  >> 
  >> Actually, the cost in as-in and the preference in interas-in need to be
  >> comparable.  

>No.

	Well, they are not competely unrelated.  See below. 

  >> aut-num: AS1
  >> as-in: from AS100 1 accept AS100        
  >> interas-in: from AS100 L1 R1 (pref=1) accept {a,b,c}
  >> interas-in: from AS100 L1 R1 (pref=2) accept {x,y,z}
  >> interas-in: from AS100 L2 R2 (pref=1) accept {x,y,z} 
  >> interas-in: from AS100 L2 R2 (pref=2) accept {a,b,c}
  >> 
  >> If people do explicitly list their interas-in policy, then there is no
  >> problem.  However, if people do not explicitly list them as the current
  >> version allows, then we will have a problem if the cost and pref is not
  >> comparable. 
  >>  
  >> aut-num: AS1
  >> as-in: from AS100 1 accept AS100
  >> interas-in: from AS100 L1 R1 (pref=1) accept {a,b,c}
  >> interas-in: from AS100 L2 R2 (pref=1) accept {x,y,z}
  >> 
  >> This implies that
  >> 
  >> interas-in: from AS100 L1 R1 (pref=1) accept {x,y,z}
  >> interas-in: from AS100 L2 R2 (pref=1) accept {a,b,c}

>It does not imply that. 
>According to the wording it implies:

>interas-in: from AS100 L1 R1 (pref=some) accept AS100
>interas-in: from AS100 L2 R2 (pref=some) accept AS100

>Where "some" is not explicitly defined by the text but implicitly
>greater than all preferences mentioned in interas-in attributes.

	What happen if I define my policy like

	interas-in: from AS100 L1 R1 (pref=2) accept {x,y,z}
        interas-in: from AS100 L2 R2 (pref=2) accept {a,b,c}

	then your scheme does not work because this really needs
	a preference which is smaller than the ones mentioned in interas-in
	attributes. 

	But even take what you said in consideration.  This "some" has to be 
	the one that does not equal and greater than the one specified in 
	'pref', in this case is 1.  When we have such requirement, that 
	really means the two are not completely uncomparable or no direct 
	relashionship at all.   

  >> This is incorrect policy.

>This is what was intended.

  >> So for this example, either we advice people the be carefully put their
  >> cost and pref that means they are not uncomparable, or have to have them
  >> explicitly list the interas policy which needs a change to the current
  >> text.

>For this example I would indeed advise people to say things explicitly.

>The implicit rules are intended for cases specifying exceptions like

>aut-num: AS1
>as-in: from AS100 1 accept AS1 AS2 AS3 AS4 AS5 AS6 AS7 
>as-in: from AS100 1 accept AS31 AS32 AS33 AS34 AS35 AS36 AS37 
>as-in: from AS100 1 accept AS61 AS62 AS63 AS64 AS65 AS66 AS67 
>interas-in: from AS100 L1 R1 (pref=1) accept AS34

>In such cases repeating all the AS numbers just adds noise, whereas the
>short form makes it immediatly obvious what the local policy deviation
>is.  Note that in practise this will often be true for your example case
>as well. 

					--Jessica



-------- Logged at  Wed Oct 5 18:46:00 MET 1994  ---------