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INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 5, ISSUE 04, APRIL 2016

ISSN 2277-8616

Access Agent: Improving The Performance Of
Access Control Lists
Thelis R. S., Lakshani H. G. S., Samarawickrama S. S., KavinMukesh A., Wickramasinghe W. A. S. M., Dhammearatchi D.
Abstract: The main focus of the proposed research is maintaining the security of a network. Extranet is a popular network among most of the
organizations, where network access is provided to a selected group of outliers. Limiting access to an extranet can be carried out using Access Control
Lists (ACLs) method. However handling the workload of ACLs is an onerous task for the router. The purpose of the proposed research is to improve the
performance and to solidify the security of the ACLs used in a small organization. Using a high performance computer as a dedicated device to share
and handle the router workload is suggested in order to increase the performance of the router when handling ACLs. Methods of detecting and directing
sensitive data is also discussed in this paper. A framework is provided to help increase the efficiency of the ACLs in an organization network using the
above mentioned procedures thus helping the organization’s ACLs performance to be improved, to be more secure and the system to perform faster.
Inbuilt methods of Windows platform or Software for open source platforms can be used to make a computer function as a router. Extended ACL
features allow the determining of the type of packets flowing through the router. Combining these mechanisms allows the ACLs to be improved and
perform in a more efficient manner.
Index terms: Access Control Lists, Extranet, Sensitive data, dedicated device, router workload, Meta-ACL profile, extended ACL
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1

INTRODUCTION

MAINTAINING a secured and faster network is quite a
challenge for a large organization with confidential data
nowadays. Since the rapid growth of networked computers,
security has been a concern. Before the 90s, networks
were rarely used by the general public of heavy internet
users. During these times, security was not considered
critical, however with the addition of more sensitive
information being placed on networks, it would grow in
importance. In the 21st Century accomplishing specific tasks
in every day needs with technology, one need to have a
thorough knowledge of what needs to be performed. The
proposed system try out to reduce the work-load of the
router via allocating the access level to a computer. The
proposed research is directed to computer networks, and
more specifically, to a system and method for security
access to network elements. Network resources and
information are a principle asset of modern companies and
must be protected against unauthorized access for usage,
external threats, updates and violations, since these
resources are being used in various elements such as
switches, routers, signaling transfer points (STPs),
mainframe computers, database servers, etc., Background
of the research and the related researches conducted in
this field are reviewed in chapter II. The approach taken to
provide the solution is briefly described in chapter III. Finally
the conclusion of the research and the future works that can
be done regarding this research are also stated at the end
of the research paper.

2

BACKGROUND AND RELATED RESEARCHES

Various researches have been carried out to discover new
ways to stabilizing or to improve security of a computer
network. The system follows the procedure of Firewalls that
are developed to protect networks from unauthorized
accesses. Various third parties may attempt to penetrate a
network to obtain sensitive information or disrupt the
functioning of the network. Firewalls guard against these
threats and also inspect packets and sessions to determine
if they should be transmitted or dropped. The firewalls have
become a single point of network access which causes the
traffic to be analyzed and controlled. The system implement
a dedicated network device. The device which receive and

