Cisco ONS 15454 Installation and Operations Guide, Release 3.1
Chapter 5, SONET Configurations

Table Of Contents

SONET Topologies

5.1 Before You Begin

5.2 Bidirectional Line Switched Rings

5.2.1 Two-Fiber BLSRs

5.2.2 Four-Fiber BLSRs

5.2.3 BLSR Bandwidth

5.2.4 Sample BLSR Application

5.2.5 Setting Up BLSRs

5.2.6 Upgrading From Two-Fiber to Four-Fiber BLSRs

5.2.7 Adding and Removing BLSR Nodes

5.2.8 Moving BLSR Trunk Cards

5.3 Unidirectional Path Switched Rings

5.3.1 Example UPSR Application

5.3.2 Setting Up a UPSR

5.3.3 Adding and Removing UPSR Nodes

5.4 Subtending Rings

5.5 Linear ADM Configurations

5.6 Path-Protected Mesh Networks


SONET Topologies


This chapter explains how to set up the Cisco ONS 15454 in different SONET topologies, including:

Two-fiber and four-fiber bidirectional line switched rings (BLSRs)

Unidirectional path switched rings (UPSRs)

Subtending rings

Linear add/drop multiplexers (ADMs)

Path-protected mesh networks (PPMNs)

5.1 Before You Begin

To avoid errors during network configuration, Cisco recommends that you draw the complete ONS 15454 SONET topology on paper (or electronically) before you begin the physical implementation. A sketch ensures that you have adequate slots, cards, and fibers to complete the topology.

Table 5-1 shows the SONET rings that can be created on each ONS 15454 node.

Table 5-1 ONS 15454 Rings

Ring Type
Maximum per node

All rings

5

BLSRs

2

2-Fiber BLSR

2

4-Fiber BLSR

1

UPSR

4


5.2 Bidirectional Line Switched Rings

The ONS 15454 can support two concurrent BLSRs in one of the following configurations:

Two, two-fiber BLSRs, or

One two-fiber and one four-fiber BLSR.

Each BLSR can have up to 16 ONS 15454s. Because the working and protect bandwidths must be equal, you can create only OC-12 (two-fiber only), OC-48, or OC-192 BLSRs.


Note Two-fiber BLSRs can support up to 24 ONS 15454s, but switch times are slightly longer for rings containing more than 16 nodes. BLSRs with 16 or fewer nodes will meet the GR-1230 switch time requirement. Four-fiber BLSRs can only support 16 nodes.


5.2.1 Two-Fiber BLSRs

In two-fiber BLSRs, each fiber is divided into working and protect bandwidths. For example, in an OC-48 BLSR ( Figure 5-1), STSs 1 - 24 carry the working traffic, and STSs 25 - 48 are reserved for protection. Working traffic (STSs 1 - 24) travels in one direction on one fiber and in the opposite direction on the second fiber. The Cisco Transport Controller (CTC) circuit routing routines calculate the "shortest path" for circuits based on many factors, including requirements set by the circuit provisioner, traffic patterns, and distance. For example, in Figure 5-1, circuits going from Node 0 to Node 1 typically will travel on Fiber 1, unless that fiber is full, in which case circuits will be routed on Fiber 2 through Node 3 and Node 2. Traffic from Node 0 to Node 2 (or Node 1 to Node 3), may be routed on either fiber, depending on circuit provisioning requirements and traffic loads.

Figure 5-1 A four-node, two-fiber BLSR

The SONET K1 and K2 bytes carry the information that governs BLSR protection switches. Each BLSR node monitors the K bytes to determine when to switch the SONET signal to an alternate physical path. The K bytes communicate failure conditions and actions taken between nodes in the ring.

If a break occurs on one fiber, working traffic targeted for a node beyond the break switches to the protect bandwidth on the second fiber. The traffic travels in reverse direction on the protect bandwidth until it reaches its destination node. At that point, traffic is switched back to the working bandwidth.

Figure 5-2 shows a sample traffic pattern on a four-node, two-fiber BLSR.

Figure 5-2 Four-node, two-fiber BLSR sample traffic pattern

Figure 5-3 shows how traffic is rerouted following a line break between Node 0 and Node 3.

All circuits originating on Node 0 carried to Node 2 on Fiber 2 are switched to the protect bandwidth of Fiber 1. For example, a circuit carried on STS-1 on Fiber 2 is switched to STS-25 on Fiber 1. A circuit carried on STS-2 on Fiber 2 is switched to STS-26 on Fiber 1. Fiber 1 carries the circuit to Node 3 (the original routing destination). Node 3 switches the circuit back to STS-1 on Fiber 2 where it is routed to Node 2 on STS-1.

Circuits originating on Node 2 that were normally carried to Node 0 on Fiber 1 are switched to the protect bandwidth of Fiber 2 at Node 3. For example, a circuit carried on STS-2 on Fiber 1 is switched to STS-26 on Fiber 2. Fiber 2 carries the circuit to Node 0 where the circuit is switched back to STS-2 on Fiber 1 and then dropped to its destination.

Figure 5-3 Four-node, two-fiber BLSR traffic pattern following line break

5.2.2 Four-Fiber BLSRs

Four-fiber BLSRs double the bandwidth of two-fiber BLSRs. Because they allow span switching as well as ring switching, four-fiber BLSRs increase the reliability and flexibility of traffic protection. Two fibers are allocated for working traffic and two fibers for protection, as shown in Figure 5-4. To implement a four-fiber BLSR, you must install four OC-48 or OC-48AS cards, or four OC-192 cards at each BLSR node.

Figure 5-4 A four-node, four-fiber BLSR

Four-fiber BLSRs provide span and ring switching:

Span switching ( Figure 5-5) occurs when a working span fails. Traffic switches to the protect fibers between the nodes (Node 0 and Node 1 in the Figure 5-5 example) and then returns to the working fibers. Multiple span switches can occur at the same time.

Ring switching ( Figure 5-6) occurs when a span switch cannot recover traffic, such as when both the working and protect fibers fail on the same span. In a ring switch, traffic is routed to the protect fibers throughout the full ring.

Figure 5-5 A four-fiber BLSR span switch

Figure 5-6 A four-fiber BLSR ring switch

5.2.3 BLSR Bandwidth

BLSR nodes can terminate traffic that is fed from either side of the ring. Therefore, BLSRs are suited for distributed node-to-node traffic applications such as interoffice networks and access networks.

BLSRs allow bandwidth to be reused around the ring and can carry more traffic than a network with traffic flowing through one central hub. BLSRs can also carry more traffic than a UPSR operating at the same OC-N rate. Table 5-2 shows the bidirectional bandwidth capacities of two-fiber BLSRs. The capacity is the OC-N rate divided by two, multiplied by the number of nodes in the ring minus the number of pass-through STS-1 circuits. Table 5-3 shows the bidirectional bandwidth capacities of four-fiber BLSRs.

Table 5-2 Two-Fiber BLSR Capacity

OC Rate
Working Bandwidth
Protection Bandwidth
Ring Capacity

OC-12

STS1-6

STS 7-12

6 x N1 - PT2

OC-48

STS 1-24

STS 25-48

24 x N - PT

OC-192

STS 1-96

STS 97-192

96 x N - PT

1 N equals the number of ONS 15454 nodes configured as BLSR nodes.

2 PT equals the number of STS-1 circuits passed through ONS 15454 nodes in the ring (capacity can vary depending on the traffic pattern).


Table 5-3 Four-Fiber BLSR Capacity

OC Rate
Working Bandwidth
Protection Bandwidth
Ring Capacity

OC-48

STS 1-48 (Fiber 1)

STS 1-48 (Fiber 2)

48 x N - PT

OC-192

STS 1-192 (Fiber 1)

STS 1-192 (Fiber 2)

192 x N - PT


Figure 5-7 shows an example of BLSR bandwidth reuse. The same STS carries three different traffic sets simultaneously on different spans on the ring: one set from Node 3 to Node 1, one from Node 1 to Node 2, and another from Node 2 to Node 3.

Figure 5-7 BLSR bandwidth reuse

5.2.4 Sample BLSR Application

Figure 5-8 shows a sample two-fiber BLSR implementation. A regional long-distance network connects to other carriers at Node 0. Traffic is delivered to the service provider's major hubs.

Carrier 1 delivers six DS-3s over two OC-3 spans to Node 0. Carrier 2 provides twelve DS-3s directly. Node 0 receives the signals and delivers them around the ring to the appropriate node.

