Two Ways of Frame Relay DE Set
DE bit set means Eligible for Discarding during periods of traffic congestion of frame relay network. It is congestion avoidance mechanism in FR. Obviously, DE bit set is for out-bound traffic of a router to FR switch. There are three ways to set DE bit.
1. FR DE List
Step 1: Classifier traffic by ACL
Step 2: Apply DE List
Step 3: Map DE List to DLCI
! Classifier
access-list 101 permit tcp any any eq www
! Mark
frame-relay de-list 1 protocol ip list 101
! Mapping
interface s0/0
frame-realy de-group 1 101
2. MQC
Step 1: Define Class-map
Step 2: Define Policy-map
Step 3: Apply to out-bound traffic
class-map WWW
match ip address 101
!
policy-map WWW_PO
class WWW
set fr-de
!
interface s0/0
service-policy output WWW_PO
!
access-list 101 permit tcp any any eq www
!
ip cef
3. FRTS
Step 1: Switch on Frame Relay Traffic Shapping on the interface level. Then, DE is set automatically.
interface s0/0
frame-relay traffic-shapping
