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Cisco ASR 1000 Series Aggregation Services Routers SIP and SPA Software Configuration Guide
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Chapter 6 Overview of the ATM SPAs
Supported Features
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Error counts for B3
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Threshold crossing alarms for B3 (B3-TCA)
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Loss of pointer (PLOP)
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New pointer events (NEWPTR)
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Positive stuffing event (PSE)
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Negative stuffing event (NSE)
• The following loopback tests are supported:
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Network (line) loopback
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Internal (diagnostic) loopback
• Supported SONET/SDH synchronization:
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Local (internal) timing (for inter-router connections over dark fiber or wavelength division
multiplexing [WDM] equipment)
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Loop (line) timing (for connecting to SONET/SDH equipment)
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+/– 4.6 ppm clock accuracy over full operating temperature
Layer 2 Features
• Supports the following encapsulation types:
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AAL5SNAP (LLC/SNAP)
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AAL5MUX (VC multiplexing)
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AAL5NLPID
• Supports the following ATM traffic classes and per-VC traffic shaping modes:
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Constant bit rate (CBR) with peak rate
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Unspecified bit rate (UBR) with peak cell rate (PCR)
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Non-real-time variable bit rate (VBR-nrt)
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Variable bit rate real-time (VBR-rt)
Note ATM shaping is supported, but class queue-based shaping is not.
• ATM multipoint connections (beginning in Cisco IOS XE Release 2.5)
• ATM point-to-point connections
• Explicit Forward Congestion Indication (EFCI) bit in the ATM cell header
• AToM VP and VC Mode Cell Relay support
• RFC 2225, Classical IP and ARP over ATM (obsoletes RFC 1577)
Layer 3 Features
• ATM over MPLS (AToM) in AAL0 VC and VP mode