Alcatel-Lucent 7710 SR SONET, Руководство по настройке

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Interface Configuration
7710 SR OS Interface Configuration Guide Page 267
crc
Syntax crc { 16 | 32 }
Context config>port>sonet-sdh>path
Description
A 16 bit CRC can only be configured on an OC-3 channel, all other channel speeds must use a 32 bit CRC
except for the paths configured with encap-type atm at OC3 speed.
Default
16 for OC-3, DS-1, DS-3
32 for OC-12, OC-48, ATM-OC12/3, etc.
Note: The CRC default is 32 when the encap-type is set to ATM and also, the default cannot be changed
when the encap-type is set to ATM.
Parameters 16 — Use 16 bit checksum for the associated port/channel.
32 — Use 32 bit checksum for the associated port/channel.
encap-type
Syntax encap-type { atm | bcp-null | bcp-dot1q | ipcp | ppp-auto | frame-relay | wan-mirror | cisco-
hdlc }
Context config>port>sonet-sdh>path
Description This command configures the encapsulation method used to distinguish customer traffic on an access
SONET/SDH channel sub-port.
When the encap-type is set to ATM the CRC default cannot be changed.
When the encap-type is ATM, ATM sub-layer verification (GR-1248-CORE, Generic Requirements for
Operations of ATM Network Elements (NEs) ) is automatically enabled. The result of the verification
includes:
• Out of Cell Delineation (OCD) event count. The OCD event count is described in RFC 2515, Defini-
tions of Managed Objects for ATM Management . Note that multiple events occurring within a second
will be counted as 1 event for ATM and ASAP MDAs as a result of a hardware limit.
• Loss of Cell Delineation defect/alarm. The LCD defect/alarm is defined in RFC 2515, Definitions of
Managed Objects for ATM Management . When a path is in an LCD defect state, the path’s operational
status will be down. When a path exits the LCD state, the path’s operational status will change to up
(assuming nothing else causes the path to stay down). A trap is raised to indicate the LCD status change.
Also a P-RDI is sent to indicate the defect to the remote end.
The encap-type is only required when configuring a SONET/SDH path for access mode.
The no form of this command restores the default.
Default bcp-null
Parameters atm — Specifies that the encapsulation on the port is ATM.
bcp-null — Only a single service is configured on this channel and IEEE 802.1Q tags are not used as a
service delimiter. Any IEEE 802.1Q tags encountered are regarded as part of the customer payload and