transmits network traffic for limit the access to the local
network. The system failed to access the degree of
sensitiveness of their contents. The mechanism
automatically detects privacy requirements of the publisher
of data by the information that is sensitive. The reader with
required qualification only can access such data [6].
Implementing redundancy in a business organization
network is a necessity, thus the use of multiple firewalls is
considered for this research. Policy mining approach is
used to achieve the objectives of the research. An
additional process for network access control policy mining
is used. A method is shown on how to verify security
properties of consistency when firewalls are being
deployed. However this research does not focus on
reducing the workload of the router when handling access
lists, nor does it detect the sensitive data sent by a
particular node. The proposed system will be built with the
capability of tracking and detecting sensitive data and
controlling network traffic. By using a dedicated computer to
perform the tasks of the router, the router workload will be
shared and reduced allowing the router to process faster.
[8] In this research it discusses about how to control access
to data entities in a computer network. It defines a method
that uses a relational database to store the details about
access rights of the users accessing a computer network.
When the user tries to access the network, the application
server will retrieve the access rights of that user with the
use of a query. Then privilege levels for each user will be
defined depending on the data entities the user is allowed
to access. However this research does not facilitate
controlling the packet flow or load balancing of the devices
handling the Access Control. Proposed system discusses
the lacking features of this research including router load
balancing when handling Access Lists and the detecting
and controlling of data packet flow .[4] The system follow
the security mechanism called security policy to guard
against external attacks and to control internal user access
to the network elements. The network security mechanisms
include an authentication server, a credential server, and a
network element access server. System follow security
mechanisms that can effectively control access to network
elements and protect network resources. The system uses
the
concept
of
network-wide
centralized
user
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administration. The concept controls the access to
individual network elements and access to network
resources. System controls the user access by
authentication method. Credential server manage the user
privileges in the network associated with the authentication
server. The network elements includes a separate local
access control means operating with security mechanisms
to facilitate secure communication of data over the network.
The system does not consider about the dedicated devices
used for access controlling. The proposed system follow
this method to increase the secure level of the network to
better levels by implement a dedicated network device such
as a router positioned between a local network and an
external network, most of the time the Internet, or between
local networks. The system selectively examine packet
payloads to figure out when new channels are to be
opened. This mechanism help the system to be well
maintained [5]. In this research it mainly focuses on
dynamic access control for enterprise networks. Enterprise
network security involves set of real time, defensive
methods that are being used in an enterprise to protect its
business network from external threats to their IT system.
The research argues that the network layer with
mechanisms for dynamic access control can remedy these
ills. The research propose a system for securing enterprise
networks, where the network elements themselves enforce
dynamic access control policies based on both flow-level
information and real-time alerts. This research does not
involve about router load balancing, data tracking or
detecting sensitive data. In the proposed system the
research group will discuss about router load balancing,
data tracking and detect sensitive data. [7] The research
focuses on user privacy in Online Social Networks (OSN).
Users tend to expose their sensitive information
accidentally in online textual messages because of the lack
of technical knowledge of the user or the inflexibility of the
access control mechanisms used in OSNs. The system
detects such sensitive data depending on the publisher of
the message with the use of an automatic semantic
annotation mechanism. Then the system automatically
generates a cleansed version of the publication according
to the targeted audience of the data to control the access.
Although this system keeps track of sensitive data and
secure user access privacy, it does not provide a solution to
prevent unauthorized users from accessing any of the
sensitive data. The proposed system will track the sensitive
data and prevent them from being accessed by third parties
in order to secure the network access and sensitive data
privacy [10]. Requirements for specification and
implementation of access control policies have become
more important in industrial networked systems. A twofold
model for analysis of ACL policies includes three main
components. They are; security policy document, control
user access, high level network policy. Security policy
document in the proposed system covers some important
parts. For controlling user access, it needs a Meta ACL is
generated. In the proposed system, the main purpose is to
find a method to automate ACL system and also lessen the
workload of a router. High level network policy should
provide facilities to have a simpler, faster and more secured
network. In order to do load balancing and good
performance, and also to do access control, with the use of
a dedicated device, our group intends to test whether a

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router and computer or a computer itself can handle ACL
processing because computer is a more intelligent device
compared to a router. The concept of style sheets
transformation driven firewall access list generation will be
used to secure network access. Controlling data traffic can
be done in a few ways. Use two gateway routers in a larger
LAN. Using ACL permitted actions, the traffic can be
divided among two routers [9]. The research discusses
about global server load balancing (GSLB). GSLB is
popular for its disaster recovery functionality as well as for
more intelligent direction of traffic of optimal site selection.
In this research it is focused on identifying of the selected
best IP addresses from GSLB algorithm and the selection
metric used to decide on an IP address as the best one and
the data includes a count of the selected best IP addresses
selected via the GSLB algorithm. This research does not
involve any type of controlling of data traffic, controlling user
access or securing network access. Therefore in the
proposed system we would facilitate traffic controlling, user
access controlling, securing network access and detection
of sensitive data. [2] This research is a concept, and also
can be recognized as a method to make a secured network
system which contains a few important components. They
are; Meta ACL profile, data registry, security policy
document, securing network policy, usage of firewalls.
When there is a large network with multiple users, routers
and switches with a lot of user access controls, it is difficult
to create user access lists to every router and switch
manually. It will increase the workload of a gateway device
of a network. A router doing traffic filtering can deploy ACLs
with thousands of rules. Due to the complications regarding
ACL configuration language, large ACLs can easily become
redundant, inconsistent, and difficult to optimize or even
understand. There will be considerable amount of routers in
the network topology of the proposed system. If it is done
manually, all of the ACLs need to be configured in a
consistent manner to enforce the corporate security policy.
Although it takes a lot of time and it may not be accurate at
all. There will be redundant ACLs, which is inconsistent. In
order to overcome this problem, we need a novel
framework to automate ACL analysis and make the network
simpler. A set of algorithms is introduced to detect and
remove redundant rules, discover and repair inconsistent
rules, merge overlapping or adjacent rules, mapping an
ACL with complex interleaving permit/deny rules to a more
readable state containing all permits or denies, and finally
generate a meta-ACL profile based on all ACLs along a
network path. Traffic filtering is also needed. Data registry
will keep the useful information about the network such as
information related to the topology of the network.
Documents that contain network security policies are linked
to the registry data structure. When automating, and
working with different devices, data registry is very
important. Network security policy, is an outline for the
network access with some defined rules. It determines how
policies are enforced and lays out some of the basic
architecture of the organization’s security or network
environment. It will cover the use of passwords and
encryption, email attachments and more. For the proposed
system we need a good network security policy which will
balance the security and the network traffic both. Firewall
devices block certain kinds of network traffic, forming a
barrier between a trusted and non-trusted network. But,
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ISSN 2277-8616

