Confederation with BGP Path selection

iBGP is running between routers in same sub-AS, eBGP is running between different sub-AS. However, when BGP calculate bset path, it doesn't treat them as real iBGP and eBGP

R4 received route to 200.200.200.8/29 which is in AS 200 from both AS100 eBGP router and iBGP router in sub AS64526. Path going through AS100 seems a shorter, but according to Cisco documentation, confederation AS_CONFED_SEQUENCE doesn't take account when BGP select best path.http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080094431.shtml

we can see R4 choose internal router R5 as the best path to 200.200.200.8/29

What the relationship between R2 and R4, they are both RR for redundancy. The IPExpert video configured them as RR-Client to each other, is this correct or doesn't matter? searched Internet seems most example they are just regular iBGP peers.

If they configured as RR-client to each other, when R4 received a route 200.200.200.32/28 from AS 100, it sent to R2, since R2 designated R4 as RR-Client, it advertised the route back to R4, R4 dropped it due to it.

--DENIED due to: ORIGINATOR is us; reflected from same cluster;

We see the confederation loop prevension mechanism took action here, for both CLUSTER_LIST and ORIGINATOR_ID check.

If they are configured as regualr iBGP, R4 received the route 200.200.200.32/28 from AS 100 router, then sent it ot R2. Since R2 received it from iBGP peer, acoording regular iBGP rule, it won't advertise to any other iBGP, only to RR-Client.

The result is same but regular iBGP make more sense.