Congestion Control
Page 29-12
Notification By FECN
Frame Relay headers also contain a congestion control bit called
FECN
(Forwards Explicit
Congestion Notification), which is usually pronounced “Feckon.” Like
BECN
, the
FECN
bit also
notifies a
WSX
or Bridge/Router of congestions problems. However, it is set by the Frame
Relay network in frames that are actually experiencing congestion. When the
WSX
receives
frames with their
FECN
bit set, it knows that congestion is already occurring on the virtual
circuit in the direction that these
FECN
frames are travelling. The
WSX
reacts by reducing the
data flow down to the
CIR
for data in the opposite direction. If the
FECNs
persist, then data
flow is stepped down even further. Data flow will gradually increase back up to the normal
rate as soon as
FECNs
or
BECNs
are no longer received.
Congestion Notification Using a FECN
Congestion. FECN flag
set in frames experi-
encing congestion.
Frame Relay Virtual Circuit
WSX or Bridge/Rout-
e r a t t h i s e n d
receives FECN and
can adjust traffic flow
down to the CIR, or
below, for outgoing
traffic in the opposite
direction.
Содержание Omni Switch/Router
Страница 1: ...Part No 060166 10 Rev C March 2005 Omni Switch Router User Manual Release 4 5 www alcatel com ...
Страница 4: ...page iv ...
Страница 110: ...WAN Modules Page 3 40 ...
Страница 156: ...UI Table Filtering Using Search and Filter Commands Page 4 46 ...
Страница 164: ...Using ZMODEM Page 5 8 ...
Страница 186: ...Displaying and Setting the Swap State Page 6 22 ...
Страница 202: ...Creating a New File System Page 7 16 ...
Страница 270: ...Displaying Secure Access Entries in the MPM Log Page 10 14 ...
Страница 430: ...OmniChannel Page 15 16 ...
Страница 496: ...Configuring Source Route to Transparent Bridging Page 17 48 ...
Страница 542: ...Dissimilar LAN Switching Capabilities Page 18 46 ...
Страница 646: ...Application Example DHCP Policies Page 20 30 ...
Страница 660: ...GMAP Page 21 14 ...
Страница 710: ...Viewing the Virtual Interface of Multicast VLANs Page 23 16 ...
Страница 722: ...Application Example 5 Page 24 12 ...
Страница 788: ...Viewing UDP Relay Statistics Page 26 24 ...
Страница 872: ...The WAN Port Software Menu Page 28 46 ...
Страница 960: ...Deleting a PPP Entity Page 30 22 ...
Страница 978: ...Displaying Link Status Page 31 18 ...
Страница 988: ...Displaying ISDN Configuration Entry Status Page 32 10 ...
Страница 1024: ...Backup Services Commands Page 34 14 ...
Страница 1062: ...Diagnostic Test Cable Schematics Page 36 24 ...
Страница 1072: ...Configuring a Switch with an MPX Page A 10 ...
Страница 1086: ...Page B 14 ...
Страница 1100: ...Page I 14 Index ...