when there is a larger network with many divisions,
requirements may differ making it more complex. [3] It is the
task of the network administrator to correctly implement
ACL in a large network environments of enterprise security
policy which is a difficult task. With the topology of a
plurality of routers, all ACL needs in a consistent manner
the implementation of enterprise security policy
configuration. In such a situation, manual analyzation of
ACLs to ensure security policy is installed correctly is nearly
an impossible task. In this research paper, an algorithm is
introduced to detect and remove redundant rules, find and
fix inconsistent provisions, merge overlapping or adjacent
rules map complex cross license ACL in a more readable
form containing all licenses or to reject the final calculation
based on a blend of all ACL files and to generate a metaACL profile following the processes. This meta-ACL profile
will help the Administrator understand the flow of traffic of
the network once it is applied to the traffic filtering ACLs. A
library named ACL Analysis (ACLA) is created based on the
information provided on the research paper. A new
framework for automated ACL analysis is provided in this
research paper, greatly simplifying implementation and
verification of corporate security policies at the network
level security policy implementation, including configuration
using ACL packet classification policy. [1]

instead of a router. It can be divided in to two main parts.
They are Windows based and Linux based. The main
requirement is that the computer has to have at least two
fast network interfaces installed in the system. Computer
can either have two network cards or one network card and
a wireless card. On Windows computers, the process of
setting up this router functionality is called Internet
Connection Sharing. A mechanism known as IP forwarding
can also be used to make a computer function as a router
connecting 2 to 3 separate networks. Linux based methods;
there are four networking software. They are DD-WRT X86,
ZeroShell, RouterOS, Untangle. These software are made
for small networks using few computers without the need of
a router. Computer is an intelligent machine that will help to
identify sensitive data. The mechanism automatically
detects the information that is sensitive depending on the
privacy requirements of the publisher of data, with regard to
the type of reader that may access such data. Finally,
access control mechanism automatically creates sanitized
versions of the user’s publications according to the type of
reader that accesses them. In order to reduce the workload
of the router user can implement ACLs in the computers. It
will be more helpful to prevent threats including hackers,
data theft etc. The components of this research are
discussed in sub sections below.

3

3.1

OUR APPROACH

Router Load Balancing

Currently, if there is a network with bigger LANs connected
with different departments, the organization needs different
access controls for different departments. That means
routers in the network need to be programmed with different
access control lists (ACLs). ACL is a helpful feature for
controlling the filtering process of network traffic as well as
providing an added feature of security. Using Network ACLs
can be done the following; Permit or deny incoming traffic
depending on remote subnet IPv4 address range to a
virtual machine input endpoint.
 Use of blacklist IP addresses.
 Creating multiple rules per Virtual Machine (VM)
endpoint.
 Specify up to 50 ACL rules per VM endpoint.
 Use rule ordering to ensure the correct series of rules
are applied to a given VM endpoint (from lowest to the
highest).
 Specify an ACL for a specific remote subnet IPv4
address.
There are two types of ACLs defined by the Cisco.
Standard ACLs: This type of ACL is the simplest one since
it only considers IP addresses when filtering. In other
words, this ACL can be used only when there’s a need to
permit or deny traffic from a certain host IP address or a
certain source network. Extended ACLs: This type of ACL
is the most preferred one and the most advanced as well.
Using this type of ACL it allows to filter traffic based on:
Source IP address, Destination IP address, Protocol (TCP
or UDP), Port Numbers (Ftp 21 etc.). In the proposed
research, to enhance the security and control IP traffic,
Extended ACLs are suggested. If ACL is programmed
manually, it is a very time consuming task. There will be a
number of redundant ACLs which will make the network
slower. In the proposed research the main purpose is to
use a computer which is faster and can do more work load

