The paper "On the Performance Benefits of Multihoming Route Control" written by A Akella et al. in IEEE/ACM Transactions on Networking February 2008 estimates the possible gain of performances while correctly route traffic in multihomed enterprise environments.

The paper focus on two metrics: the RTT (called turnaround time) and the throughput of http-based downloads.

Intelligent Route Control systems are tools that give the oportunity for multihomed ASes to modify the routes according to some performance criteria.

The paper "Avoiding Oscillations due to Intelligent Route Control Systems" written by Gao et al. at INFOCOM'06 shows, like the paper "Can Coexisting Overlays Inadvertenly Step on Each Other" (Keralapura et al., ICNP'05), that IRCs can lead to traffic oscilliations causing performances degradation.

The paper pin-points that the problem comes from two pitfalls:

The paper "ISP and Egress Path Selection for Multihomed Networks" written by Dhamdhere and Dovrolis and presented at IEEE INFOCOM'06 discusses a solution to select the best ISPs for multihommed stub depending on traffic patterns of the stub.

The idea is simple, first, determine the traffic top X prefixes of the stub. Determine the possible ISPs for the stub and use stochastic techniques to detemine the subset of ISP to subscribe to and how to perform the best egress path selection.

The paper titeled "Bandwidth estimation: metrics, measurement techniques, and tools" (R Prasad, C Dovrolis, M Murray, K Claffy - Network, IEEE, 2003) is divided in three main chapters. First, it defines the three following metrics:
- Capacity: the maximum possible IP layer transfer rate.
- Available bandwidth: the unused, or spare, capacity of a link during a certain time period.
- Bulk Transfer Capacity (BTC): the maximum throuhput obtainable by a single TCP connection (depends on many factor like rtt, window size, TCP implementation).

Introduction

In this small tutorial, we present how to setup CentOS guests with the standard tools proposed by CentOS.

By default, CentOS gives good tools to rapidly create networked guests, see by yourself:

Host preparation

• Configure Xen for private networking:
  1. Virtual networks can be configured in /etc/libvirt/qemu/networks/autostart/default.xml. The default configuration is good enough for us but feel free to modify it:
     

     <network>
       <name>default</name>