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1

Obsługa ruchu IP QoS w domenie FAN

Kaczmarek S., Landowski M.

Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne

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2008

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T. 15

25-30

PL

W artykule przedstawiono rezultaty przeprowadzonych badań symulacyjnych obsługi ruchu IP z gwarancją klas QoS w domenie FAN. Koncepcja Flow Aware Networking (FAN) to propozycja w miarę prostego sposobu zapewnienia jakości QoS w sieciach IP. Na potrzeby badań, zaproponowano algorytm obsługi ruchu oraz model symulacyjny, który zaimplementowano w środowisku symulatora ns2. Przeprowadzone badania dostarczyły wielu wyników, które umożliwiły określenie cech koncepcji FAN. Prostota koncepcji okupiona jest znacznymi trudnościami w doborze parametrów dla właściwego działania elementów funkcjonalnych tej koncepcji.

EN

In this article we present how IP QoS traffic was serviced in FAN domain according to proposed FAN traffic con-trol algorithm and FAN node model. FAN conception of traffic control is a new approach to guarantee Quality of Service and was proposed recently as an alternative QoS architecture for the Internet. The innovation of FAN is that the same Quality of Service can be provided on flow level, as it is possible to provide on packet level where 'flow' refers to the set of packets with an interpacket interval related to an in stance of same application observed at a given point in the network. Conducted in ns2 simulation research has shown that our traffic control algorithm implemented in FAN Admission Control leads to sufficient end_to_end QoS guarantees in case of proper selection FAN node configuration parameters. The selection has strong impact on guaranteed QoS, so more research in this field is required. On the end of the article we present all observations and conclusions on traffic servicing in FAN domain.

2

Mechanizmy wspomagające gwarantowanie jakości usług świadczonych w heterogenicznych sieciach IPv6 z ograniczeniami przepustowości

Krygier J., Jarmakiewicz J.

Elektronika : konstrukcje, technologie, zastosowania

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2006

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Vol. 47, nr 9

34-41

PL

Zaproponowano mechanizmy pozwalające na gwarantowanie jakości usług fonicznych przesyłanych w sieciach z protokołem IPv6, w których występują łącza z dużymi ograniczeniami przepustowości. Należą do nich mechanizmy: redukcji nagłówków, segmentacji i multipleksacji pakietów, przyjmowania zgłoszeń strumieni fonicznych, obsługi priorytetów oraz emulacji wiadomości kontrolnych. Zastosowanie standardowych mechanizmów do dyferencji jakości usług na brzegach takich łączy nie daje efektu, gdyż opracowane były z myślą o sieciach szerokopasmowych. Wyniki wskazują na znaczą efektywność ich zastosowania w sieciach o przepustowości poniżej 64 kb/s.

EN

The paper covers the proposals for solving a problem of quality of service provision in IPv6-based heterogeneous networks. The discussion is focused especially on narrowband elements of the network. These elements are mostly access subnetworks with radio interfaces. Additionally, the device supports simultaneous transmission of the real and non-real time traffic without decreasing the real time data quality. Following mechanisms are proposed and described: header reduction, packets segmentation, datagrams multiplexing, call admission control, real-time streams priority handling and control packets emulation. These mechanisms were implemented using Linux and tested in the prepared testbed.

3

Methods for evaluation packet delay distribution of flows using Expedited Forwarding PHB

Kaczmarek S., Narloch M.

Journal of Telecommunications and Information Technology

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2004

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nr 2

29-37

EN

The paper regards problem of providing statistical performance guarantees for real-time flows using Expedited Forwarding Per Hop Behavior (EF PHB) in IP Differentiated Services networks. Statistical approach to EF flows performance guarantees, based on calculation of probability that end-to-end packet delay is larger than certain value, allows larger network utilization than previously proposed deterministic approach. In the paper different methods of packet delay distribution evaluation are presented and compared. Considered cases comprise evaluation of delay distribution models for the core network and evaluation of end-to-end packet delay in the network consisted of edge node and chain of core nodes. Results obtained with aid of analytical models are compared with simulation results.

4

A comparison of ATM and IP QoS network capabilities for handling LAN traffic with QoS differentiation

Bęben A., Burakowski W., Pyda P.

Journal of Telecommunications and Information Technology

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2003

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nr 4

25-31

EN

Now, a network operator must choose between two packet switched technologies for providing QoS in WAN networks, which are ATM and IP QoS [3, 4, 9]. As ATM has reached the maturity with capabilities for offering a number of different network services (i.e. CBR, VBR, ABR, UBR, GFR), the IP QoS with network services like expedited forwarding, assured forwarding, etc. is still at developing phase but never-theless is commonly regarded as capable to guarantee in near future similar QoS level as ATM. This paper tries to compare the efficiency of the mentioned technologies (in case of IP QoS network the AQUILA network concept [1, 2] is investigated) for handling traffic generated by LANs with QoS differentiation. This is extremely required since the applications running in LAN differ in QoS requirements and emitted traffic profiles (streaming, elastic). Therefore, a classification process of outgoing LAN traffic into predefined sub-streams should be performed at the entry point to WAN network (edge ATM switch or IP router). Furthermore, particular sub-streams are submitted to adequate WAN network service, available in ATM or IP QoS. The paper presents the experimental results, measured in the test bed, corresponding to QoS level and QoS differentiation provided by ATM and IP QoS core.For this purpose, a set of representative applications currently available to a LAN user was selected demanding from the core different QoS level. They correspond to streaming applications like VoIP with QoS objectives represented mainly by packet delay characteristics and elastic applications controlled by TCP protocol with minimum guaranteed through-put/goodput as target.

5

AQUILA network architecture: first trial experiments

Bąk A., Bęben A., Burakowski W., Dąbrowski M., Fudała M., Tarasiuk H., Kopertowski Z.

Journal of Telecommunications and Information Technology

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2002

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nr 2

3-13

EN

The paper presents trial experiments with IP QoS network services (NS) defined and implemented in the AQUILA pilot installation. The AQUILA NSs (premium CBR, premium VBR, premium multimedia and premium mission critical) provide a framework for supporting a variety of applications generating both streaming and elastic traffic. The measurement experiments confirm that AQUILA architecture differentiates the QoS offered to these NSs. The presented numerical results were obtained in the test network installed in the Polish Telecom (Warsaw) consisting of 8 CISCO routers.