The ring also brings 14 DS-1s back from each remote site to Node 0. Intermediate nodes serve these shorter regional connections.

The ONS 15454 OC-3 card supports a total of four OC-3 ports so that two additional OC-3 spans can be added at little cost.

Figure 5-8 A five-node BLSR

Figure 5-9 shows the shelf assembly layout for Node 0, which has one free slot. Figure 5-10 shows the shelf assembly layout for the remaining sites in the ring. In this BLSR configuration, an additional eight DS-3s at Node IDs 1 and 3 can be activated. An additional four DS-3s can be added at Node ID 4, and ten DS-3s can be added at Node ID 2. Each site has free slots for future traffic needs.

Figure 5-9 Shelf assembly layout for Node 0 in Figure 5-8

Figure 5-10 Shelf assembly layout for Nodes 1 - 4 in Figure 5-8

5.2.5 Setting Up BLSRs

To set up a BLSR on the ONS 15454, you perform five basic procedures:

Install the BLSR trunk cards. See the "Install the BLSR Trunk Cards" procedure.

Create the BLSR DCC terminations. See the "Create the BLSR DCC Terminations" procedure.

Enable the BLSR ports. See the "Enable the BLSR Ports" procedure.

Set up BLSR timing. See the "Set up ONS 15454 Timing" procedure on page 3-14.

Provision the BLSR. See the "Provision the BLSR" procedure.

Procedure: Install the BLSR Trunk Cards


Step 1 Install the OC-12, OC-48, OC-48AS, or OC-192 cards that will serve as the BLSR trunk cards. You can install the OC-12 and OC-48AS cards in any slot, but you can install the OC-48 and OC-192 cards only in Slots 5, 6, 12, or 13.

Step 2 Allow the cards to boot.

Step 3 Attach the fiber to the east and west BLSR ports at each node.

Plan your fiber connections and use the same plan for all BLSR nodes. For example, make the east port the farthest slot to the right and the west port the farthest left. Plug fiber connected to an east port at one node into the west port on an adjacent node. Figure 5-11 shows fiber connections for a two-fiber BLSR with trunk cards in Slot 5 (west) and Slot 12 (east).


Note Always plug the transmit (Tx) connector of an OC-N card at one node into the receive (Rx) connector of an OC-N card at the adjacent node. Cards will display an SF LED if Tx and Rx connections are mismatched.


For four-fiber BLSRs, use the same east - west connection pattern for the working and protect fibers. Do not mix working and protect card connections. The BLSR will not function if working and protect cards are interconnected. Figure 5-12 shows fiber connections for a four-fiber BLSR. Slot 5 (west) and Slot 12 (east) carry the working traffic. Slot 6 (west) and Slot 13 (east) carry the protect traffic.

Figure 5-11 Connecting fiber to a four-node, two-fiber BLSR

Figure 5-12 Connecting fiber to a four-node, four-fiber BLSR


Procedure: Create the BLSR DCC Terminations


Step 1 Log into the first node that will be in the BLSR.

Step 2 Click the Provisioning > Sonet DCC tabs.

Step 3 In the SDCC Terminations section, click Create.

Step 4 On the Create SDCC Terminations dialog, press Ctrl and click the two slots/ports that will serve as the BLSR ports at the node. For example, Slot 5 (OC-48)/Port 1 and Slot 12 (OC-48)/ Port 1. For four-fiber BLSRs, provision the working cards, but not the protect cards, as DCC terminations.

Step 5 Click OK.

Step 6 The slots/ports appear in the SDCC Terminations list.

Step 7 Complete Steps 2 - 5 at each node that will be in the BLSR.


Note The ONS 15454 uses the SONET Section layer DCC (SDCC) for data communications. It does not use the Line DCCs; therefore, the Line DCCs are available to tunnel DCCs from third-party equipment across ONS 15454 networks. For more detail, see the "Creating DCC Tunnels" section on page 6-21.



Procedure: Enable the BLSR Ports


Step 1 Log into one of the nodes that will be in the BLSR.

Step 2 Double-click one of the OC-N cards that you configured as a DCC termination.

Step 3 Click the Provisioning > Line tabs.

Step 4 Click Status ( Figure 5-13) and choose In Service.

Figure 5-13 Enabling an optical port

Step 5 Repeat Steps 2 - 4 for the other optical card configured as a DCC termination.

Step 6 (Four-fiber BLSR only) Repeat Steps 2 - 4 for each protect card.

Step 7 Repeat Steps 2 - 5 at each node that will be in the BLSR.


After configuring the SONET DCC, set the timing for the node. For procedures, see the "Setting Up ONS 15454 Timing" section on page 3-12. After you configure the timing you can provision the BLSR.

Procedure: Provision the BLSR


Step 1 Log into one BLSR node.

Step 2 Select the Provisioning > Ring tabs.

Step 3 Click Create.

Step 4 On the Create BLSR dialog box ( Figure 5-14), set the BLSR properties:

Ring Type—select the BLSR ring type, either two-fiber or four-fiber.

Ring ID—Assign a ring ID (a number between 0 and 9999). Nodes in the same BLSR must have the same Ring ID.

Node ID—Assign a Node ID. The Node ID identifies the node to the BLSR. Nodes in the same BLSR must have unique Node IDs.

Reversion time—Set the amount of time that will pass before the traffic reverts to the original working path. The default is 5 minutes. All nodes in a BLSR ring should have the same reversion time setting, particularly if "never" (i.e., non-revertive) is selected.

West Port—Assign the west BLSR port for the node from the pull-down menu. (In Figure 5-11, this is Slot 5.)

East Port—Assign the east BLSR port for the node from the pull-down menu. (In Figure 5-11, this is Slot 12.)

The east and west ports must match the fiber connections and DCC terminations set up in the "Install the BLSR Trunk Cards" procedure and the "Create the BLSR DCC Terminations" procedure.

For four-fiber BLSRs, complete the following:

Span Reversion—Set the amount of time that will pass before the traffic reverts to the original working path following a span reversion. The default is 5 minutes. Span reversions can be set to Never. If you set a reversion time, the times must be the same for both ends of the span. That is, if Node A's west fiber is connected to Node B's east port, the Node A west span reversion time must be the same as the Node B east span reversion time. To avoid reversion time mismatches, Cisco recommends that you use the same span reversion time throughout the ring.

West Protect—Assign the west BLSR port that will connect to the west protect fiber from the pull-down menu. (In Figure 5-12, this is Slot 6.)

East Protect—Assign the east BLSR port that will connect to the east protect fiber from the pull-down menu. (In Figure 5-12, this is Slot 13.)

Figure 5-14 Setting BLSR properties

Step 5 Click OK.


Note Some or all of the following alarms display during BLSR setup: E-W MISMATCH, RING MISMATCH, APSCIMP, APSDFLTK, BLSROSYNC. The alarms will clear after you configure all the nodes in the BLSR.


Step 6 Complete Steps 2 - 5 at each node that you are adding to the BLSR.

Step 7 After you configure the last BLSR node, wait for the BLSR Ring Map Change dialog box to display (this can take 10 - 30 seconds).


Note The dialog box will not display if SDCC Termination alarms (e.g., EOC) or BLSR alarms (such as E-W MISMATCH and RING MISMATCH) are present. If an SDCC alarm is present, review the DCC provisioning at each node; use the "Create the BLSR DCC Terminations" procedure. If BLSR alarms have not cleared, repeat Steps 1 - 6 at each node, making sure each node is provisioned correctly. You can also following alarm troubleshooting procedures provided in the Cisco ONS 15454 Troubleshooting and Maintenance Guide.


Step 8 On the BLSR Ring Map Change dialog, click Yes.

Step 9 On the BLSR Ring Map dialog box, verify that the ring map contains all the nodes you provisioned in the expected order. If so, click Accept. If the nodes do not appear, or are not in the expected order, repeat Steps 1 - 8, making sure no errors are made.

Step 10 Switch to network view and verify the following:

A green span line appears between all BLSR nodes

All E-W MISMATCH, RING MISMATCH, APSCIMP, DFLTK, and BLSROSYNC alarms are cleared.

Step 11 Test the BLSR using testing procedures normal for your site. Here are a few steps you can use:

a. Run test traffic through the ring.

b. Log into a node, click the Maintenance > Ring tabs, and choose MANUAL RING from the East Switch list. Click Apply.

c. In network view, click the Conditions tab and click Retrieve. You should see a Ring Switch West event, and the far-end node that responded to this request will report a Ring Switch East event.

d. Verify that traffic switches normally.

e. Choose Clear from the East Switch list and click Apply.

f. Repeat Steps a - d for the West Switch.

g. Disconnect the fibers at one node and verify that traffic switches normally.


