| 1. |
- Jena, Ajit K., et al.
(författare)
-
Application Layer Tracing for Performance Evaluation
- 2002
-
Konferensbidrag (refereegranskat)abstract
- The paper reports on a set of non-intrusive tools that can be used for the performance evaluation of "classical" Internet applications such as Email, WWW, and FTP. At the application layer, key factors influencing the events are stochastic aspects of user behavior, protocol characteristics and sizes of contents transferred. A multi pronged approach involving application log analysis, direct probe of the WWW pages, and network flow analysis has been used. The measurement infrastructure is presented and diverse software tools for gathering of application layer properties are described in detail. The motivation is to build stochastic models for the key elements of application layer that can be further used to build up an integrated end-to-end performance testbed for conducting traffic engineering experiments.
|
|
| 2. |
- Jena, Ajit K., et al.
(författare)
-
End-User Performance of WWW Services
- 2001
-
Konferensbidrag (refereegranskat)abstract
- The global Internet has seen tremendous growth in terms of nodes and user base as well as of types of applications. One of the most important consequences of this growth is related to an increased complexity of the traffic models experienced in the networks. Each application has a set of unique characteristics in terms of the way it performs its transactions as well as the way transaction processing profile maps onto unique network resource requirements. In order to support Internet applications effectively, it is therefore important to understand and to characterize the application level transactions and also to investigate their scaling properties. Recent advances in high resolution traffic monitoring and analyzing capabilities have enabled us to build up realistic models for the TCP/IP protocol stack with diverse network applications. In this paper we report investigations of classical applications such as FTP, SMTP, and HTTP to evaluate end-to-end performance requirements and accordingly to assess end-user performance like Service Level Agreement (SLA) for WWW. Our results show the presence of a robust correlation structure in the traffic streams that has a fundamental bearing on the user perceived quality of the applications.
|
|
| 3. |
- Jena, Ajit K., et al.
(författare)
-
Modeling and Analysis of HTTP Traffic
- 2000
-
Konferensbidrag (refereegranskat)abstract
- The global Internet has seen tremendous growth in terms of nodes and user base as well as of types of applications. One of the most important consequences of this growth is related to an increased complexity of the traffic experienced in these networks. Each application has a set of unique characteristics in terms of performance characteristics, transactions as well as the way the transaction processing profile maps onto unique network resource requirements. In order to support Internet applications effectively,it is therefore important to understand and to characterize the application level transactions as well as the effect of different TCP/IP control mechanisms on application-level parameters. It is the goal of this paper to model and to evaluate the characteristics of World Wide Web traffic. Results are reported on measuring, modeling and analysis of specific Hyper Text Transfer Protocol traffic collected from different (classes of) sites together with methodologies used for capturing HTTP flows as well as for modeling. The paper concludes with a discussion on the structure of Web pages and a model for the generation of the number of embedded pages in a Web page is suggested.
|
|
| 4. |
- Jena, Ajit K., et al.
(författare)
-
Modeling and Evaluation of Internet Applications
- 2002
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The paper presents a modeling and evaluation study of the characteristics of several "classical" Internet applications (SMTP, HTTP and FTP) in terms of user behavior, nature of contents transferred and application layer protocol exchanges. Results are reported on measuring, modeling and analysis of application layer traces collected, at both the client and the server end, from different environments such as university networks and commercial Frame Relay networks. The methodologies used for capturing traffic flows as well as for modeling are reported. Statistical models have been developed for diverse parameters of applications (e.g., HTTP document sizes, FTP file sizes, and SMTP message sizes), which can be useful for building synthetic workloads for simulation and benchmarking purposes. All three applications possess a session oriented structure. Within each session, a number of transactions are performed. For the above mentioned applications, the number of transactions that may occur during a session has been also modeled.
|
|
| 5. |
- Jena, Ajit K., et al.
