Specifications

CHAPTER
5-1
Cisco ONS 15454 and Cisco ONS 15327 TL1 Command Guide, R3.3
May 2002
5
Ring Provisioning
This chapter provides information and sample procedures for setting up STS or VT circuits over existing
unidirectional path switched ring (UPSR) and bidirectional line switch ring (BLSR) configurations using
TL1, including:
• UPSR topology
• UPSR cross-connections
• Ring-to-ring interconnection
• 1WAY drop and continue
Note Because the ONS 15454/ONS 15327 implements logical UPSR, there are no defined east and west ports.
Instead, the east STS path for one circuit can exit a different port than the east STS path of another
circuit, even though the west STS paths for both circuits may share the same port.
5.1 UPSR Topology
No special configuration of the physical UPSR topology is required other than connecting the fibers to
the desired ports on the desired nodes. The east and west paths must exit a node at different ports (to
ensure link diversity), but there are no other physical topology restrictions
ONS 15xxx networks give you the option to set up path-protected mesh networks (PPMNs). PPMNs
extend the protection scheme of a UPSR from the basic ring configuration to the meshed architecture of
several interconnected rings. For more information about PPMN refer to the Cisco ONS 15454
Procedure Guide or the Cisco ONS 15327 User Documentation.
5.2 UPSR Cross-Connections
To create a UPSR cross-connection using TL1, you only need to designate whether it is a 1WAY or
2WAY cross-connect, but the access identifier (AID) must be more explicit. For example, to create a
1WAY UPSR circuit over the network with nodes A, B, C, and D and segments A-B, B-D, A-C, C-D as
shown in Figure 5-1, enter the following commands:
ENT-CRS-STS1:A:FROM,TO1&TO2:CTAG1::1WAY;
ENT-CRS-STS1:B:FROM,TO:CTAG2::1WAY;
ENT-CRS-STS1:C:FROM,TO:CTAG3::1WAY;
ENT-CRS-STS1:D:FROM1&FROM2,TO:CTAG4::1WAY;