5.2.6 Upgrading From Two-Fiber to Four-Fiber BLSRs

Two-fiber OC-48 or OC-192 BLSRs can be upgraded to four-fiber BLSRs. To upgrade, you install two OC-48 or OC-192 cards at each two-fiber BLSR node, then log into CTC and upgrade each node from two-fiber to four-fiber. The fibers that were divided into working and protect bandwidths for the two-fiber BLSR are now fully allocated for working BLSR traffic.

Procedure: Upgrade From a Two-Fiber to a Four-Fiber BLSR


Step 1 Log into one of the two-fiber BLSR nodes. In network view:

a. Verify that all spans between BLSR nodes on the network map are green.

b. Click the Alarms tab. Verify that no critical or major alarms are present, nor any facility alarms, such as LOS, LOF, AIS-L, SF, and SD. In a BLSR, these facility conditions may be reported as minor alarms.

c. Click the Conditions tab, then click Retrieve Conditions. Verify that no ring switches are active.

If trouble is indicated, for example, a major alarm exists, resolve the problem before proceeding to Step 2. See the Cisco ONS 15454 Troubleshooting and Maintenance Guide for additional information.

Step 2 Install two OC-48 or OC-192 cards at each BLSR node. You must install the same OC-N card rate as the two fiber.

Step 3 Enable the ports for each new OC-N card:

a. Display the card in card view.

b. Click the Provisioning > Line tabs.

c. Click Status and choose In Service.

d. Click Apply.

e. Repeat Steps a - d for each new OC-N card at each BLSR node.

Step 4 Connect the fiber to the new cards. Use the same east - west connection scheme that was used to create the two-fiber connections. Figure 5-12 shows an example.

Step 5 Test the new fiber connections using procedures standard for your site. For example, pull a Tx fiber for a protect card and verify that an LOS alarm displays for the appropriate Rx card. Do this fiber test for every span in the BLSR protect ring.

Step 6 Perform a span lockout at each BLSR node:

a. At one of the BLSR nodes, switch to node view. Click the Maintenance > Ring tabs.

b. Under West Switch for the two-fiber BLSR you will convert, select LOCKOUT SPAN. Click Apply

c. Under East Switch, select LOCKOUT SPAN. Click Apply.

d. Repeat Steps a - c at each node in the two-fiber BLSR.

Step 7 Upgrade each node from two-fiber to four-fiber BLSR:

a. At one of the BLSR nodes, switch to node view. Click the Provisioning > Ring tabs.

b. Select the two-fiber BLSR. Click Upgrade.

c. On the Upgrade BLSR dialog box, complete the following:

Span Reversion—Set the amount of time that will pass before the traffic reverts to the original working path following a span reversion. The default is 5 minutes.

West Protect—Assign the east BLSR port that will connect to the east protect fiber from the pull-down menu. (In Figure 5-12, this is Slot 6.)

East Protect—Assign the east BLSR port that will connect to the east protect fiber from the pull-down menu. (In Figure 5-12, this is Slot 13.)

d. Click Ok.

e. Complete Steps a - d at each two-fiber BLSR node.

Step 8 Clear the span lockout:

a. Display a BLSR node in node view. Click the Maintenance > Ring tabs.

b. Under West Switch, select CLEAR. Click Apply

c. Under East Switch, select CLEAR. Click Apply.

d. Repeat Steps a - c at each node in the new four-fiber BLSR.

e. Switch to network view. Verify that no critical or major alarms are present, nor any facility alarms, such as LOS, LOF, AIS-L, SF, and SD. If an alarm is present, resolve the problem using procedures in the Cisco ONS 15454 Troubleshooting and Maintenance Guide.

Step 9 Test the four-fiber BLSR using procedures in Step 11 in the "Provision the BLSR" procedure.


5.2.7 Adding and Removing BLSR Nodes

This section explains how to add and remove BLSR nodes. To add or remove a node, you force a protection switch to route traffic away from the span where you will add or remove the node. Figure 5-15 shows a three-node BLSR before the new node is added. To add Node 3, you would:

Force a protection switch on the Node 1 (Slot 5, West) and Node 4 (Slot 12, East) span. The protection switch forces traffic away from the fibers that you will remove and reconnect to the added node.

Remove fibers from Node 1/Slot 5 and Node 4/Slot 12, then, using additional fibers, connect Node 1 and Node 4 to Node 3.

Remove the protection switch to route traffic through the added node.


Note You can only add one node at a time to an ONS 15454 BLSR.


Figure 5-15 A three-node BLSR before adding a new node

Procedure: Add a BLSR Node

Perform these steps on-site and not from a remote location.


Step 1 Draw a diagram, similar to Figure 5-15, for the BLSR installation where you will add the node. In the diagram, identify the nodes, cards (slots) and spans (east or west) that will connect to the new node. This information is essential to complete this procedure without error. For example, in Figure 5-15, you would circle Slot 5 (west) on Node 1, and Slot 12 (east) on Node 4.

Step 2 Log into CTC and display the BLSR nodes in network view. Verify the following:

All BLSR spans on the network map are green.

On the Alarms tab, no critical or major alarms are present, nor any facility alarms, such as LOS, LOF, AIS-L, SF, and SD. In a BLSR, these facility conditions may be reported as minor alarms.

On the Conditions tab, no ring switches are active.

If trouble is indicated, for example, a major alarm exists, resolve the problem before proceeding.

Step 3 Install the OC-N cards in the ONS 15454 that you will add to the BLSR; use the "Install the BLSR Trunk Cards" procedure. Ensure fiber cables are available to connect to the cards. Run test traffic through the node to ensure the cards are functioning properly.

Step 4 Log into the new node and complete the BLSR setup.

Provision the SONET DCC using the "Create the BLSR DCC Terminations" procedure.

Configure the BLSR timing using the "Set up ONS 15454 Timing" procedure on page 3-14.

Enable the BLSR ports using the "Enable the BLSR Ports" procedure.

Provision the BLSR using the "Provision the BLSR" procedure

Step 5 Log into the node that will connect to the new node through its east port (Node 4 in the Figure 5-15 example).

Step 6 Switch protection on the east port:

a. Click the Maintenance > Ring tabs.

b. From the East Switch list, choose FORCE RING. Click Apply.

Performing a FORCE switch generates a manual switch request on an equipment (MANUAL-REQ) alarm. This is normal.


Caution Traffic is unprotected during a protection switch.

Step 7 Log into the node that will connect to the new node through its west port (Node 1 in the Figure 5-15 example).

Step 8 Switch protection on the west port:

a. Click the Maintenance > Ring tabs.

b. From the West Switch list, choose FORCE RING. Click Apply.

Step 9 Following the diagram that you created in Step 1, remove the fiber connections from the two nodes that will connect directly to the new node.

a. Remove the east fiber from the node that will connect to the west port of the new node. In the Figure 5-15 example, this is Node 4/Slot 12.

b. Remove the west fiber from the node that will connect to the east port of the new node. In the Figure 5-15 example, this is Node 1/Slot 5.

Step 10 Replace the removed fibers with fibers that are connected to the new node. Connect the west port to the east port and the east port to the west port. Figure 5-16 shows the BLSR in the Figure 5-15 example after the node is connected.

Figure 5-16 A BLSR with a newly-added fourth node

Step 11 Log out of CTC and then log back into any node in the BLSR.

Step 12 In node view, select the Provisioning > Ring tabs and click Ring Map.

Step 13 On the BLSR Map Ring Change dialog box, click Yes.

Step 14 On the BLSR Ring Map dialog box, verify that the new node is added. If it is, click Accept. If it does not appear, log into the new node. Verify that the BLSR is provisioned correctly according to the "Provision the BLSR" procedure, then repeat Steps 12 - 13. If the node still does not appear, repeat the steps in the procedure making sure that no errors were made.

Step 15 From the Go To menu, select Network View. Click the Circuits tab. Wait until all the circuits are discovered. The circuits that pass through the new node will be shown as incomplete.

Step 16 In network view, right-click the new node and select Update Circuits With The New Node from the shortcut menu. Verify that the number of updated circuits displayed in the dialog box is correct.

Step 17 Select the Circuits tab and verify that no incomplete circuits are present.

