BGP filter lists

 router bgp 65110
   neighbor 1.1.1.1 remote-as 65109
   neighbor 1.1.1.1 filter-list 1 in
 !
 ip as-path access-list 1 permit ^65109$
 !
 show ip bgp regexp _65110_

• Need to do a CLEAR IP BGP * to apply the filter-list.
• This will only allow routes from AS 65109.
• This is the shortest and simplest access-list.