5 page fit

Jinghao Shi
1 parent 25aeff1f
Showing 5 changed files with 29 additions and 29 deletions
conclusion.tex
design.tex
introduction.tex
investigation.tex
related.tex
 \section{Conclusions}
 \label{sec:conclusion}
  
-In this paper, we show that reciprocal \wifi{} sharing opportunities do exist in real
-life scenarios through extensive analysis of the \PhoneLab{} \wifi{} dataset. We
-propose and present the design of \wisefi{}, a system that detects reciprocal
-sharing opportunities, enable \wifi{} sharing and monitor the \wifi{} usage and
-performance to ensure the sharing remains reciprocal.
+In this paper, we show that reciprocal \wifi{} sharing opportunities do exist in
+real life scenarios through extensive analysis of the \PhoneLab{} \wifi{}
+dataset. We present the design of \wisefi{}, a system that detects
+reciprocal sharing opportunities, enable \wifi{} sharing and monitor the \wifi{}
+usage and performance to ensure the sharing remains reciprocal.
  
 We are currently implementing a \wisefi{} system prototype, which includes a
 \wisefi{} Android application, dynamic AP configuration API support on OpenWRT
@@ -38,14 +38,14 @@ described in Section~\ref{subsec:reciprocal}.
 \label{subsec:sharing}
  
 Once the reciprocal sharing opportunities are discovered, the \wisefi{} server
-can distribute such information to the \wisefi{} application on smartphone,
-which will prompt users to establish \wifi{} sharing. The sharing mechanism must
-meet two goals: control and protection. First, the system should be able to
-control the sharing, including granting the access of home AP to other \wisefi{}
-users, and revoking the access when the reciprocal sharing opportunity no longer
-exists. Second, the system should protect the home network from other \wisefi{}
-users by sharing access only to the Internet, and protecting private resources
-such as home network printers or storage.
+distributes such information to the \wisefi{} application on smartphone, which
+prompts user to establish \wifi{} sharing. The sharing mechanism must meet two
+goals: \textit{control} and \textit{protection}. First, the system should be
+able to control the sharing, including granting the access of home AP to other
+\wisefi{} users, and more importantly, revoking the access when needed. Second,
+the system should protect the home network from other \wisefi{} users by sharing
+access only to the Internet, and protecting private resources such as home
+network printers or storage.
  
 Some mid-to-high end wireless routers support the \textit{virtual network}
 feature, where multiple virtual \wifi{} networks are emulated by a single router
@@ -78,7 +78,7 @@ all devices is still tedious.
  
 To overcome this challenge, we propose a dynamic \wifi{} AP configuration API
 with two simple interfaces: \texttt{getAuthClients} and \texttt{setWhiteList}.
-The semantics of the interfaces are as follows. \texttt{getAuthClients} simply
+The semantics of the interfaces are as follows. \texttt{getAuthClients} 
 returns all the MAC addresses of clients that are currently associated with the
 AP through normal authentication. In home \wifi{} network scenario, this
 interface shall return only the MAC addresses of user's own \wifi{} devices. On
@@ -133,7 +133,7 @@ sharing remains reciprocal. There are two reasons why this is necessary: one is
 obvious and another is obscure.
  