Fig. 1. IP forwarding using Windows XP platform (Source:
http://www.home-network-help.comhttps://www.scribd.com/images/xxp-routernetwork.jpg.pagespeed.ic.BjDSsKeQZx.jpg)

The proposed research suggests a method that turning a
computer into a gateway and router for network to balance
the router workload. In Windows platform this can be
performed using either IP forwarding method or Internet
Connection Sharing. The software DD-WRT X86,
ZeroShell, RouterOS and Untangle can be used to make a
computer perform as a router in a small network. It is an
ideal way to get advanced features over what is already
provided in consumer-level routers. By converting computer
into a router to share the workload, the intention is to free
some of the work of the router to make it perform faster and
to prevent the router from overloading/ overheating. The
targeted network is a small sized business organization
network which allows access for a selected group of outliers
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(Extranet). Adding some features such as virtual LANs,
multiple SSIDs, hotspot and captive portal, and VPN server
and client capabilities are possible in a computer that acts
as a router. Some machines provide network-wide antivirus,
spam, and Web filtering. The proposed research includes a
method that can receive the ordered list based on a set of
performance metrics related to access conditions to host
servers to arrange network addresses corresponding to the
domain name. The order of IP addresses, and typically
selects the first IP address on the list, when accessing the
corresponding host server. The ordered list of network
address is sent as a response to the query. The data
related to the query is tracked. This tracking feature allows
better understanding of Global Server Load Balancing
policy decisions such as those related to performance,
maintenance, troubleshooting and intelligent installation of
large-scale flexible Global Server Load Balancing networks
[2].

3.2

Controlling User Access

Fig. 2. Fortinet ACL whitelist and blacklist [Source:
http://help.fortinet.com/coyotepoint/10-32f/Content/Protection/AcessContList_Summary.gif)

Various techniques are associated with controlling user
accesses to objects and other data entities .There are
 Access Control Lists (ACLs)
 Storage of a capabilities list
 Firewalls
Among these techniques, the proposed research will be
using ACLs: This technique which is commonly used in file
systems, involves the storage of an ACL for each data
entity to which the access is to be controlled. The ACL for a
given data entity will usually be in a list of the users that
have access to the data entity, together with the access
rights of each such user regarding the data entity. Each
time a request is sent to the entity, the data entity's ACL is
searched to determine whether the requested access is
authorized. ACLs possesses two types of lists to control
the user access to a network depending on the user’s IP
address, namely Whitelist and Blacklist. The whitelist allows
access for a specific IP address or an address range. If the

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address or the range is included in the blacklist that packet
will be dropped. If the address or range is a sub part of a
larger range defined in the blacklist, the whitelist will take
precedence for the specified addresses. If the blacklist is
free of addresses and there are only addresses listed in the
whitelist, then only the addresses listed in the whitelist are
allowed and connections from all other addresses are
blocked.

