Testing and modeling Ethernet switches and networks for use in ATLAS high-level triggers

Author

Dobinson, R.W. ; Haas, S. ; Korcyl, K. ; LeVine, M.J. ; Lokier, J. ; Martin, B. ; Meirosu, C. ; Saka, F. ; Vella, K.

Author_Institution

CERN, Geneva, Switzerland

Volume

48

Issue

3

fYear

2001

fDate

6/1/2001 12:00:00 AM

Firstpage

607

Lastpage

612

Abstract

The ATLAS second-level trigger will use a multilayered local-area network to transfer 5-Gbyte/s detector data from ~1500 buffers to a few hundred processors. A model of the network has been constructed to evaluate its performance. A key component of the network model is a model of an individual switch, reproducing the behavior measured in real devices. A small number of measurable parameters are used to model a variety of commercial Ethernet switches. Using parameters measured on real devices. The impact on the overall network performance is modeled. In the ATLAS context, both 100-Mbit and gigabit Ethernet links are required. A system is described that is capable of characterizing the behavior of commercial switches with the required number of nodes under traffic conditions resembling those to be encountered in the ATLAS experiment. Fast Ethernet traffic is provided by a high-density custom-built tester based on field-programmable gate arrays, programmed in Handel-C and VHDL, while the gigabit Ethernet traffic is generated using Alteon NICs with custom firmware. The system is currently being deployed with 32 100-Mbit ports and 16 gigabit ports, and will be expanded to ~256 nodes of 100 Mbit and ~50 GBE nodes

Keywords

field programmable gate arrays; high energy physics instrumentation computing; local area networks; switches; 5 Gbyte/s; ATLAS; Alteon NICs; Ethernet switches; Handel-C; VHDL; field-programmable gate arrays; high-level triggers; multilayered local-area network; networks; second-level trigger; Detectors; Ethernet networks; Field programmable gate arrays; Intelligent networks; Local area networks; Microprogramming; Switches; Telecommunication traffic; Testing; Traffic control;

fLanguage

English

Journal_Title

Nuclear Science, IEEE Transactions on

Publisher

ieee

ISSN

0018-9499

Type

jour

DOI

10.1109/23.940127

Filename

940127