Re: prevent transit AS

[edit policy-options]
as-path AS1 "1 .*";
policy-statement block_as1 {
    term as1 {
        from {
            protocol bgp;
            as-path AS1;
        }
        then reject;
    }
}

[edit protocols bgp group as3]
type external;
peer-as 3;
export block_as1;