154
C
HAPTER
4: C
ONFIGURING
P
ATH
B
UILDER
S330/S310 M
ODULES
, P
ORTS
,
AND
A
PPLICATIONS
FECN to EFCI Mapping
—Defines the mapping of FECN incoming on Frame Relay
to the outgoing ATM cell PTI congestion indicator.
Direct
—Mode 1 mapping; matches FECN to the PTI CN bit. When the serial
port is in this mode, it does not translate between Frame Relay (NLPID)
encapsulation, rather it sends it straight through the ATM network, possibly
onto a Frame Relay network or device.
Always 0
—Mode 2 mapping. This option sets the EFCI field to ‘congestion not
experienced.’ Mode 2 is an operational method for indicating data congestion
to either the ATM or Frame Relay network. Mode 2 allows for translation
between NLPID and LLC-SNAP encapsulation. It is used when connecting a
Frame Relay device or network to a non-Frame Relay device or network. For
example, if the PathBuilder S330 is connecting a router/FRAD over an ATM
network (public or private) and at the other site a router with an ATM
OC3/STM-1 UNI is connected to the WAN network, typically the router
OC3/STM-1 UNI does not support NLPID and requires mode 2 mapping so that
the packet can be encapsulated to LLC-SNAP.
DXI Virtual Circuit Parameters
If the serial port is configured as a DXI port,
you must set the following virtual circuit parameters in addition to the common
Shaper Number
,
Priority
, and
Early Packet Discard
parameters:
(DFA) VPI
—The virtual path indicator (VPI) number corresponding to the DFA
field:
0...15
. This parameter defines the selected VPI for Mapping to/from the Port
card (Router) to the trunk.
(DFA) VCI
—The virtual channel indicator (VCI) number corresponding to the DFA
field:
0...63
. This parameter defines the selected VPI for Mapping to/from the Port
card (Router) to the trunk.
(DFA) VCI Range
—The DXI virtual channel indicator range:
1...32
. This parameter
defines the range of VCs starting from the one selected, in twos. and allows quick
input of multiple VCs.
SDLC Virtual Circuit Parameters
If the serial port is configured as a SDLC port,
you simply set the common
Shaper Number
,
Priority
, and
Early Packet Discard
parameters.
Ethernet Port Virtual Circuit Parameters
For Ethernet port virtual circuits you simply set the common
Shaper Number
,
Priority
, and
Early Packet Discard
parameters.
CBR Module Virtual Circuit Parameters
The parameters that appear on the Add Virtual Circuit screen when you select the
CBR module to be a side of a circuit vary, depending on whether you select the
V.35 port or one of the T1/E1 ports. In addition to the common
Shaper Number
,
Priority
, and
Early Packet Discard
parameters, you must set the following
parameters:
Port
—The CBR module port number.