Step 18 Clear the protection switch for the node that is using its east port to connect to the new node, and for the node that is using its west port to connect to the new node.

a. To clear the protection switch from the east port, display the Maintenance > Ring tabs. From the East Switch list choose CLEAR. Click Apply.

b. To clear the protection switch from the west port, choose CLEAR from the West Switch list. Click Apply.


Procedure: Remove a BLSR Node


Caution The following procedure minimizes traffic outages during node deletions, but traffic will be lost when you delete and recreate circuits that passed through the deleted node.


Step 1 Before you start this procedure, make sure you know the following:

Which node is connected through its east port to the node that will be deleted. For example if you are deleting Node 1 in Figure 5-16, Node 3 is the node connected through its east port to Node 1.

Which node is connected through its west port to the node that will be deleted. In Figure 5-16, Node 2 is connected to Node 1 through its west port.

Step 2 Log into a node on the same BLSR as the node you will remove. (Do not log into the node that you will remove.)

Step 3 Display the BLSR nodes in network view and verify the following:

All BLSR spans on the network map are green.

No critical or major alarms (LOF, LOS, ASP, ASL) are displayed on the Alarms tab.

On the Conditions tab, no ring switches are active.

If trouble is indicated, for example, a critical or major alarm exists, resolve the problem before proceeding.

Step 4 Display the node that you will remove in node view.

Step 5 Delete all the circuits that originate or terminate in that node. (If a circuit has multiple drops, delete only the drops that terminate on the node you want to delete.)

a. Click the Circuits tab. The circuits that use this node are displayed.

b. Select circuits that originate or terminate on the node. Click Delete.

c. Click Yes when prompted.

d. If a multidrop circuit has drops at the node that will be removed, select the circuit, click Edit, and remove the drops.

Step 6 Complete this step if circuits that were created using Cisco Transport Controller Release 2.x. pass through the node that will be deleted (i.e., circuits are displayed on the Circuits tab).

a. On the Circuits tab of the node that will be deleted, select a circuit and click Edit.

b. On the Edit Circuits window, check Show Detailed Map.

c. Verify that the circuits enter and exit the node on the same STS. For example, if a circuit enters on s5/p1/S1 (Slot 5, Port 1, STS1), verify that it exits on STS1. If a circuit enters/exits on different STSs, write down the name of the circuit. You will delete and recreate these circuits in Step e.

d. From the View menu select Go to Network View, then select the Circuits tab.

e. Delete and recreate each circuit recorded in Step c. To delete the circuit, select the circuit on the Circuits window and click the Delete button. To create the circuit, go to the "Create an Automatically Routed Circuit" procedure on page 6-2.

f. Repeat Steps a - e for each circuit displayed on the Circuits tab.

Step 7 Use information recorded in Step 1 to switch traffic away from the ports of neighboring nodes that will be disconnected when the node is removed:


Caution Traffic is unprotected during the protection switch.

a. Open the neighboring node that is connected through its east port to the removed node.

b. Click the Maintenance > Ring tabs.

c. From the East Switch list, choose FORCE RING. Click Apply.

d. Open the node that is connected through its west port to the removed node.

e. Click the Maintenance > Ring tabs.

f. From the West Switch list, choose FORCE RING. Click Apply.

Step 8 Remove all fiber connections between the node being removed and the two neighboring nodes.

Step 9 Reconnect the two neighboring nodes directly, west port to east port.

Step 10 Close CTC, then log into a node on the reduced ring.

Step 11 Wait for the BLSR Map Ring Change dialog box to display. (If the dialog box does not display after
10 - 15 seconds, select the Provisioning > Ring tabs and click Ring Map.) When the dialog box displays, click Yes.

Step 12 On the BLSR Ring Map dialog box, click Accept.

Step 13 Clear the protection switches on the neighboring nodes:

a. Open the node with the protection switch on its east port.

b. Click the Maintenance > Ring tabs and choose CLEAR from the East Switch list. Click Apply.

c. Open the node with the protection switch on its west port.

d. Click the Maintenance > Ring tabs and choose CLEAR from the West Switch list. Click Apply.

Step 14 If a BITS clock is not used at each node, check that the synchronization is set to one of the eastbound or westbound BLSR spans on the adjacent nodes. If the removed node was the BITS timing source, use a new node as the BITS source or select internal synchronization at one node where all other nodes will derive their timing. (For information about ONS 15454 timing, see the "Setting Up ONS 15454 Timing" section on page 3-12.)


5.2.8 Moving BLSR Trunk Cards


Caution Call the Technical Assistance Center (1-877-323-7368) before performing this procedure to ensure that circuit and provisioning data is preserved.


Caution To change BLSR trunk cards, you will drop one node at a time from the current BLSR. This procedure is service affecting during the time needed to complete the steps below. This applies to all BLSR nodes where cards will change slots. Review all the steps before you proceed.

Figure 5-17 shows a four node OC-48 BLSR using trunk cards in Slots 6 and 12 at all four nodes. Trunk cards will be moved at Node 4 from Slots 6 and 12 to Slots 5 and 6. To do this Node 4 is temporarily removed from the active BLSR while the trunk cards are switched.

Figure 5-17 A four-node BLSR before a trunk card switch

Figure 5-18 shows the BLSR after the cards are switched.

Figure 5-18 A four-node BLSR after the trunk cards are switched at one node

Procedure: Move a BLSR Trunk Card

Use the following steps to move one BLSR trunk card to a different slot. Use this procedure for each card you want to move. Although the procedure is for OC-48 BLSR trunk cards, you can use the same procedure for OC-12, OC-48AS, and OC-192 cards.


Note The ONS 15454 nodes must have CTC Release 2.0 or later and cannot have active alarms for the OC-48 or OC-12 cards or the BLSR configuration.



Step 1 Log into CTC and display the BLSR nodes in network view. Verify the following:

All BLSR spans on the network map are green.

On the Alarms tab, no critical or major alarms are present, nor any facility alarms, such as LOS, LOF, AIS-L, SF, and SD. In a BLSR, these facility conditions may be reported as minor alarms.

On the Conditions tab, no ring switches are active.

If trouble is indicated, for example, a critical or major alarm exists, resolve the problem before proceeding. Refer to the Cisco ONS 15454 Troubleshooting and Maintenance Guide for alarm troubleshooting procedures.

Step 2 Switch traffic away from the node where the trunk card will be switched:

a. Log into the node that is connected through its east port to the node where the trunk card will be moved. (In the Figure 5-17 example, this is Node 1.) Click the Maintenance > Ring tabs.

b. From the East Switch list, choose FORCE RING. Click Apply.

When you perform a manual switch, a manual switch request equipment alarm (MANUAL-REA) is generated. This is normal.


Caution Traffic is unprotected during a protection switch.

c. Log into the node that is connected through its west port to the node where the trunk card will be moved. (In the Figure 5-17 example, this is Node 3.) Click the Maintenance > Ring tabs.

d. From the West Switch list, choose FORCE RING. Click Apply.

Step 3 Log into the node where the trunk card you will move is installed.

Step 4 Click the Circuits tab ( Figure 5-19). Write down the circuit information or, from the File menu, select Print or Export to print or export the information; you will need it to restore the circuits later. See the "Printing and Exporting CTC Data" section on page 2-26 for more information.

Figure 5-19 Deleting circuits from a BLSR trunk card

Step 5 Delete the circuits on the card you are removing:

a. Highlight the circuit(s). To select multiple circuits, press the Shift or Ctrl key.

b. Click Delete.

c. On the Delete Circuit dialog box, click Yes.

Step 6 Delete the SONET DCC termination on the card you are removing:

a. Click the Provisioning > Sonet DCC tabs.

b. From the SDCC Terminations list, click the SONET DCC you need to delete and click Delete.

Step 7 Disable the ring on the current node:

a. Click the Provisioning > Ring tabs.

b. Highlight the ring and click Delete.

c. On the confirmation message, confirm that this is the ring you want to delete. If so, click Yes.

Step 8 If an OC-N card is a timing source, select the Provisioning > Timing tabs and set timing to Internal.

Step 9 Place the ports on the card out of service:

a. Double-click the card.

b. On the Provisioning > Line tabs in the Status section, choose Out of Service for each port.

Step 10 Physically remove the card.

Step 11 Insert the card into its new slot and wait for the card to boot.

Step 12 To delete the card from its former slot, right-click the card in node view and select Delete from the list of options.

Step 13 Place the port(s) back in service:

a. To open the card, double-click or right-click the card and select Open.

b. Click the Provisioning tab.

c. From Status choose In Service.

d. Click Apply.

