Chapter 7 Circuits and Tunnels

Virtual Concatenated Circuits

A VCAT circuit is locked-PARTIAL when In Group member states are mixed and not all member states are unlocked.

7.7.2VCAT Member Routing

The automatic and manual routing selection applies to the entire VCAT circuit, that is, all members are manually or automatically routed. Bidirectional VCAT circuits are symmetric, which means that the same number of members travel in each direction. With automatic routing, you can specify the constraints for individual members; with manual routing, you can select different spans for different members.

Two types of automatic and manual routing are available for VCAT members on CE-100T-8, CE-MR-6, and ML-100T-8 cards: common fiber routing and split fiber routing. In common fiber routing, all VCAT members travel on the same fibers, which eliminates delay between members. Three protection options are available for common fiber routing: Fully Protected, PCA, and Unprotected. Split fiber routing allows the individual members to be routed on different fibers or each member to have different routing constraints. This mode offers the greatest bandwidth efficiency and also the possibility of differential delay, which is handled by the buffers on the terminating cards or ports. Three protection options are available for split fiber routing: Fully Protected, Unprotected, and DRI. In both common fiber and split fiber routing, each member can use a different protection scheme; however, for common fiber routing, CTC checks the combination to make sure that a valid route exists. If it does not, the user must modify the protection type.

In both common fiber and split fiber routing, intermediate nodes treat the VCAT members as normal circuits that are independently routed and protected by the SDH network. At the terminating nodes, these member circuits are multiplexed into a contiguous stream of data. Figure 7-3shows an example of common fiber routing.

Figure 7-3

CE-100T-8

VCAT Common Fiber Routing

 

 

 

VCAT

Member 1

VC3

VC3

Member 1

VCAT

VCG-1

VCG-1

Function

STS-2

STS-2

Function

Member 2

Member 2

 

 

 

 

 

 

 

 

 

Intermediate

 

 

 

 

 

NE

 

 

VCAT

Member 1

STS-3

STS-3

Member 1

VCAT

VCG-2

VCG-2

Function

STS-4

STS-4

Function

Member 2

Member 2

 

 

 

 

 

 

CE-100T-8

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Cisco Systems 15310-MA manual Vcat Member Routing, Vcat Common Fiber Routing

15310-MA specifications

Cisco Systems has established itself as a leader in the networking domain, offering a wide array of solutions to meet the needs of modern businesses. Among its impressive product lineup are the Cisco 15310-CL and 15310-MA routers, designed to provide advanced network performance and reliability.

The Cisco 15310-CL is a versatile platform that primarily serves as a carrier-class router aimed at supporting high-speed data and voice services. It is built to handle the demands of large enterprises and service providers, offering a robust design that ensures maximum uptime and performance. One of its standout features is its modular architecture, which enables users to customize their configurations based on specific application needs. This scalability allows for future expansion without the need for a complete hardware overhaul.

Key technologies integrated into the Cisco 15310-CL include high-density Ethernet interfaces and a comprehensive suite of Layer 2 and Layer 3 protocol support. The device is capable of supporting multiple types of connections, including TDM, ATM, and Ethernet. This flexibility makes it an ideal choice for organizations that require seamless migration between various service types. Moreover, with features such as MPLS (Multiprotocol Label Switching) support and advanced Quality of Service (QoS) mechanisms, the router ensures that critical applications receive the necessary bandwidth and low latency required for optimal performance.

In contrast, the Cisco 15310-MA focuses on access solutions, providing a cost-effective entry point for businesses looking to enhance their network capabilities. It is well-suited for smaller offices or branch locations that need reliable connectivity without the expense and complexity associated with larger systems. The device supports a range of access methods and provides essential features like firewall capabilities, VPN support, and comprehensive security measures to protect sensitive data.

Both models benefit from Cisco's commitment to security and manageability, offering features like enhanced encryption protocols and user authentication mechanisms that help safeguard networks against threats. Additionally, they can be managed through Cisco’s intuitive software tools, simplifying configuration and monitoring tasks for IT administrators.

The Cisco 15310-CL and 15310-MA are ideal solutions for businesses seeking to enhance their network infrastructure, ensuring firms can keep pace with evolving technology demands while maintaining a focus on security and performance. Their combination of advanced features, modular capabilities, and robust support makes them valuable assets in the networking landscape.