Traffic Management for the Available Bit Rate (ABR) Service in ...

BN=1, and shall set the direction to backward. The destination shall assign
values to the various RM-cell elds as speci ed for destination generated cells
in Table 5-4.
6. When a forward RM-cell with CLP=1 is turned around it may be sent in-rate
(with CLP=0) or out-of-rate (with CLP=1)
Notes-
1. \Turn around" designates a destination process of transmitting a backward
RM-cell in response to having received a forward RM-cell.
2. It is recommended to turn around as many RM-cells as possible to minimize
turn-around delay, rst by using in-rate opportunities and then by using out-
of-rate opportunities as available. Issues regarding turning RM-cells around are
discussed in Appendix I.7.
5.10.6 Switch Behavior
The following items de ne the switch behavior for CLP=0 and CLP=1 cell streams
of a connection. By convention, the CLP=0 stream is referred to as in-rate, and the
CLP=1 stream is referred to as out-of-rate. Data cells shall not be sent with CLP=1.
1. A switch shall implement atleast one of the following methods to control con-
gestion at queueing points:
a) EFCI marking: The switch may set the EFCI state in the data cell headers�
b) Relative Rate Marking: The switchmay set CI=1 or NI=1 in forward and/or
backward RM-cells� item[c)] Explicit Rate Marking: The switchmay reduce
the ER eld of forward and/or backward RM-cells (Explicit Rate Marking)�
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