Step 14 Follow the steps described in the "Setting Up BLSRs" section to reenable the ring using the same cards (in their new slots) and ports for east and west. Use the same BLSR Ring ID and Node ID that was used before the trunk card was moved.

Step 15 Recreate the circuits that were deleted. See the "Create an Automatically Routed Circuit" procedure on page 6-2 for instructions.

Step 16 If you use line timing and the card you are moving is a timing reference, reenable the timing parameters on the card. See the "Set up ONS 15454 Timing" procedure on page 3-14 for instructions.


5.3 Unidirectional Path Switched Rings

UPSRs provide duplicate fiber paths around the ring. Working traffic flows in one direction and protection traffic flows in the opposite direction. If a problem occurs in the working traffic path, the receiving node switches to the path coming from the opposite direction.

CTC automates ring configuration. UPSR traffic is defined within the ONS 15454 on a circuit-by-circuit basis. If a path-protected circuit is not defined within a 1+1 or BLSR line protection scheme and path protection is available and specified, CTC uses UPSR as the default.

Figure 5-20 shows a basic UPSR configuration. If Node ID 0 sends a signal to Node ID 2, the working signal travels on the working traffic path through Node ID 1. The same signal is also sent on the protect traffic path through Node ID 3. If a fiber break occurs ( Figure 5-21), Node ID 2 switches its active receiver to the protect signal coming through Node ID 3.

Because each traffic path is transported around the entire ring, UPSRs are best suited for networks where traffic concentrates at one or two locations and is not widely distributed. UPSR capacity is equal to its bit rate. Services can originate and terminate on the same UPSR, or they can be passed to an adjacent access or interoffice ring for transport to the service-terminating location.

Figure 5-20 A basic four-node UPSR

Figure 5-21 A UPSR with a fiber break

5.3.1 Example UPSR Application

Figure 5-22 shows a common UPSR application. OC-3 optics provide remote switch connectivity to a host TR-303 switch. In the example, each remote switch requires eight DS-1s to return to the host switch. Figure 5-23 and Figure 5-24 show the shelf layout for each site.

Figure 5-22 An OC-3 UPSR

Node ID 0 has four DS1-14 cards to provide 56 active DS-1 ports. The other sites only require two DS1-14 cards to handle the eight DS-1s to and from the remote switch. You can use the other half of each ONS 15454 shelf assembly to provide support for a second or third ring to other existing or planned remote sites.

In this sample OC-3 UPSR, Node ID 0 contains four DS1-14 cards and two OC3 IR 4 1310 cards. Six free slots also exist in this setup and can be provisioned with cards or left empty. Figure 5-23 shows the shelf setup for these cards.

Figure 5-23 Layout of Node ID 0 in the OC-3 UPSR example (Figure 5-15)

In the Figure 5-22 example, Nodes IDs 1 - 3 each contain two DS1-14 cards and two OC3 4 IR 1310 cards. Eight free slots exist. They can be provisioned with other cards or left empty. Figure 5-24 shows the shelf assembly setup for this configuration sample.

Figure 5-24 Layout of Node IDs 1 - 3 in the OC-3 UPSR example (Figure 5-15)

5.3.2 Setting Up a UPSR

To set up a UPSR, you perform four basic procedures:

Install the UPSR trunk cards. Use the "Install the UPSR Trunk Cards" procedure

Create the DCC terminations. Use the "Configure the UPSR DCC Terminations" procedure.

Configure the timing. Use the "Setting Up ONS 15454 Timing" section on page 3-12.

Enable the ports. Use the "Enable the UPSR Ports" procedure.

After you enable the ports, you set up the UPSR circuits. UPSR signal thresholds—the levels that determine when the UPSR path is switched—are set at the circuit level. To create UPSR circuits, see the "Circuits Overview" section on page 6-1.

Procedure: Install the UPSR Trunk Cards


Step 1 Install the OC-N cards that will serve as the UPSR trunk cards. You can install the OC-3, OC-12, and OC-48AS cards in any slot, but the OC-48 and OC-192 cards can only be installed in Slots 5, 6, 12, or 13.

Step 2 Allow the cards to boot.

Step 3 Attach the fiber to the east and west UPSR ports at each node.

To avoid errors, make the east port the farthest slot to the right and the west port the farthest left. Fiber connected to an east port at one node must plug into the west port on an adjacent node. Figure 5-25 shows fiber connections for a four-node UPSR with trunk cards in Slot 5 (west) and Slot 12 (east).

Always plug the fiber plugged into the transmit (Tx) connector of an OC-N card at one node into the receive (Rx) connector of an OC-N card at the adjacent node. The card will display an SF LED if Tx and Rx fibers are mismatched.

Figure 5-25 Connecting fiber to a four-node UPSR


Procedure: Configure the UPSR DCC Terminations


Step 1 Log into the first node that will be in the UPSR.

Step 2 Click the Provisioning > Sonet DCC tabs.

Step 3 In the SDCC Terminations section, click Create.

Step 4 On the Create SDCC Terminations dialog box, press Control and click the two slots/ports that will serve as the UPSR ports at the node. For example, Slot 6 (OC-48)/Port 1 and Slot 12 (OC-48)/Port 1.


Note The ONS 15454 uses the SONET Section layer DCC (SDCC) for data communications. It does not use the Line DCCs. Line DCCs can be used to tunnel DCCs from third party equipment across ONS 15454 networks. For procedures, see the "Creating DCC Tunnels" section on page 6-21.


Step 5 Click OK.

The slots/ports display in the SDCC Terminations section.

Step 6 Complete Steps 2 - 5 at each node that will be in the UPSR.


After configuring the SONET DCC, set the timing for the node. For procedures, see the "Setting Up ONS 15454 Timing" section on page 3-12. After configuring the timing, enable the UPSR ports as described in the following procedure.

Procedure: Enable the UPSR Ports


Step 1 Log into the first UPSR node.

Step 2 Double-click one of the cards that you configured as an SDCC termination.

Step 3 Click the Provisioning > Line tabs.

Step 4 Under Status, select In Service for each port that you want enabled.

Step 5 Repeat Steps 2 - 4 for the second card.

Step 6 Click Apply.


You configured a UPSR for one node. Use the same procedures to configure the additional nodes. To create path-protected mesh networks, see the "Path-Protected Mesh Networks" section. To create circuits, see the "Circuits Overview" section on page 6-1.

5.3.3 Adding and Removing UPSR Nodes

This section explains how to add and remove nodes in an ONS 15454 UPSR configuration. To add or remove a node, you switch traffic on the affected spans to route traffic away from the area of the ring where service will be performed. Use the span selector switch option to switch traffic from a UPSR span at different protection levels. The span selector switch option is useful when you need to reroute traffic from a UPSR span temporarily to add or drop nodes, perform maintenance, or perform other operations.

Procedure: Switch UPSR Traffic


Step 1 Display the network view.

Step 2 Right-click the span that will be cut to add or delete a node and select Circuits from the shortcut menu ( Figure 5-26).

Figure 5-26 Using the span shortcut menu to display circuits

Step 3 On the Circuits on Span dialog box ( Figure 5-27), select the protection from the Switch all UPSR circuits away menu:

CLEAR removes a previously-set switch command.

MANUAL switches the span if the new span is error free.

FORCE forces the span to switch, regardless of whether the new span is error free.

LOCKOUT locks out or prevents switching to a highlighted span. (LOCKOUT is only available when Revertive traffic is enabled.)


Caution FORCE and LOCKOUT commands override normal protective switching mechanisms. Applying these commands incorrectly can cause traffic outages.

Figure 5-27 Switching UPSR circuits

Step 4 Click Apply.

Step 5 When the confirmation dialog box appears, click OK to confirm the protection switching. The column under Switch State changes to your chosen level of protection.

Step 6 Click Close after Switch State changes.


Procedure: Add a UPSR Node


Note You can add only one node at a time. Perform these steps onsite and not from a remote location.



Step 1 Log into CTC and display the UPSR nodes in network view. Verify the following:

All UPSR spans on the network map are green.

No critical or major alarms (LOF, LOS, ASP, ASL) are displayed on the Alarms tab.

On the Conditions tab, no UPSR switches are active.

At each physical UPSR node, all fibers are securely connected to the appropriate ports.

If trouble is indicated, for example, a critical or major alarm exists, resolve the problem before proceeding.

Step 2 At the node that will be added to the UPSR:

Verify that the OC-N cards are installed and fiber is available to connect to the other nodes.

Run test traffic through the cards that will connect to the UPSR.