 First, it is obviously important to ensure that the sharing remains reciprocal
-in long term to provide incentives for both parties to participate the sharing.
+to provide incentives for both parties to participate the sharing.
 For instance, suppose after the system has established reciprocal \wifi{} sharing
 between Alice and Bob, and Bob decides to deploy an extra AP at his home which
 makes him no longer benefit from sharing Alice's home AP. The system should
@@ -64,7 +64,7 @@ But how often is reciprocal \wifi{} sharing beneficial and possible in
 practice? To explore these questions, we begin in
 Section~\ref{sec:investigation} by analyzing a dataset collected on the
 \PhoneLab{}~smartphone testbed containing \num{21192417} \wifi{} scan results
-from 254~smartphones over 5~months (\S~\ref{sec:investigation}). Despite the
+from 254~smartphones over 5~months. Despite the
 fact that the geographic extent of the dataset is suburban Buffalo, which as
 a city has a population density an order of magnitude lower than
 densely-populated areas like Manhattan, we still find that many users would
@@ -79,12 +79,12 @@ that provide better signal most of the time?
 \sloppy{%
 To answer the first question, we inspect scan results that are reported during
 \wifi{} sessions with home APs. For each such scan result, we identify the
- currently associated home AP, $AP_{home}$, and the AP with best RSSI among all
- reported APs, denoted as $AP_{best}$. We are particularly interested in
- \textit{sub-optimal} cases, where: (1) $AP_{home} \neq AP_{best}$ and (2) the
- device never connects to $AP_{best}$ in the dataset. Such cases indicate that the device
- could potentially improve its \wifi{} performance by connecting to a neighbor
- AP which has a strong signal yet it does not have access to that AP. Note that
+ currently associated home AP, $AP_{home}$, and the AP with best RSSI, denoted
+ as $AP_{best}$. We are particularly interested in \textit{sub-optimal} cases,
+ where: (1) $AP_{home} \neq AP_{best}$ and (2) the device never connects to
+ $AP_{best}$ in the dataset. Such cases indicate that the device could
+ potentially improve its \wifi{} performance by connecting to a neighbor AP
+ which has a strong signal yet it does not have access to that AP. Note that
 here we consider RSSI as a hint in determining the \textit{optimal} AP and it
 is well understood that RSSI does not directly translate to \wifi{}
 performance, which we will discuss in Section~\ref{sec:challenges}. Also note
@@ -100,7 +100,7 @@ that provide better signal most of the time?
 \label{fig:suboptimal}
 \end{figure}
  
-We classify all scan results reported during \wifi{} sessions with home APs into
+We classify all scan results reported during home \wifi{} sessions into
 two categories: sub-optimal and the rest. For each device, we calculate the
 percentage of time when the scan results indicate sub-optimal association.
 Figure~\ref{fig:suboptimal} shows the CDF of this percentage for 
@@ -110,7 +110,7 @@ their home APs usually provides best signal (sub-optimal percentage less than
 usually carefully positioned to provide good coverage. Second, we notice
 that for certain number (15\%) of devices, their home APs failed to provide best
 signal for more than 50\% of the time, suggesting that these users may benefit
-from sharing the \wifi{} access of their neighbor APs.
+from sharing the \wifi{} access of neighbor APs.
  
 Next, we want to answer the question when the device is in a sub-optimal association
 with its home AP, are there \textit{dominant} neighbor APs that
-\section{Related Work}
+\section{Related Works}
 \label{sec:related}
  
 OpenWireless movement~\cite{openwireless} is a community effort for ubiquitous
-Internet access. Volunteers participate the community by configuring their
+Internet access. Volunteers configure their
 \wifi{} network with open access and a special SSID, \texttt{openwireless.org},
 to advertise free access. Another goal of OpenWireless is arguably preserving
 user's privacy by blending the user's network activity among all other users who
@@ -22,11 +22,11 @@ neighbor relationship).
  
 There are also rich literature on cooperative \wifi{} sharing. Dimopoulos
 \textit{et al.}~\cite{efstathiou2010controlled} propose a reciprocal Wifi
-sharing mechanism and later on extend it to a large scale peer-to-peer Wifi
+sharing mechanism and later extend it to a large scale peer-to-peer Wifi
 roaming framework~\cite{dimopoulos2010exploiting}. They mostly focus on the
 reciprocal manner of sharing: each user who share his/her WLAN will obtain
 digital proof service (\textit{receipts}), which represent a ``I-owe-you''
 relationship. These receipts can later on be consumed to get reciprocal Wifi
 access from other users. Such reputation mechanisms can also be applied to
-\wisefi{}, although they can be simplified since \wisefi{} focus on sharing
-between two immediate peers with physical colocation relationship.
+\wisefi{}, although they can be simplified since the sharing is between two
+immediate peers with physical colocation relationship.