Cisco ASR 900 Series Release Notes

4
Cisco IOS XE 3S Release Notes for the Cisco ASR 903 Router
OL-26630-12
Chapter
Limitations and Restrictions
MLPPP Limitations
The following limitations apply when using MLPPP on the Cisco ASR 903 Router:
• All links in an MLPPP bundle must be on the same interface module.
• All links in an MLPPP bundle must be of the same bandwidth.
• The Cisco ASR 903 Router supports a maximum of 8 links per bundle
• To change the MLPPP bundle fragmentation mode between enabled and disabled, perform a
shutdown/no shutdown on the bundle.
• LFI is not supported
• Multiclass MLP is not supported
• The Cisco ASR 903 Router supports MLPPP statistics with the following limitations:
– Packet counters on the bundle display the number of fragments rather than packets.
– Control packets are accounted on the bundle.
• If you increase the maximum transmission unit (MTU) size on an MLPPP interface to a value higher
than the maximum received reconstructed unit (MRRU) value on the peer interface, this can bring
the MLPPP tunnel down. To restore the tunnel, perform a shutdown/no shutdown on the interface.
MPLS VPN Limitation
• MPLS VPN (L3VPN) Fragmentation does not function properly if an access interface has a higher
MTU value than a core interface. To ensure that fragmentation functions correctly, configure the
core interface MTU with a value that exceeds the access interface MTU and relevant headers.
OC-3 IM Limitations
• The configure replace command is not supported on the OC-3 IMs.
• SDH framing mode is supported; SONET is not supported.
• The optical interface module is designed for OC-3 and OC-12 traffic, but OC-12 functionality is not
currently supported.
• If you issue the no card type command on the controller, you must reload the router in order to
configure a new card type value.
• We recommend that you use Release 3.7.2 or later when using the OC-3 IM with high availability
(HA) features such as stateful switchover (SSO).
Pseudowire/AToM Limitation
• The Cisco ASR 903 Router supports ATM over MPLS N-to-one cell mode for a single ATM Virtual
Channel Connections (VCCs) or Permanent Virtual Circuits (PVCs) to a pseudowire, but does not
support mapping to multiple VCCs or PVCs.
• The Cisco ASR 903 Router does not support ATM over MPLS one-to-one cell mode.
• The Cisco ASR 903 Router supports pseudowire ping using the CW method; pseudowire ping using
the TTL method is not supported.
• The Cisco ASR 903 Router supports a maximum of 2000 pseudowires in any combination.
QoS Limitations
• For a description of QoS features and limitations on the Cisco ASR 903 Router in release 3.7S, see
http://www.cisco.com/en/US/docs/routers/asr903/software/guide/chassis/Release3.7.0S/ASR903-
Chassis-SW-37.html.

Cisco ASR 900 Series Specifications

General

Brand	Cisco
Model	ASR 900 Series
Category	Network Router
Language	English