Use the "Setting Up a UPSR" section to provision the new node.

Step 3 Log into a node that will directly connect to the new node.

Step 4 Use the "Switch UPSR Traffic" procedure to initiate a FORCE switch to switch traffic away from the span that will connect to the new node.


Caution Traffic is not protected during a protection switch.

Step 5 Two nodes will connect directly to the new node; remove their fiber connections:

a. Remove the east fiber connection from the node that will connect to the west port of the new node.

b. Remove the west fiber connection from the node that will connect to the east port of the new node.

Step 6 Replace the removed fiber connections with connections from the new node.


Note Perform this step on site at the new node.


Step 7 Log out of CTC and then log back in.

Step 8 Display the network view. The new node should appear in the network map. Wait for a few minutes to allow all the nodes to appear.

Step 9 Click the Circuits tab and wait for all the circuits to appear, including spans. The affected circuit will display as "incomplete."

Step 10 In the network view, right-click the new node and select Update Circuits With New Node from the list of options. Wait for the confirmation dialog box to appear. Verify that the number of updated circuits displayed in the dialog box is correct.

Step 11 Select the Circuits tab and verify that no incomplete circuits are displayed. If incomplete circuits are displayed, repeat Step 9.

Step 12 Use the "Switch UPSR Traffic" procedure to clear the protection switch.


Procedure: Remove a UPSR Node


Caution The following procedure is designed to minimize traffic outages while nodes are removed, but traffic will be lost when you delete and recreate circuits that passed through the removed node.


Step 1 Log into CTC and display the UPSR nodes in network view. Verify the following:

All UPSR spans on the network map are green.

No critical or major alarms (LOF, LOS, ASP, ASL) are displayed on the Alarms tab.

On the Conditions tab, no UPSR switches are active.

At each physical UPSR node, all fibers are securely connected to the appropriate ports.

If trouble is indicated, for example, a critical or major alarm exists, resolve the problem before proceeding.

Step 2 Use the "Switch UPSR Traffic" procedure to initiate a FORCE switch to switch traffic away from the node you are removing. Initiate a FORCE switch on all spans connected to the node you are removing.


Caution Traffic is not protected during a forced protection switch.

Step 3 In the node that will be removed, delete circuits that originate or terminate in that node. (If a circuit has multiple drops, delete only the drops that terminate on the node you are deleting.)

a. Click the Circuits tab.

b. Select the circuit(s) to delete. To select multiple circuits, press the Shift or Ctrl key.

c. Click Delete.

d. Click Yes when prompted.

Step 4 From the node that will be deleted, remove the east and west span fibers. At this point, the node should no longer be a part of the ring.

Step 5 Reconnect the span fibers of the nodes remaining in the ring.

Step 6 Open the Alarms tab of each newly-connected node and verify that the span cards are free of alarms. Resolve any alarms before proceeding.

Step 7 One circuit at a time, delete and recreate each circuit that passed through the deleted node on different STSs.


Note If the removed node was the BITS timing source, select a new node as the BITS source or select another node as the master timing node.


Step 8 Use the "Switch UPSR Traffic" procedure to clear the protection switch.


5.4 Subtending Rings

The ONS 15454 supports up to ten SONET DCCs. Therefore, one ONS 15454 node can terminate and groom any one of the following ring combinations:

5 UPSRs, or

4 UPSRs and 1 BLSR, or

3 UPSRs and 2 BLSRs

Subtending rings from an ONS 15454 reduces the number of nodes and cards required and reduces external shelf-to-shelf cabling. Figure 5-28 shows an ONS 15454 with multiple subtending rings.

Figure 5-28 An ONS 15454 with multiple subtending rings

Figure 5-29 shows a UPSR subtending from a BLSR. In this example, Node 3 is the only node serving both the BLSR and UPSR. OC-N cards in Slots 5 and 12 serve the BLSR, and OC-N cards in Slots 6 and 13 serve the UPSR.

Figure 5-29 A UPSR subtending from a BLSR

Procedure: Subtend a UPSR from a BLSR

This procedure requires an established BLSR and one BLSR node with OC-N cards and fibers to carry the UPSR. The procedure also assumes you can set up a UPSR. (For UPSR setup procedures, see the "Setting Up a UPSR" section.)


Step 1 In the node that will subtend the UPSR (Node 3 in Figure 5-29), install the OC-N cards that will serve as the UPSR trunk cards (Node 3, Slots 6 and 13).

Step 2 Attach fibers from these cards to the UPSR trunk cards on the UPSR nodes. In Figure 5-29, Slot 6 Node 3 connects to Slot 13/Node 5, and Slot 13 connects to Slot 6/Node 6.

Step 3 From the node view, click the Provisioning > Sonet DCC tabs.

Step 4 Click Create.

Step 5 In the Create SDCC Terminations dialog box, click the slot and port that will carry the UPSR.

Step 6 Click OK.

The selected slots/ports are displayed in the SDCC Terminations section.

Step 7 Put the ports that you will use for the UPSR in service:

a. In the node view, double-click UPSR trunk card.

b. Select the Provisioning > Line tabs. Under Status, choose In Service.

c. Click Apply.

d. Repeat steps a - c for the second UPSR trunk card.

Step 8 Follow Steps 1 - 7 for the other nodes you will use for the UPSR.

Step 9 Go to the network view to view the subtending ring.


Procedure: Subtend a BLSR from a UPSR

This procedure requires an established UPSR and one UPSR node with OC-N cards and fibers to connect to the BLSR. The procedure also assumes you can set up a BLSR. (For BLSR setup procedures, see the "Setting Up BLSRs" section.)


Step 1 In the node that will subtend the BLSR (Node 3 in the Figure 5-29 example), install the OC-N cards that will serve as the BLSR trunk cards (in Figure 5-29, Node 3, Slots 6 and 13).

Step 2 Attach fibers from these cards to the BLSR trunk cards on the BLSR nodes. In Figure 5-29, Slot 6/Node 3 connects to Slot 13/Node 5, and Slot 13 connects to Slot 6/Node 6.

Step 3 From the node view, click the Provisioning > Sonet DCC tabs.

Step 4 Click Create.

Step 5 In the Create SDCC Terminations dialog box, click the slot and port that will carry the BLSR.

Step 6 Click OK.

Step 7 The selected slots/ports are displayed under SDCC Terminations.

Step 8 Put the ports that you will use for the BLSR in service:

a. In the node view, double-click the BLSR trunk card.

b. Select the Provisioning > Line tabs. Under Status, choose In Service.

c. Click Apply.

d. Repeat steps a - c for the second BLSR trunk card.

Step 9 Use the "Provision the BLSR" procedure to configure the BLSR.

Step 10 Follow Steps 1- 8 for the other nodes that will be in the BLSR.

Step 11 Go to the network view to see the subtending ring.


The ONS 15454 can support two BLSRs on the same node. This capability allows you to deploy an ONS 15454 in applications requiring SONET DCSs (digital cross connect systems) or multiple SONET ADMs (add/drop multiplexers).

Figure 5-30 shows two BLSRs shared by one ONS 15454. Ring 1 runs on Nodes 1, 2, 3, and 4. Ring 2 runs on Nodes 4, 5, 6, and 7. Two BLSR rings, Ring 1 and Ring 2, are provisioned on Node 4. Ring 1 uses cards in Slots 5 and 12, and Ring 2 uses cards in Slots 6 and 13.


Note Although different node IDs are used for the two BLSRs shown in Figure 5-30, nodes in different BLSRs can use the same node ID.


Figure 5-30 A BLSR subtending from a BLSR

After subtending two BLSRs, you can route circuits from nodes in one ring to nodes in the second ring. For example in Figure 5-30, you can route a circuit from Node 1 to Node 7. The circuit would normally travel from Node 1 to Node 4 to Node 7. If fiber breaks occur, for example between Nodes 1 and 4 and Nodes 4 and 7, traffic is rerouted around each ring: in this example, Nodes 2 and 3 in Ring 1 and Nodes 5 and 6 in Ring 2.

Procedure: Subtend a BLSR from a BLSR

This procedure requires an established BLSR and one BLSR node with OC-N cards and fibers to carry the BLSR. The procedure also assumes you know how to set up a BLSR. For BLSR setup procedures, see the "Setting Up BLSRs" section.


Step 1 In the node that will subtend the BLSR (Node 4 in Figure 5-30), install the OC-N cards that will serve as the BLSR trunk cards (Node 4, Slots 6 and 13).

