3Com 3C63100-AC-C - PathBuilder S600 Bridge/router Reference Manual page 179

Figure 138 FRF.8 Transparent Encapsulation Mode
DLCI
FRR
Translation—Used in cases when you have ATM devices that do not support
1490 as a protocol across their ATM trunks; for example, when you have an
PathBuilder S600 terminating the ATM network at one end and an ATM-ready
device, such as a router with an OC-3 UNI, at the other end. Typically these
ATM-ready devices do not support 1490 as a protocol across their ATM trunks, so
you have to do LLC_SNAP (1483) per FRF.8. Mode 1F does 1490 to 1483
translation. See Figure 139.
Figure 139 Translation Encapsulation Mode
DLCI
FRR
RFC 1490
DE to CLP Mapping—Frame Relay Discard Eligibility field to Cell Loss Priority field
mapping. This parameter defines the value to which CLP will be set in outgoing
ATM cells. The available settings depend on what interworking mode you have
selected: Network or Service.
The following settings are available for Network interworking mode:
Direct—Mode 1 mapping; matches DE value to CLP value. When the serial
port is in this mode, it does not translate between Frame Relay (NLPID)
encapsulation, rather it send it straight through the ATM network, possibly
onto a Frame Relay network or device.
None—No DE to CLP Mapping
VCC
ATM
RFC 1490 Encapsulated
VCC
ATM
Translation
Configuring Virtual Circuits
DLCI
FRR
ATM Router with FRR IWF
RFC 1483
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