(författare)
-
Modeling of Internet Applications
- 2000
-
Konferensbidrag (refereegranskat)abstract
- The global Internet has seen tremendous growth in terms of nodes and user base as well as of types of applications. One of the most important consequences of this growth is related to an increased complexity of the traffic experienced in these networks. Each application has a set of unique characteristics in terms of performance characteristics, transactions as well as the way the transaction processing profile maps onto unique network resource requirements. In order to support Internet applications effectively, it is therefore important to understand and to characterize the application level transactions as well as the effect of different TCP/IP control mechanisms on application-level parameters. It is the goal of this paper to model and to evaluate the characteristics of World Wide Web traffic. Results are reported on measuring, modeling and analysis of specific Hyper Text Transfer Protocol traffic collected from different (classes of) sites together with methodologies used for capturing HTTP flows as well as for modeling. The paper concludes with a discussion on the structure of Web pages and a model for the generation of the number of embedded pages in a Web page is suggested.
|
|
| 6. |
- Jena, Ajit K., et al.
(författare)
-
Resource Engineering for Internet Applications
- 2002
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The focus of the paper is on resource engineering for supporting Service Level Agreements (SLAs) in IP networks. We review some of the recent developments in Internet service architecture and protocol developments as well as some of the most important challenges still to be considered. An important performance metrics that must be considered in developing the new Internet is regarding the delay and the delay variation/jitter. Connected with this, a case-study is reported on end-to-end delay performance in a best-effort Internet. Performance issues of Short Range Dependence (SRD) and Long Range Dependence (LRD) traffic under different resource control regimes are compared. The results show that a major portion of the end-to-end delay comes from the queueing delay at the WAN ingress point, which is due to the significant bandwidth differences that may exist between LAN and WAN link layers. The results also highlight the role TCP window size and Frame Relay Permanent Virtual Channel (FR PVC) control mechanisms play in the provision of delay performance for Internet services.
|
|
| 7. |
- Jena, Ajit K., et al.
(författare)
-
Traffic Engineering for Internet Applications
- 2001
-
Konferensbidrag (refereegranskat)abstract
- The focus of the paper is on resource engineering for supporting Service Level Agreements (SLAs) in IP networks. SLA at both link level and application level are considered. Using an object-oriented simulation model a case study is presented for client-server interactions generated by mixed traffic conditions in a Frame Relay (FR) WAN. Performance issues of Short Range Dependence (SRD) and Long Range Dependence (LRD) traffic under different resource control regimes are compared. The results show that major portion of the end-to-end delay comes from the queueing delay at the WAN ingress points, which is due to the significant bandwidth differences that may exist between LAN and WAN link layers. The results also highlight the role TCP window size and FR PVC control mechanisms play in the provision of delay performance for Internet services.
|
|
| 8. |
- Popescu, Adrian, et al.
(författare)
-
Modeling and Evaluation of Internet Applications
- 2003
-
Konferensbidrag (refereegranskat)abstract
- The paper presents a modeling and evaluation study of the characteristics of SMTP and HTTP applications in terms of user behavior, nature of contents transferred and application layer protocol exchanges. Results are reported on measuring, modeling and analysis of application level traces collected, at client and server ends, from different environments such as university networks and commercial Frame Relay networks. The methodologies used for capturing traffic flows and for modeling are reported. Statistical models have been developed for diverse parameters of applications, which can be useful for building synthetic workloads for simulation and benchmarking purposes. Both applications possess a session oriented structure. Within each session, a number of transactions may occur, and this number has been modeled as well.
|
|
| 9. |
- Popescu, Adrian, et al.
(författare)
-
Resource Engineering for Internet Applications
- 2003
-
Konferensbidrag (refereegranskat)abstract
- The focus of the paper is on resource engineering for supporting Service Level Agreements (SLAs) in IP networks. We review some of the recent developments in Internet service architecture and protocol developments as well as some of the most important challenges still to be considered. An important performance metrics that must be considered in developing the new Internet is regarding the delay and the delay variation/jitter. Connected with this, a case-study is reported on end-to-end delay performane in a simple model for best-effort Internet where the bandwidth is not a commodity. The case-study is based on a client-server simulation model. The client and the server nodes are running applications like HTTP and SMTP, and they are placed in two sites separated by an Internet cloud. Performance issues of Short Range Dependence (SRD) and Long Range Dependence (LRD) traffic under different resource control regimes are compared. The results highlight the importance of the queueing delay at the WAN ingress point, which is due to the significant bandwidth differences that may exist, in this case, between the LAN and WAN link layers. The results also highlight the role TCP window size and Frame Relay Permanent Virtual Channel (FR PVC) control mechanisms play in the provision of delay performance for Internet services.
|
|