Step 2 Attach fibers from these cards to the BLSR trunk cards on the BLSR nodes. In Figure 5-30, Node 4/Slot 6 connects to Node 7/Slot 13, and Slot 13 connects to Node 5/Slot 6.

Step 3 From the node view, click the Provisioning > Sonet DCC tabs.

Step 4 Click Create.

Step 5 In the Create SDCC Terminations dialog box, click the slot and port that will carry the BLSR.

Step 6 Click OK.

Step 7 The selected slots/ports are displayed in the SDCC Terminations section.

Step 8 Put the ports that you will use for the BLSR in service:

a. In the node view, double-click the BLSR trunk card.

b. Select the Provisioning > Line tabs. Under Status, choose In Service.

c. Click Apply.

d. Repeat steps a - c for the second BLSR trunk card.

Step 9 To configure the BLSR, use the "Provision the BLSR" procedure. The subtending BLSR must have a ring ID that differs from the ring ID of the first BLSR.

Step 10 Follow Steps 1 - 8 for the other nodes that will be in the subtending BLSR.

Step 11 Display the network view to see the subtending ring.

Figure 5-31 shows an example of two subtending BLSRs.

Figure 5-31 Viewing subtending BLSRs on the network map

Figure 5-32 shows the Ring subtab for Node 5, which is the node that carries the two rings.

Figure 5-32 Configuring two BLSRs on the same node


5.5 Linear ADM Configurations

You can configure ONS 15454s as a line of add/drop multiplexers (ADMs) by configuring one set of OC-N cards as the working path and a second set as the protect path. Unlike rings, linear (point-to-point) ADMs require that the OC-N cards at each node be in 1+1 protection to ensure that a break to the working line is automatically routed to the protect line.

Figure 5-33 shows three ONS 15454s in a linear ADM configuration. Working traffic flows from Slot 6/Node 1 to Slot 6/Node 2, and from Slot 12/Node 2 to Slot 12/Node 3. You create the protect path by placing Slot 6 in 1+1 protection with Slot 5 at Nodes 1 and 2, and Slot 12 in 1+1 protection with Slot 13 at Nodes 2 and 3.

Figure 5-33 A linear (point-to-point) ADM configuration

Procedure: Create a Linear ADM

Complete the following steps for each node that will be included in the linear ADM.


Step 1 Complete the general setup information for the node. For procedures, see the "Setting Up Basic Node Information" section on page 3-2.

Step 2 Set up the network information for the node. For procedures, see the "Setting Up Network Information" section on page 3-2.

Step 3 Set up 1+1 protection for the OC-N cards in the ADM. In Figure 5-33, Slots 6 and 12 are the working ports and Slots 5 and 13 are the protect ports. In this example, you would set up one protection group for Node 1 (Slots 5 and 6), two for Node 2 (Slots 5 and 6, and 12 and 13) and one for Node 3 (Slots 12 and 13). To create protection groups, see the "Creating Protection Groups" section on page 3-9.

Step 4 For OC-N ports connecting ONS 15454s, set the SONET DCC terminations:

a. Log into a linear ADM node and select the Provisioning > Sonet DCC tabs.

b. In the SDCC Terminations section, click Create.

c. On the Create SDCC Terminations dialog box, select the working port. Click OK.


Note Terminating nodes (Nodes 1 and 3 in Figure 5-33) will have one SDCC, and intermediate nodes (Node 2 in Figure 5-33) will have two SDCCs.


Step 5 Use the "Setting Up ONS 15454 Timing" section on page 3-12 to set up the node timing. If a node is using line timing, set the working OC-N card as the timing source.

Step 6 Place the OC-N ports in service:

a. Open an OC-N card that is connected to the linear ADM.

b. On the Provisioning > Line tabs under Status, select In Service.

c. Click Apply.

Repeat Step 6 for each OC-N card connected to the linear ADM.


Procedure: Convert a Linear ADM to UPSR

The following procedures describe how to convert a three-node linear ADM to a UPSR. You will need a SONET test set to monitor traffic while you perform these procedures.


Caution This procedure is service affecting.


Caution Always wear an authorized electrostatic discharge wrist band when removing or installing ONS 15454 cards.


Step 1 Start CTC and log into one of the nodes that you want to convert from linear to ring.

Step 2 Click the Maintenance > Protection tabs ( Figure 5-34).

Figure 5-34 Verifying working slots in a protection group

Step 3 Under Protection Groups, select the 1+1 protection group (that is, the group supporting the 1+1 span cards).

Step 4 Under Selected Group, verify that the working slot/port is shown as "Working/Active." If yes, go to Step 5. If the working slot says "Working/Standby" and the protect slot says "Protect/Active," switch traffic to the working slot:

a. Under Selected Group, select the protect slot, that is, the slot that says "Protect/Active."

a. From the Switch Commands, select Manual.

b. Click Yes on the confirmation dialog box.

c. Under Selected Group, verify that the working slot/port says "Working/Active." If so, continue to Step (d). If not, clear the conditions that prevent the card from carrying working traffic before proceeding.

d. From the Switch Commands, select Clear. A Confirm Clear Operation dialog is displayed.

e. Click Yes on the confirmation dialog box.

Step 5 Repeat Step 4 for each group in the 1+1 Protection Groups list at all nodes that will be converted.

Step 6 For each node, delete the 1+1 OC-N protection group that supports the linear ADM span:


Note Deleting a 1+1 protection group may cause unequipped path (UNEQ-P) alarms to occur.


a. Click the Provisioning > Protection tabs ( Figure 5-35).

b. From the Protection Groups list, choose the 1+1 group you want to delete. Click Delete.

c. Click Yes on the confirmation dialog box.

d. Verify that no traffic disruptions are indicated on the test set. If disruptions occur, do not proceed. Recreate the protection group and isolate the cause of the disruption.

e. Continue deleting 1+1 protection groups while monitoring the existing traffic with the test set.

Figure 5-35 Deleting a protection group

Step 7 Physically remove one of the protect fibers running between the middle and end nodes. For example, in the Figure 5-36, the fiber from Node 2/Slot 13 to Node 3/Slot 13 is removed. The corresponding OC-48 card will go into an LOS condition for that fiber and port.

Figure 5-36 Converting a linear ADM to a UPSR

Step 8 Physically reroute the other protect fiber to connect the two end nodes. In the Figure 5-36 example, the fiber between Node 1/Slot 5 and Node 2/Slot 5 is rerouted to connect Node 1/Slot 5 to Node 3/Slot 13.

If you are leaving the OC-N cards in place, go to Step 13. If you are removing the cards, complete Steps 9 - 12. (In this example, cards in Node 2/Slots 5 and 13 are removed.)

Step 9 In the middle node, place the cards in Slots 5 and 13 out of service:

a. Display the first card in card view and select the Provisioning > Line tabs.

b. Under Status, select Out of Service. Click Apply.

c. Repeat Steps a and b for the second card.

Step 10 Delete the equipment records for the cards:

a. Display the node view. (In card view, click the Up arrow on the toolbar.)

b. Right-click the card you just took out of service (e.g. Slot 5) and select Delete Card. (You can also go to the Inventory tab, select the card, and click Delete.)

c. Click Yes on the confirmation dialog box.

d. Repeat (a) through (c) for the second card (e.g. Slot 13).

Step 11 Save all circuit information.

a. In node view, select the Provisioning > Circuits tab.

b. Record the circuit information using one of the following procedures:

From the File menu, select Print to print the circuits table, or,

From the File menu, select Export to export the circuit data in HTML, CSV (comma separated values), or TSV (tab separated values). Click Ok and save the file in a temporary directory.

See the "Printing and Exporting CTC Data" section on page 2-26 for more information.

Step 12 Remove the OC-N cards that are no longer connected to the end nodes (Slots 5 and 13, in the example).

Step 13 Display one of the end nodes (Node 1 or Node 3 in the example).

Step 14 Click the Provisioning > Sonet DCC tabs.

Step 15 In the SDCC Terminations section, click Create.

Step 16 In the Create SDCC Terminations dialog box, select the slot/port that had been the protect slot in the linear ADM, for example, for Node 1, this would be Slot 5/Port 1 (OC-48).

Step 17 Click OK.

An EOC SDCC alarm will occur until an SDCC termination is created on the adjacent node.

Step 18 Go to the node on the opposite end (Node 3 in the Figure 5-36 example) and repeat Steps 14 - 17.

Step 19 Delete and reenter the circuits one at a time. (See the "Creating Circuits and VT Tunnels" section on page 6-2.)


