BGP routes discrepancy

i have a small lab of 3 routers in dual-homed hub & spoke :R1, R2, R3. R1 is
the Hub. R2 & R3 are in the same AS, and R1 is acting as the ISP. each spoke
advertises 1 network (R2=172.16.32.x and R1=172.16.64.x), and the ISP (R1)
advertises 3 networks: 192.168.100.0., 1.1.1.0, and 11.11.11.0. R1 and R2
have an iBGP peering.

my questions is: how come R1 shows 5 prefixes being sent to R2 vs 3 sent to
R3? more over, both R2 and R3 show only 3 prefixes being learned from R1.
all seem to checkout on R3 (showing only 3 prefixes sent/received), but the
output on R2 puzzles me a bit. shouldn't it reflect 3 prefixes just like R3?
There are no filters whatsoever on any of the routers, and i have done a
hard reset a couple of times. please advise.
Thanks in advance for your input

pertinent config below:
===
R1: 192.168.100.1
===

R1-ISP#sho ip bgp neighbors 172.16.64.1 advertised-routes
BGP table version is 6, local router ID is 192.168.100.1
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network Next Hop Metric LocPrf Weight Path
*> 1.1.1.0/24 0.0.0.0 0 32768 i
*> 11.11.11.0/24 0.0.0.0 0 32768 i
*> 172.16.32.0/24 172.16.32.1 0 0 64512 i
*> 172.16.64.0/24 172.16.32.1 0 64512 i
*> 192.168.100.0 0.0.0.0 0 32768 i
*
Total number of prefixes 5*

!!!!
R1-ISP#sho ip bgp neighbors 172.16.32.1 advertised-routes
BGP table version is 6, local router ID is 192.168.100.1
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network Next Hop Metric LocPrf Weight Path
*> 1.1.1.0/24 0.0.0.0 0 32768 i
*> 11.11.11.0/24 0.0.0.0 0 32768 i
*> 192.168.100.0 0.0.0.0 0 32768 i

*Total number of prefixes 3*
!!!!
!!!!!!

R1-ISP#sho run | be router bgp
router bgp 200
 no synchronization
 bgp log-neighbor-changes
 network 1.1.1.0
 network 1.1.1.0 mask 255.255.255.0
 network 11.11.11.0
 network 11.11.11.0 mask 255.255.255.0
 network 192.168.100.0
 aggregate-address 2.2.2.0 255.255.255.0 as-set summary-only
 neighbor 172.16.32.1 remote-as 64512
 neighbor 172.16.32.1 ebgp-multihop 2
 neighbor 172.16.32.1 update-source Loopback0
 neighbor 172.16.64.1 remote-as 64512
 neighbor 172.16.64.1 ebgp-multihop 2
 neighbor 172.16.64.1 update-source Loopback0
 no auto-summary
!
===
R2: 172.16.64.1
===

R2-SanJose1#sho ip bgp neighbo 192.168.100.1 received-routes
BGP table version is 67, local router ID is 172.16.64.1
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network Next Hop Metric LocPrf Weight Path
*> 1.1.1.0/24 192.168.100.1 0 0 200 i
*> 11.11.11.0/24 192.168.100.1 0 0 200 i
*> 192.168.100.0 192.168.100.1 0 0 200 i

*Total number of prefixes 3*
R2-SanJose1#

===
R3: 172.16.32.1
===
R3-SanJose2#sho ip bgp neighbo 192.168.100.1 received-routes
BGP table version is 43, local router ID is 172.16.32.1
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network Next Hop Metric LocPrf Weight Path
*> 1.1.1.0/24 192.168.100.1 0 0 200 i
*> 11.11.11.0/24 192.168.100.1 0 0 200 i
*> 192.168.100.0 192.168.100.1 0 0 200 i

Total number of prefixes 3

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Received on Fri Jun 04 2010 - 07:28:25 ART