Mikel Izal

Publications (57) View all

• Source

  Available from: Felix Espina

  Conference Proceeding: Ingress traffic classification versus aggregation in video over OBS networks

  M Izal, F Espina, D Morató, E Magaña
  [show abstract] [hide abstract]
  ABSTRACT: Optical Burst Switched (OBS) networks may become a backbone technology for video-on-demand providers. This work addresses the problem of dimen-sioning the access link of an ingress node to the optical core network in a video over OBS scenario. A video-on-demand provider using an OBS transport network will have to deliver traffic to a set of egress destinations. A large part of this traffic would be composed of video streaming traffic. However, in a real network there would be also a fraction of non video traffic related to non video services. This work studies the decision whether it is better to gather all traffic to the same destination in a joint burst assembler or separate video and general data traffic on different burs assemblers. The later may increase burst blocking probability but also allow for better tuning of OBS parameters that help improve video reception quality. Result show that this tuning of parameters is not enough to compensate the drop probability increase and thus it is better to aggregate video and general data traffic.
  2nd Workshop on Multilayer Networks; 06/2010
• Conference Proceeding: ETOMIC Advanced Network Monitoring System for Future Internet Experimentation

  I. Csabai, A. Fekete, P. Hága, B. Hullár, G. Kurucz, S. Laki, P. Mátray, J. Stéger, G. Vattay, F. Espina, S. G. Jimenez, M. Izal, E. Magana, D. Morato, J. Aracil, F. Gomez, I. Gonzalez, S. Lopez-Buedo, V. Moreno, J. Ramos
  TRIDENTCOM, Berlin, Germany; 01/2010
• Source

  Available from: Santiago Garcia-Jimenez

  Conference Proceeding: IP addresses distribution in Internet and its application on reduction methods for IP alias resolution

  S. Garcia-Jimenez, E. Magana, M. Izal, D. Morato
  [show abstract] [hide abstract]
  ABSTRACT: Discovery of Internet topology is an important and open task. It is difficulted by the high number of networks and internetworking equipments, and even by the dynamic of those interconnections. Mapping Internet at router-level needs to identify IP addresses that belong to the same router. This is called IP address alias resolution and classical methods in the state of the art like Ally need to test IP addresses in pairs. This means a very high cost in traffic generated and time consumption, specially with an increasing topology size. Some methods have been proposed to reduce the number of pairs of IP addresses to compare based on the TTL or IP identifier fields from the IP header. However both need extra traffic and they have problems with the probing distribution between several probing nodes. This paper proposes to use the peculiar distribution of IP addresses in Internet autonomous systems in order to reduce the number of IP addresses to compare. The difference between pairs of IP addresses is used to know a priori if they are candidates to be alias with certain probability. Performance evaluation has been made using Planetlab and Etomic measurement platforms. The paper justifies the reduction method, obtaining high reduction ratios without injecting extra traffic in the network and with the possibility to distribute the process for alias resolution.
  Local Computer Networks, 2009. LCN 2009. IEEE 34th Conference on; 11/2009
• Source

  Available from: Santiago Garcia-Jimenez

  Conference Proceeding: Improving efficiency of IP alias resolution based on offsets between IP addresses

  S. Garcia-Jimenez, E. Magana, D. Morato, M. Izal
  [show abstract] [hide abstract]
  ABSTRACT: In order to get a router-level topology in Internet, IP address alias resolution techniques allow to identify IP addresses that belong to the same router. There are several proposals to make this identification, some based on active measurements and others based on inference studies. The former provides more accuracy and completeness, however efficiency is very low because of the high number of probes needed. These methods probe IP addresses in pairs. With thousands or even more IP addresses to check for aliases, the number of tests gets too high. In order to reduce the number of probes, we propose to select the pairs of IP addresses to test for aliasing using information available a priori. This selection will be based on the offset (numerical distance) between the IP addresses to test. We will show that we can improve efficiency of active alias identification with almost no loss on completeness and without generating probing traffic. The technique is also adaptable to a distributed measurement scenario.
  Teletraffic Congress, 2009. ITC 21 2009. 21st International; 10/2009
• Conference Proceeding: Performance Analysis of OBS Edge Nodes for Video Streaming

  F. Espina, M. Izal, D. Morato, E. Magana
  [show abstract] [hide abstract]
  ABSTRACT: OBS networks offer a highly efficient transport infrastructure for bursty data traffic. Video streaming content distribution networks are a clear candidate to use this promising technology. Traffic injected into an OBS network is a burst arrival process whose characteristics depend not only on input traffic parameters but also on design parameters of the OBS network. The properties of this traffic will dictate how it is affected by transmision over the OBS core and thus the user-perceived quality of the video stream that is delivered at the edge of the network. This paper evaluates different parameters in the ingress node that affect the losses suffered by the input traffic. Rules for the optimum selection of these parameters are presented: number of wavelengths, buffer size, timer value. The results show the strong dependence of losses on the timer value selected at the burst creation node.
  Computer Communications and Networks, 2009. ICCCN 2009. Proceedings of 18th Internatonal Conference on; 09/2009