Friday, October 28, 2016

Software-Defined Simulations for Continuous Development of Cloud and Data Center Networks

Today I am presenting my full paper at CoopIS. This is one of the core works of my PhD, and something that I have been working for, for the last 2 years. The presentation and the abstract are given below. The full paper can be found here.

Today is also my last day at Rhodes, and back to Portugal tomorrow very early morning! It was an amazing week at this lovely island with full of sessions and networking. I also had another paper in the conference last year as well, which was held in the same location, same days. However, I was unable to physically join the conference due to clash in travel schedules. Luckily, this time I made it!


Abstract: Cloud network systems and applications are tested in simulation and emulation environments prior to physical deployments, at different stages of development. Software-Defined Networking (SDN) enables separating logic and execution from the data plane consisting of switches and hosts, to a logically centralized control plane. The global view and control available to the controller enable incremental updates, management, and allocation of resources to the networks. However, unlike the physical networks or the networks emulated by the emulators, current network simulators still lack integration with the SDN controllers.

Hence, currently it is impossible to efficiently orchestrate a simulated network through a centralized controller, or realistically model the controller algorithms and SDN architectures without having the resources for a one-to-one emulation. To address this, this paper presents SDNSim, an SDN simulation middleware, which leverages the principles of SDN for continuous development of cloud and data center networks. SDNSim is an “SDN-aware” network simulator that integrates with the controller through plugins for southbound protocols such as OpenFlow, to execute the algorithms incrementally thus deployed in the control plane.

Wednesday, October 26, 2016

Selective Redundancy in Network-as-a-Service: Differentiated QoS in Multi-Tenant Clouds

I arrived at the beautiful Greek island of Greece this Sunday to present one of my papers at CoopIS conference and another at EI2N workshop. Today I presented my first paper at EI2N. The presentation and abstract are given below.



Abstract: Data centers consist of various users with multiple roles and differentiated levels of access. Tenant execution flows can be of different priorities based on the role of the tenant and the nature of the process. Traditionally enterprise network optimizations are made at each specific layer, from the physical layer to the application layer. However, a cross-layer optimization of cloud networks would utilize the data available to each of the layers in a more efficient manner.

This paper proposes an approach and architecture for differentiated quality of service (QoS). By employing a selective redundancy in a controlled manner, end-to-end delivery is guaranteed for priority tenant application flows despite congestion. The architecture, in a higher level, focuses on exploiting the global knowledge of the underlying network readily available to the Software-Defined Networking (SDN) controller to cater the requirements of the tenant applications. QoS is guaranteed to the critical tenant flows in multi-tenant clouds by cross-layer enhancements across the network and application layers.

Wednesday, October 12, 2016

Atlanta Finishing Touches and the Return to Portugal

Finally, the day came to return to Portugal. As expected, we were left with a considerable amount of stuff to be thrown away or left behind (?) in Atlanta. We attempted to sell a few. We have two Facebook selling groups in Atlanta - one private to Emory University students and staff. Interestingly many of our stuff created a large interest, and some were even bought by the students promptly.

However, one troll group, belonging to an Emory University fraternity decided to troll on my posts.



It was 4 guys named Max, Alex, Zach, and Kyle trolling together. Apparently I have no time to deal with Facebook trolls. I was in Facebook for very short time to sell the stuff and deactivate the account again. Interestingly, the trolls all share the profile pictures - appearing in each others' profile picture. The group did not have a group administrator, or the administrator is unable to or unwilling to reprimand the trolls. 

The Internet troll and bully culture is very dangerous. I have read in news that similar fraternity groups in the US trolling new students, particularly the female students. In extreme cases, online bullying has lead to suicides. These trolls, invite their victims to "just kill themselves".

Troll towards me is harmless, except the fact that my 'business' failed. :P The trolls belonging to the Emory University's Kappa Sigma #20 fraternity (as retrieved from their Facebook profiles) did not get anything out of this except some childish pleasure.

Luckily, we found a church that accepts the free stuff from neighbourhoods. It was win-win. We did a charity, and felt better. Received the blessings of the church. On the other hand, we indeed wasted a lot of time waiting for those who confirmed to buy the stuff. The students cancelled at the last moment (literally), after confirmed to buy, and we waited for them for the whole day to arrive.

We still had some decent students who indeed came and bought the stuff as discussed. This was my first experience as a seller, and I learned a lot. It was my first time being trolled online too. 

Now I am back to Portugal - my familiar lands with more familiar faces and no trolls around. Summer in Portugal was gone when I am back though. Already cold and rainy. Autumn is here, as I resumed my work at INESC-ID Lisboa.