Route Policy

Route policy is the shared control-plane filter and rewrite surface used by BGP, redistribution, and import analysis. It gives protocol docs one consistent way to describe filtering and attribute changes.

Support level

Area	Level	Notes
Prefix lists	Supported	IPv4 prefix matching with ge/le where implemented.
Route maps	Supported	Ordered permit/deny sequences with match/set actions.
AS-path ACLs	Supported	Regex-like matching for BGP AS_PATH strings.
Community lists	Supported	Standard exact and expanded regex-style community matching.
Redistribution filters	Supported	Used by BGP and OSPF-related import paths.

Standards coverage

Standard	Coverage	Notes
RFC 4271 policy attributes	Behaviour model	LOCAL_PREF, MED, AS_PATH, NEXT_HOP, ORIGIN.
RFC 1997 communities	Supported	Standard community representation and matching.
Cisco route-map semantics	Behaviour model	Ordered sequence evaluation.

Feature matrix

Feature	Status	Notes
ip prefix-list	Supported	Prefix filters.
route-map NAME permit/deny <seq>	Supported	Ordered policy.
match ip address prefix-list	Supported	Prefix-list match.
match as-path	Supported	AS_PATH ACL match.
match community	Supported	Community-list match.
set local-preference	Supported	BGP attribute rewrite.
set metric	Supported	MED or protocol metric depending on context.
set as-path prepend	Supported	Outbound BGP path prepending.
set community	Supported	Replace/add/remove community values.

Vendor command matrix

Command	IOS-style	Junos-style	VyOS-style	Notes
ip prefix-list PL permit 10.0.0.0/8 le 24	Supported	Partial	Supported	Prefix filter.
route-map RM permit 10	Supported	Partial	Supported	Policy sequence.
ip as-path access-list 10 permit _65001_	Supported	n/a	Partial	AS_PATH match.
ip community-list standard C permit 65000:10	Supported	Partial	Partial	Community match.
show route-map	Supported	Partial	Partial	Policy view.

Behaviour notes

Route maps are evaluated in sequence order. A route that does not match any permit sequence is rejected in policy contexts that require an explicit permit.

Examples

Canonical example

configure terminal
ip prefix-list CUSTOMER permit 10.10.0.0/16 le 24
route-map CUSTOMER-IN permit 10
 match ip address prefix-list CUSTOMER
 set local-preference 200
router bgp 65000
 neighbor 192.0.2.2 route-map CUSTOMER-IN in
end

Vendor styles

IOS-style

ip prefix-list CUSTOMER permit 10.10.0.0/16 le 24
route-map CUSTOMER-IN permit 10
 match ip address prefix-list CUSTOMER
 set local-preference 200

Junos-style

set policy-options prefix-list CUSTOMER 10.10.0.0/16
set policy-options policy-statement CUSTOMER-IN term 10 from prefix-list CUSTOMER
set policy-options policy-statement CUSTOMER-IN term 10 then local-preference 200
set policy-options policy-statement CUSTOMER-IN term 10 then accept

VyOS-style

set policy prefix-list CUSTOMER rule 10 action permit
set policy prefix-list CUSTOMER rule 10 prefix 10.10.0.0/16
set policy route-map CUSTOMER-IN rule 10 action permit
set policy route-map CUSTOMER-IN rule 10 set local-preference 200

Known limits

Junos policy-statement parity, Cisco AS-path regex boundary syntax fidelity, large-community support, RPKI validation, and complex policy language features are not complete.