[irrtoolset]generating import filters with RtConfig

Dear all,
I'm quite new to RtConfig, I would like to know how I can generate 
import filters both using prefix lists and as-path lists.

Playing around with RIPE test database I got this:
if I specify an import policy in such a way:

import: from ASx accept ASy

(having a route object for ASy),
then "@RtConfig import ASx <ip-addr-x> ASy <ip-addr-y>" gives me back a 
filter based on prefix lists.

Otherwise, if I specify an import policy (or similar):

import: from ASx accept <^ASy+$>

then I get back a filter based on an as-path.

So the main difference seems to reside in the way the aut-num object is 
written: using simple AS names gives prefix list filters, using regular 
expressions on AS names gives as-path based filters, am I right ?
Is there a way to combine both things to obtain both types of filters 
for the same peering relationship ?

Thank you in advance and best regards,
Francesco Ferreri


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Francesco Ferreri

NaMeX - Nautilus Mediterranean Exchange

Via dei Tizii 6b, 00185 - Roma
Tel. +39-0644486.302
E-mail: f.ferreri at namex.it
WWW http://www.namex.it
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