Wednesday, November 30, 2016

Worst of LinkedIn: Those who warn of scammers in a scamming way!

So we all know that there are so many scammers in LinkedIn by now. Many of them try to get views or attention to their profile by posing as a recruiter in a city like Dubai or Doha, or by posting silly mathematical questions. The worse is those who fall for this scam, and write down their email address to the public display and to be scrawled by the spam bots. Some just "like" the status, or type "interested" or "pls review my profile", as that is the best way to prove their competent in the posted job.
Worst scammers of LinkedIn

Now the worst kind of scammers: see the above screenshot.

The status, by default, shows only the first 5 lines. For the entire message, you need to press "Show more". Hence, the unsuspecting LinkedIn users give their contact details as they would do for a LinkedIn job posting I discussed before. They would not read and realize that this status was posted as a warning.

I will explain why these guys who attempt to give light to the con recruiters in LinkedIn are the worst. First, if he was genuine, he would have started the message with the warning, such as "Pls do not fall for this type of scams in LinkedIn:", instead of making the warning hide deep below the advertisement. If you go through the comments, almost everyone has given their contact details, with only a very few commenting how others have misinterpreted this gentleman's kind gesture. 

Little did they know that this type of statuses are very common and popular. In fact, they serve the same purpose. Getting more views to your profile. These are worse, as they are made to obviously make fool of those who commented. Besides, this trick can be used by anyone, not just recruiters, hence increasing the potential reach of the scam.

Don't be this guy, who ruins LinkedIn for everyone! I have been unsubscribing from everyone who falls for these shit to keep my LinkedIn sane.

Sunday, November 27, 2016

Viseu - a young and thriving Portuguese city

Palacio do gelo
[26th - 27th, Nov] Winter seems to be already here. Viseu is ready for the Christmas.

Tuesday, November 1, 2016

ViTeNA: An SDN-Based Virtual Network Embedding Algorithm for Multi-Tenant Data Centers

We have one more of our papers presented today at NCA. As all the authors are currently busy due to other commitments, we have one of colleagues present the paper for us. The presentation slides and the abstract are given below. 

In the mean time, I resumed my research at INESC-ID. It is almost November, and the sun is still up and shining!



Abstract: Data centers offer computational resources with various levels of guaranteed performance to the tenants, through differentiated Service Level Agreements (SLA). Typically, data center and cloud providers do not extend these guarantees to the networking layer. Since communication is carried over a network shared by all the tenants, the performance that a tenant application can achieve is unpredictable and depends on factors often beyond the tenant’s control.


We propose ViTeNA, a Software-Defined Networking-based virtual network embedding algorithm and approach that aims to solve these problems by using the abstraction of virtual networks. Virtual Tenant Networks (VTN) are isolated from each other, offering virtual networks to each of the tenants, with bandwidth guarantees. Deployed along with a scalable OpenFlow controller, ViTeNA allocates virtual tenant networks in a work-conservative system. Preliminary evaluations on data centers with tree and fat-tree topologies indicate that ViTeNA achieves both high consolidation on the allocation of virtual networks and high data center resource utilization. 

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.


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.