ITU-T G.1050/TIA-921 IP Network Model Overview

ITU-T G.1050/TIA-921 IP Network Model Overview April 2006 VQEG Jack Douglass jack.douglass@spirentcom.com Spirent Communications

G.1050/TIA-921 Overview • Sources of network impairments • Network models including expected values for • Latency • Jitter • Packet loss • Out of sequence packets • Delay

Network Architecture Types of Access Links QoS controlled Edge Routing MTU Size Packet Loss (Frame Loss) Out of order packets One Way Delay (Latency) Variable Delays (Jitter) Background Traffic (Occupancy, Congestion, Network Load) Route Flapping Signaling protocol mismatches Network faults Link Failures Network Impairments and Parameters that Affect Video Quality

1000BaseX 100BaseT Switch 100BaseT Hub 10BaseT WLAN (~4Mbps) ----------------- Occupancy level Packet loss 64kbps 128kbps 256kbps 384kbps 512kbps 768kbps T1/E1 T3/E3 ADSL Cable Fiber ---------------- Occupancy level Qos Edge Router ITU-T G.1050 and TIA-921 IP Network Model Core IP Network LAN A LAN B DUT B Local Access A Local Access B DUT A Route flapping Link Failures One-way delay Jitter Packet loss Packet Reorder 64kbps 128kbps 256kbps 384kbps 512kbps 768kbps T1/E1 T3/E3 ADSL Cable Fiber ---------------- Occupancy level Qos Edge Router 1000BaseX 100BaseT Switch 100BaseT Hub 10BaseT WLAN (~4Mbps) ----------------- Occupancy level Packet loss

ITU-T G.1050 and TIA-921 Test Profiles ITU-T Recommendation Y.1541 uses a similar approach, but there is not a one-to-one mapping.

ITU-T G.1050 and TIA-921 Test Profiles based on ITU-T Y1541 Different test profiles for different Service Level Agreements (SLAs) • Profile A – Well-Managed Network Impairment Ranges • Y.1541 QoS Level – suitable for high quality video and VoIP • Most Service Providers will be supporting this SLA for IPTV

ITU-T G.1050 and TIA-921 Test Profiles based on ITU-T Y1541 Different test profiles for different Service Level Agreements (SLAs) • Profile B – Partially-Managed Network Impairment Ranges • Y.1541 QoS Level – suitable for Lower quality video and VoIP

ITU-T G.1050 and TIA-921 Test Profiles based on ITU-T Y1541 Different test profiles for different Service Level Agreements (SLAs) • Profile C – Un-Managed Network Impairment Ranges • Y.1541 QoS Level – Internet little or no guarantees

Table 10: Impairment Severity Combinations ITU-T G.1050 and TIA-921 8 Impairment Severity Combinations Table 10: Impairment Severity Combinations

ITU-T G.1050 and TIA-921 LAN and Access Rates Home Rates Table 5: LAN Rates for Home Locations Table 7: Access Rates for Home Locations Business Rates Table 6: LAN Rates for Business Locations Table 8: Access Rates for Business Locations LAN and Access Rates (New Revision of Standard/Recomendation) will change as network conditions change 133 LAN/Access Rate Combinations

Impairment Characteristics Good Bad Route Flap Link Failure Severe 1064 Impairment Combinatoins

ITU-T G.1050 and TIA-921 Example of Network Model Coverage (NMC) Curve Video Quality may also be plotted OR

Analyze Assure Accelerate

ITU-T G.1050/TIA-921 IP Network Model Overview