3.3
Controlling Data Traffic
ACLs support data traffic controlling. The process is done in
the router by controlling whether the packets received are
forwarded or dropped based on criteria specified within the
ACL. These criteria may include source IP address,
destination IP address or any other relevant information of
the packets received. ACL can be implemented in firewall
routers between an external network and the LAN network
or it can be implemented between separate parts of the
same network. The focus of this research is to
implementation of the router between the LAN and the
external network to secure the data that is flowing out of the
network or to prevent irrelevant traffic generated from
unauthorized third party outliers. Use of Extended ACLs
(figure 5 in Appendix) are suggested for this research
implying that the ACLs must be implemented for each
protocol of the network. The criteria statements have to be
clearly defined as every ACL contains “deny all traffic”
criteria statement at the end of the statements list, which
will drop whatever the packet that does not match any other
criteria defined. The order in which the criteria statements
are listed deemed important as the list will be checked in a
sequential order once a packet is received, until a match is
found. The statements listed below the matching statement
will not be checked, hence an ordered ACL will help the
router to perform faster and more efficiently.
3.4
Detecting Data Types and Data tracking
The type of packets forwarded or blocked can also be
determined using ACLs. As stated above in section C,
implementing Extended ACLs require implementation of
ACLs for each protocol on a network interface, which allows
the tracking of the type of data flowing through the network,
for example: sharing of emails can be allowed in the
network while preventing the TELNET communications [11].
Tracking of the source and destination of a packet can be
determined using the IP addresses. Using the statements
listed in ACLs, it is suggested to generate a meta-ACL
profile [1] [3] to provide a better understanding of the
network including the destination and the source of the
packet sent to the outside of the network. Analyzation of the
meta-ACL profile will allow the network administrator to
identify any sort of unauthorized access to the network as
well as leakage of sensitive information of the organization
to a third party through an employee.

4

CONCLUSION

Maintaining a well performing ACL is very important in a
network. This research paper discusses about a method to
share the workload of the router that is handling the ACL,
with a computer that is solely dedicated for the stated
purpose to prevent the router from overloading. This paper
also focuses on the technology of tracking the data flowing
outside of an extranet with the use of ACLs to detect
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sensitive data and prevent it from reaching unauthorized
third parties. Internet Connection Sharing and IP forwarding
methods are used for Windows platforms and Software:
DD-WRT X86, ZeroShell, RouterOS and Untangle are used
for Open source platforms to convert a computer into a
router to share the workload of a router. Extended ACLs
and IP addresses are used to detect the type, source and
destination of the packets sent from the network and a
packet will be dropped if it is directed to an unauthorized
destination. A meta-ACL profile will be generated based on
the criteria of the ACL to allow a better understanding of the
network.
A combination of these technologies are
suggested by the research group to improve the
performance of a router inside a small organization
network.

5

FUTURE WORK

The major drawback of the proposed research is that it is
only limited to a small organization extranet where only a
few network interfaces or sub interfaces are implemented.
With the use of a higher performance computer it might be
possible to apply this system to a larger network. Analyzing
of the machine generated meta-ACL profile may take less
effort if an algorithm is introduced to perform the said task
using the router itself or the computer sharing the router
workload.

ACKNOWLEDGEMENT
We thank Mr. Dhishan Dhammearatchi for providing the
assistance and feedbacks/ comments to carry out this
research and steering us in the right direction. We would
also like to thank the SLIIT Computing (PVT) LTD and other
individuals/groups that helped us achieve this target.

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197-211, 2001.

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[Online].
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APPENDIX

Meta-ACL profile

Global server/router load balancing

Sorted IP list

Selecting best IP address

Data tracking

Data registry

Security policy document

Controls user access

Securing network access

Registration database

Dedicated device(s) for access
control

High level network policy

Use firewalls

Detect sensitive data

Control data traffic

Features
Simplified access list

TABLE 1
RELATED RESEARCHES AND COMPONENTS

Researches
ACLA:
A
framework
for
Access Control
List
analysis
and optimization
[1]
Statistical
tracking
of
global
server
load balancing
for selecting the
best
network
address
from
ordered list of
network
addresses
based on a set
of performance
metrics [2]
Style
sheets
transformation
driven
firewall
access
list
generation [3]
System
and
method
for
controlling
access to data
entries
in
a
computer
network [4]
Security system
and method for
network element
access [5]
Access control
for networks[6]
Resonance:
dynamic access
control
for
enterprise
networks. [7]
Mining a high
level
access
control policy in
a network with
multiple firewalls
[8]

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A twofold model
for the analysis
of
access
control policies
in
industrial
networked
systems [9]
Privacy driven
access control
in
social
networks
by
means
of
automatic
semantic
annotations [10]
Proposed
system

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Fig. 3. Outbound ACL
(Source: http://www.cisco.com/c/en/us/td/docs/security/asa/asa70/configuration/guide/config/nwaccess.html)

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Fig. 5. Extended IP ACL (Source: http://www.technology-training.co.uk/ciscoipaccesslists_49.php)

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