Log in
|
How to Buy
|
Contact Us
|
United States (Change)

## Choose Country

### North America

- United States

### Europe

- Deutschland - Germany
- España - Spain
- France
- Italia - Italy
- Россия - Russia
- United Kingdom

### Asia Pacific

- Asean Region (Vietnam, Indonesia, Singapore, Malaysia)
- Australia
- 中国 - China
- India
- 日本 - Japan
- 대한민국 - Korea
- 台灣 - Taiwan

Remember my choice

# Technical Documentation

Download Software
Research a Problem
Case Management
Contract & Product Management
Technical Documentation
Documentation Archive
Report Documentation Bug
Enterprise MIBs
File Format Help
Glossary
Portable Libraries
End-of-Life Products
Contact Support
Guidelines and Policies
Security Resources
Feedback

## Documentation Search

Advanced Search | Search Tips

## Related Documentation

- Configuring Bundle Failover Between CTP Devices at Both the Local and Remote Sites (CTP Menu)
- Configuring Bundle Failover Between CTP Devices at Both the Local and Remote Sites (CTPView)

# Bundle Failover Between CTP Devices at Both the Local and Remote Site Overview

You can use Y cables at both the local and remote sites to provide a redundant path for bundles. As shown in Figure 1, you use a Y cable to connect two CTP devices to the customer equipment (CE) at both sites. You then create a primary bundle between one pair of CTP devices, and you create a backup bundle between a second pair of CTP devices.

Figure 1: Y-Cable Redundancy at Both the Local and Remote Sites

## How Bundle Failover Between CTP Devices at Both the Local and Remote Sites Works

Under normal conditions, both the primary and backup bundles are in the running state and are consuming bandwidth. Under these conditions, the primary bundle is carrying the data between the CEs.

If the primary bundle goes down or is no longer in the running state, the CTP devices switch over to the backup bundle, and the backup bundle carries the data. The time that it takes for the switchover to occur depends on the bundle configuration. The switchover time for a typical 1 MHz circuit is less than one second.

When the primary bundle returns to the running state, the CTP devices switch back to the primary bundle, and the primary bundle begins carrying data.

## Requirements for Y-Cable Redundancy

Keep the following in mind when you use Y-cable redundancy:

- Y-cable redundancy is supported only on serial interfaces. The serial interface cannot have a T1/E1 daughter card installed.
- This feature requires a special Y cable. The Y cable provides control leads between the two CTP devices in addition to the standard signal, clock, and data leads connected to the attached device. There is one Y cable for CTP2000 devices and another Y cable for CTP150 devices. Therefore, you must use the same platform type at each site.
- The Y cable is short to maintain signal quality. The two CTP devices connected to the Y cable must be in close proximity to each other.
- To run diagnostics on a nonactive bundle attached to a Y cable without introducing data errors on the active bundle, Y-cable redundancy must be configured, and you cannot have a daughter card installed.

## Clocking Supported with Y-Cable Redundancy

Y-cable redundancy is supported with the following clock configurations:

- Configured rate without external TX clock (TT).
- Configured rate with external TX clock (TT).
- All clocked with external TX clock (TT).
- Adaptive clocking with internal clock.
- Adaptive clocking with external TX clock (TT).

## Related Documentation

- Configuring Bundle Failover Between CTP Devices at Both the Local and Remote Sites (CTP Menu)
- Configuring Bundle Failover Between CTP Devices at Both the Local and Remote Sites (CTPView)

#### Published: 2010-10-26

﻿
Site Map / RSS Feeds / Careers / Accessibility / Feedback / Privacy & Policy / Legal Notices
Copyright© 1999-2011 Juniper Networks, Inc. All rights reserved.
Help
|
My Account
|
Log Out