3710 S McClintock Ave RTH 418
University of Southern California
Los Angeles, CA 90089


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I am a Computer Engineering PhD student in USC under supervision of Ramesh Govindan and Minlan Yu in NSL. I have B.Sc. and M.Sc. degree in Information Technology Engineering from Sharif University of Technology (Tehran, Iran).

This is my new website and is still under construction. If you want something from my old website check this link.

Recent projects

Datacenter measurement

The high level goal of the project is to develop a monitoring module in the network hypervisor based on software defined networking paradigm that help the cloud datacenter operators monitor the network just as a single switch. One important usecase for this module is detecting the heavy hitters and hierarchical heavy hitters. Now imagine that every tenant wants this service. How can we allocate networking resources to keep all measurement tasks accurate using allocation and admission control schemes. Challenges include estimating accuracy of tasks without a ground-truth, admission control without knowing the size of a task beforehand, and per-switch resource allocation in a scalable way.

vCRIB: A virtualized Rule Information Base

Consider many management policies each creating lots of OpenFlow rules such as Accept/Deny rules for access control. How can we pack them all in the switches on/off the shortest path with limited resources? There are three challenges: 1) rules can overlap and separating them may change their semantics, so we partition overlapping rules to decouple them. 2) In packing partitions on switches, we must put partitions with similar rules on the same switch to save resources. We solved this as a special version of bin-packing problem by an approximation algorithm with provable bound. Then we extend it to the case that partition similarities depend on the switch resource model (hardware vs. software switch) and 3) Forwarding flows imposes traffic overhead. For example, dropping a flow on ToR has one hop overhead comparing to drop it at server. We minimize traffic overhead using an online greedy algorithm. We evaluated the system using large scale simulation and a prototype using OVS and showed that vCRIB could find many non-trivial placements with less than 10% traffic overhead.

MRM: A service market for Map-Reduce

Data centers are a bunch of computers which are connected through an interconnection network usually offering computing, storage, and … services. On the other hand, the cloud computing model defines a novel role for mobile, social, and health related computing using the reliability and efficiency of these data centers. As a result of vast application of cloud computing, jobs on these datacenters can have various types with different desired requirements. For example some jobs are deadline driven while others just only need some computation resources. Duration and the amount of computation needed for each job is not available before running the job while they are important factors in defining the service model to guarantee the quality of service. In this project, first we propose a way to predict job duration in map-reduce framework and then use that to define a deadline-driven service market.

More projects


9/1/2013 MRM got into SOCC as a poster
Although it could not get into SOCC as a paper, I will participate in SOCC to get more feedback in the poster session.

7/14/2013 MobiSim v3 is out
I implemented many changes in MobiSim in 2010 but never have published them with the hope that I can create a complete network simulator someday. Now, I tried to commit whatever I have done as I think my field of research will not meet mobility in near future. See the project page here.

4/27/2013 SDM paper got into HotSDN
My Software Defined Measurement paper got in HotSDN'13. I cannot participate but hope everyone like it.

3/1/2013 See my data center measurement poster in NSDI
In NSDI'13 poster session, I will present the preliminary work for the data center measurement system. I hope the short paper get into HotSDN'13, too.

12/4/2012 vCRIB got into NSDI
Yay! vCRIB paper got into NSDI. It seems that our lab did a great job this year in NSDI, we have 3 papers.

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