How Does MPLS QoS Work?

1. How Does MPLS QoS Work?

2. BE Criteria AF Criteria EF Criteria Global Crossing VPN Service – CoS • CoS configuration and capabilities differ for traffic entering the VPN to traffic leaving the VPN • Inbound • Classification of traffic • Maps traffic into the three backbone Class (EF - Premium, AF - Enhanced, BE - Basic) via • Customer Classification using IP Precedence or DSCP code point value in the IP header • Assumes the customer is already using Differentiated Services in their network • Provider Classification using a combination of the following IP header values. • Source Address • Destination Address • Source Port • Destination Port • Protocol • A class classifier will only be provisioned if the customer has subscribed to the class Traffic from CPE • Any Combination of class classifiers are supported • EF, AF, BE • EF, AF • EF, BE • EF • AF, BE • AF • BE The final (last) classifier does not need any criteria as it will match all remaining unclassified traffic

3. BE Criteria AF Criteria BE Policer EF Criteria AF Policer EF Policer Global Crossing VPN Service – CoS • CoS configuration and capabilities differ for traffic entering the VPN to traffic leaving the VPN • Inbound • Policing of Traffic • Controls the volume of traffic in each class to a subscribed rate • Known as the Class Subscription Rate or CSR • Sum of the CSR rates must equal the port speed • The class and traffic subscribed to by a customer will dictate if a class policer is configured or not • Allows Global Crossing to control traffic according to 3 traffic models • Usage • Excess EF is Dropped; Excess AF is Dropped; Excess BE is Dropped EF CSR Usage E1 AF CSR Traffic from CPE Discard BE CSR Discard Discard

4. BE Criteria AF Criteria EF Criteria AF Policer EF Policer Global Crossing VPN Service – CoS • CoS configuration and capabilities differ for traffic entering the VPN to traffic leaving the VPN • Inbound • Policing of Traffic • Controls the volume of traffic in each class to a subscribed rate • Known as the Class Subscription Rate or CSR • Sum of the CSR rates must equal the port speed • The class and traffic subscribed to by a customer will dictate if a class policer is configured or not • Allows Global Crossing to control traffic according to 3 traffic models • Usage • Excess EF is Dropped; Excess AF is Dropped; Excess BE is Dropped • Flat Rate • Excess EF is Dropped; Excess AF is marked BE; BE can use Full Port EF CSR Flat Rate E1 AF CSR Traffic from CPE Discard By Full Port we mean that we can receive a full ports worth of traffic for example 2Mb on an E1 for the given class at any instantaneous point in time, as long as no other class traffic is being received at that same point in time. BE CSR Sum of CSR’s = Port Speed

5. BE Criteria AF Criteria EF Criteria EF Policer Global Crossing VPN Service – CoS • CoS configuration and capabilities differ for traffic entering the VPN to traffic leaving the VPN • Inbound • Policing of Traffic • Controls the volume of traffic in each class to a subscribed rate • Known as the Class Subscription Rate or CSR • Sum of the CSR rates must equal the port speed • The class and traffic subscribed to by a customer will dictate if a class policer is configured or not • Allows Global Crossing to control traffic according to 3 traffic models • Usage • Excess EF is Dropped; Excess AF is Dropped; Excess BE is Dropped • Flat Rate • Excess EF is Dropped; Excess AF is marked BE; BE can use Full Port • Usage with Burst • Excess EF is Dropped; AF can use Full Port; BE can use Full Port EF CSR Usage with Burst E1 AF CSR Traffic from CPE Discard By Full Port we mean that we can receive a full ports worth of traffic for example 2Mb on an E1 for the given class at any instantaneous point in time, as long as no other class traffic is being received at that same point in time. BE CSR Sum of CSR’s = Port Speed

6. BE BE BE AF EF BE Criteria AF Criteria EF Criteria AF Policer EF Policer Global Crossing VPN Service – CoS • CoS configuration and capabilities differ for traffic entering the VPN to traffic leaving the VPN • Inbound • Mark the MPLS Header with relevant CoS value • Allows the entire network to treat the packet based on the Backbone class specified in the classification • Provides Diff Serv transparency. • By not modifying the IP Precedence value the customers marking stay intact Send to Core with MPLS EXP = Or Send to egress Customer interface Traffic from CPE Discard

7. Applications – Today and Tomorrow • Intranets – for company communications – LAN extension • Remote access solution for mobile workforce and remote locations • Extranets – for customers, partners, suppliers & communities of interest • Connections to Global Crossing Financial Extranet (content) • Analyst firm – customers download reports, video conferencing & streaming video • Hosted applications • Convergence of applications: voice, video, Internet and corporate data • VoIP • IP Videoconferencing • L2 Virtual Private Lines (VPLs) for legacy protocol transport (X.25, FR/ATM) • Business continuity • Redundant back-up with usage based-billing . . . • . . . also carries your extra traffic

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