Note Deleting circuits is traffic affecting.


You can create the circuits automatically or manually. However, circuits must be protected. When they were built in the linear ADM, they were protected by the protect path on Node 1/Slot 5 to Node 2/Slot 5 to Node 3/Slot 13. With the new UPSR, circuits should also be created with protection.

Deleting the first circuit and recreating it to the same card/port should restore the circuit immediately.

Step 20 Monitor your SONET test set to verify that the circuit was deleted and restored.

Step 21 You should also verify that the new circuit path for the clockwise (CW) fiber from Node 1 to Node 3 is working. To do this, switch to network view and move your cursor to the green span between Node 1 and 3.

Although the cursor only shows the first circuit created, do not become alarmed that the other circuits are not present. Verify with the SONET test set that the original circuits and the new circuits are operational. The original circuits were created on the counter clockwise linear path.

Step 22 Go to the network map to view the newly-created ring ( Figure 5-37).

Figure 5-37 A UPSR displayed in network view


Procedure: Convert a Linear ADM to a BLSR

The following procedures describe how to convert a three-node linear ADM to a BLSR. You will need a SONET test set to monitor traffic while you perform these procedures.


Caution This procedure is service affecting.


Caution Always wear an authorized electrostatic discharge wrist band when removing or installing ONS 15454 cards.


Step 1 Start CTC and log into one of the nodes that you want to convert from linear to ring.

Step 2 Click the Maintenance > Protection tabs.

Step 3 Under Protection Groups, select the 1+1 protection group (that is, the group supporting the 1+1 span cards).

Step 4 Under Selected Group, verify that the working slot/port is shown as "Working/Active." If yes, go to Step 5. If the working slot says "Working/Standby" and the protect slot says "Protect/Active," switch traffic to the working slot:

a. Under Selected Group, select the protect slot, that is, the slot that says "Protect/Active."

a. From the Switch Commands, select Manual.

b. Click Yes on the confirmation dialog box.

c. Verify that the working slot is carrying traffic. If it is, continue to Step (d). If not, clear the conditions that prevent the card from carrying working traffic before proceeding.

d. From the Switch Commands, select Clear. A Confirm Clear Operation dialog is displayed.

e. Click Yes on the confirmation dialog box.

Step 5 Repeat Step 4 for each group in the 1+1 Protection Groups list at all nodes that will be converted.

Step 6 For each node, delete the 1+1 OC-N protection group that supports the linear ADM span:

a. Click the Provisioning > Protection tabs.

b. From the Protection Groups list, choose the group you want to delete. Click Delete.

c. Click Yes on the confirmation dialog box.

d. Verify that no traffic disruptions are indicated on the SONET test set. If disruptions occur, do not proceed. Add the protection group and begin troubleshooting procedures to find out the cause of the disruption.


Note Deleting a 1+1 protection group may cause unequipped path (UNEQ-P) alarms to occur.


Step 7 Physically remove one of the protect fibers running between the middle and end nodes. In the Figure 5-38 example, the fiber running from Slot 13/Node 2 to Slot 13/Node 3 is removed. The corresponding end-node trunk card will display an LOS alarm.

Figure 5-38 Converting a linear ADM to a BLSR

Step 8 Physically reroute the other protect fiber so it connects the two end nodes. In the Figure 5-38 example, the fiber between Node 1/Slot 5 and Node 2/Slot 5 is rerouted to connect Node 1/Slot 5 to Node 3/Slot/ 13.

If you are leaving the OC-N cards in place, go to Step 13. If you are removing the cards, complete Steps 9 - 12. (In this example, cards in Node 2/Slots 5 and 13 are removed.)

Step 9 In the middle node, place the cards in Slots 5 and 13 out of service:

a. Display the first card in card view, then select the Provisioning > Line tabs.

b. Under Status, select Out of Service. Click Apply.

c. Repeat Steps a and b for the second card.

Step 10 Delete the equipment records for the cards:

a. From the View menu, choose Node View.

b. Right-click the card you just took out of service (e.g. Slot 5) and select Delete Card. (You can also go to the Inventory tab, select the card, and click Delete.)

c. Click Yes on the confirmation dialog box.

d. Repeat (a) through (c) for the second card (e.g. Slot 13).

Step 11 Save all circuit information:

a. In node view, select the Provisioning > Circuits tab.

b. Record the circuit information using one of the following procedures:

From the File menu, select Print to print the circuits table, or,

From the File menu, select Export to export the circuit data in HTML, CSV (comma separated values), or TSV (tab separated values). Click Ok and save the file in a temporary directory.

See the "Printing and Exporting CTC Data" section on page 2-26 for more information.

Step 12 Remove the OC-N cards that are no longer connected to the end nodes (Slots 5 and 13, in the example).

Step 13 Log into an end node. In node view, click the Provisioning > Sonet DCC tabs.

Step 14 In the SDCC Terminations section, click Create.

Step 15 Highlight the slot that is not already in the SDCC Terminations list (in this example, Port 1 of Slot 5 (OC-48) on Node 1.

Step 16 Click OK. (An EOC SDCC alarm will occur until the DCC is created on the other node; in the example, Node 3/Slot 13.

Step 17 Display the node on the opposite end (Node 3 in Figure 5-38) and repeat Steps 13 - 16.

Step 18 For circuits running on a BLSR protect STS (STSs 7 - 12 for an OC-12 BLSR, STSs 25 - 48 for an OC-48 BLSR), delete and recreate the circuit:

a. Delete the first circuit.

b. Recreate the circuit on STSs 1 - 6 (for an OC-12 BLSR) or 1 - 24 (for an OC-48 BLSR) on the fiber that served as the protect fiber in the linear ADM. During circuit creation, deselect "Route Automatically" and "Fully Protected Path" on the Circuit Creation dialog box so you can manually route the circuit on the appropriate STSs. See the "Create a Unidirectional Circuit with Multiple Drops" procedure on page 6-8 for more information.

c. Repeat Steps (a) and (b) for each circuit residing on a BLSR protect STS.


Note Deleting circuits is traffic affecting.


Step 19 Follow all procedures in the "Setting Up BLSRs" section to configure the BLSR. The ring should have an East/West logical connection. While it may not physically be possible to connect the OC-N cards in an East/West pattern, it is strongly recommended. If the network ring that is already passing traffic does not provide the opportunity to connect fiber in this manner, logical provisioning can be performed to satisfy this requirement.

Be sure to assign the same Ring ID and different node IDs to all nodes in the BLSR. Do not accept the BLSR ring map until all nodes are provisioned.


Note E-W Mismatch alarms will occur until all nodes are provisioned.


Step 20 Display the network map to view the newly-created ring.


5.6 Path-Protected Mesh Networks

In addition to single BLSRs, UPSRs and ADMs, you can extend ONS 15454 traffic protection by creating path-protected mesh networks (PPMNs). PPMNs include multiple ONS 15454 SONET topologies and extend the protection provided by a single UPSR to the meshed architecture of several interconnecting rings. In a PPMN, circuits travel diverse paths through a network of single or multiple meshed rings. When you create circuits, you can have CTC automatically route circuits across the PPMN, or you can manually route them. You can also choose levels of circuit protection. For example, if you choose full protection, CTC creates an alternate route for the circuit in addition to the main route. The second route follows a unique path through the network between the source and destination and sets up a second set of cross-connections.

For example, in Figure 5-39, a circuit is created from Node 3 to Node 9. CTC determines that the shortest route between the two nodes passes through Node 8 and Node 7, shown by the dotted line, and automatically creates cross-connections at Nodes, 3, 8, 7, and 9 to provide the primary circuit path.

If full protection is selected, CTC creates a second unique route between Nodes 3 and 9 which, in this example, passes through Nodes 2, 1, and 11. Cross-connections are automatically created at Nodes, 3, 2, 1, 11, and 9, shown by the dashed line. If a failure occurs on the primary path, traffic switches to the second circuit path. In this example, Node 9 switches from the traffic coming in from Node 7 to the traffic coming in from Node 11 and service resumes. The switch occurs within 50 ms.

Figure 5-39 A path-protected mesh network

PPMN also allows spans of different SONET line rates to be mixed together in "virtual rings." Figure 5-40 shows Nodes 1, 2, 3, and 4 in a standard OC-48 ring. Nodes 5, 6, 7, and 8 link to the backbone ring through OC-12 fiber. The "virtual ring" formed by Nodes 5, 6, 7, and 8 uses both OC-48 and OC-12.

Figure 5-40 A PPMN virtual ring