Specifications

Chapter 2

Network Performance

Measurements Systems

Network testers are devices that can perform measurements of various network parameters.

Usually they are deployed in key points of a network and they work in a distributed fashion.

They perform measurements by injecting traﬃc into one end of the network and capturing

it at the other e nd. Using special data embedded in the traﬃc streams, they are able to

determine one-way latencies, packet loss, jitter or throughput. There are testers that can do

Quality of Service measurements for Voice over IP, or that can emulate certain applications

to see how they behave over a certain network.

We are interested in a system that can perform accurate measurements over the Internet.

The system should be very ﬂexible and the user should be able to extend it if new func-

tionality is needed. A lso a high performance system is needed to analyze networks running

at Gigabit speeds.

2.1 Network testers

2.1.1 IXIA IxCore

The IxCore is a network performance monitoring system. It is a distributed system consist-

ing of collocated measuring devices called Ixia 100s, which are time synchronized across the

globe using the Global Positioning System (GPS) or the CDMA cellular system. IxCore

includes centralized, web-based reporting and management and provides real-time monitor-

ing of critical network performance metrics such as one-way latency, packet loss and jitter.

The accuracy of latency measurements is at the order of microsecond. The system provides

historical reports and an SQL database with the measurements.

2.1.2 Brix 2500 Veriﬁer

The Brix System consists of a family of purpose-built hardware appliances: including the

Brix 100 Veriﬁer, Brix 1000 Veriﬁer, and Brix 2500 Veriﬁer – that are deployed pervasively

throughout a network and are tightly coupled with a carrier-class , central site software