Chapter 12 Configuring Quality of Service on the ML-Series Card

Understanding QoS

Figure 12-1 IP Precedence and DSCP

Bits

0

1

2

3

4

5

6

7

Bits

0

1

2

3

4

5

6

7

DS-Field

DSCP

CU

Precedence

Type of Service

MBZ

Class Selector

CodepointsCurrently

Unused

Differentiated Services Code Point

RFC 1122

DTR-Bits

Must

 

be

RFC 1349

zero

 

AFC 2474

Bits (0-2): IP-Precedence Defined 111 (Network Control)

110 (Internetwork Control)

101 (CRITIC/ECP)

100 (Flash Override)

011 (Flash)

101 (Immediate)

001 (Priority)

000 (Routine)

Bits (3-6): Type of Service Defined 0000 (all normal)

1000 (minimize delay)

0100 (maximize throughput)

0010 (maximize reliability)

0001 (minimize monetary cost)

96499

Ethernet CoS

Ethernet CoS refers to three bits within a four byte IEEE 802.1Q (VLAN) header used to indicate the priority of the Ethernet frame as it passes through a switched network. The CoS bits in the IEEE 802.1Q header are commonly referred to as the IEEE 802.1p bits. There are three CoS bits that provide eight classes, matching the number delivered by IP precedence. In many real-world networks, a packet might traverse both Layer 2 and Layer 3 domains. To maintain QoS across the network, the IP ToS can be mapped to the Ethernet CoS and vice versa, for example, in linear or one-to-one mapping, because each mechanism supports eight classes. Similarly, a set of DSCP values (64 classes) can be mapped into each of the eight individual Ethernet CoS values. Figure 12-2is an IEEE 802.1Q Ethernet frame, which consists of a 2-byte Ethertype and a 2-byte tag (IEEE 802.1Q Tag) on the Ethernet protocol header.

Figure 12-2 Ethernet Frame and the CoS Bit (IEEE 802.1p)

IEEE 802.1p

(3 bits)

CoS

CFI

 

 

 

 

VLAN ID

IEEE 802.1Q Tag

6Destination Address

6Source Address

2 Type=8100

2Tag Control Information

2Type/Length

42~1500

PAD

 

MAC DATA

 

 

4

FCS

96496

Cisco ONS 15310-CL, ONS 15310-MA, and ONS 15310-MA SDH Ethernet Card Software Feature and Configuration Guide, R9.1 and R9.2

 

78-19415-01

12-3

 

 

 

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Cisco Systems ONS 15310-CL, Cisco ONS 15310-MA manual Ethernet CoS, 12-3
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ONS 15310-CL, ONS 15310-MA, Cisco ONS 15310-MA specifications

Cisco Systems has long been a leader in networking and telecommunications technology, and among its impressive lineup of products, the Cisco ONS 15310 series stands out as an essential solution for optical networking. This series includes models such as the ONS 15310-MA, ONS 15310-CL, and ONS 15310-CA, each designed to meet the diverse needs of service providers and enterprises seeking to enhance their optical transport networks.

The Cisco ONS 15310-MA is an advanced multi-service platform designed for metropolitan area networks. It facilitates the seamless transport of data, voice, and video over optical networks. One of its main features is its ability to support a variety of interfaces, including Ethernet, SONET/SDH, and Wavelength Division Multiplexing (WDM), allowing users to integrate multiple services into a single platform. Additionally, the ONS 15310-MA supports advanced traffic management and Quality of Service (QoS) features to prioritize critical applications and ensure consistent performance.

The ONS 15310-CL variant is tailored for more specific applications, providing enhanced capabilities aimed at delivering carrier-grade services. It features a robust architecture that accommodates high-capacity traffic without compromising reliability. This model emphasizes low power consumption and a compact design, making it suitable for deployment in space-constrained environments. The ONS 15310-CL also supports a wide range of optical interfaces, making it highly flexible for various network configurations.

In terms of technologies, the Cisco ONS 15310 series leverages Optical Transport Network (OTN) capabilities, providing high efficiency and greater bandwidth utilization. OTN technology enables efficient error correction and adds resilience to the network through its built-in protection mechanisms. Furthermore, the series supports seamless integration with existing IP/MPLS networks, creating a cohesive infrastructure as organizations evolve their networking requirements.

One of the defining characteristics of the ONS 15310 series is its focus on scalability. Network operators can start with a modest deployment and gradually expand capacity as demand grows. This adaptability is complemented by Cisco's comprehensive management and monitoring tools, providing operators with real-time insights into network performance and facilitating proactive management.

In conclusion, the Cisco ONS 15310-MA and ONS 15310-CL models represent sophisticated solutions for modern optical networks. With their versatile features, advanced technologies, and robust design, they empower service providers and enterprises to build resilient, high-capacity networks that meet the demands of today’s data-driven world.
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