Admission Control List

Domain 1

Eric Conrad , ... Joshua Feldman , in CISSP Study Guide (2nd Edition), 2012

Admission control lists

Access control lists (ACLs) are used throughout many Information technology security policies, procedures, and technologies. An access command list is a list of objects; each entry describes the subjects that may access that object. Whatever access attempt by a subject to an object that does not have a matching entry on the ACL volition exist denied. Technologies like firewalls, routers, and any edge technical access device are dependent upon access control lists in order to properly function. One affair to consider when implementing an access control list is to plan for and implement a routine update procedure for those access control lists.

Read total affiliate

URL:

https://world wide web.sciencedirect.com/science/article/pii/B9781597499613000029

Network Security Management

Eric Knipp , ... Edgar Danielyan Technical Editor , in Managing Cisco Network Security (Second Edition), 2002

ACL Manager Overview

ACLM is a component inside the network direction software system known as CiscoWorks2000. CiscoWorks2000 is a highly extensible application suite ideally suited for managing Cisco enterprise networks and devices. For convenience and advisable application, CiscoWorks2000 has numerous sub-components that integrate nether the CiscoWorks2000 software framework. Theses components provide direction solutions for local area networks (LAN) and wide surface area networks (WAN) of the enterprise.

ACLM is included in the CiscoWorks2000 Routed WAN Management Solution set. In addition to ACLM, this set of applications includes the following components:

■

Cisco nGenius Real-Time Monitor

■

CiscoView

■

Resources Managing director Essentials

■

Internetwork Performance Monitor

With these tools, administrators greatly increment configuration, administration, monitoring, and troubleshooting capabilities in large-calibration network deployments. Furthermore, long-term performance insight and network traffic optimization are possible with the CiscoWorks2000 Routed WAN Management Solution. For boosted information regarding the CiscoWorks2000 suite of productions and functionality, refer to the Cisco Web site.

Equally the name implies, ACLM is used to develop and maintain ACLs on Cisco devices. ACLM runs as an integrated component of Resource Manager Essentials and can manage most Cisco IOS routers, access servers, and hubs with an IOS of ten.3 through 12.1. ACLM can likewise manage Catalyst switches running Catalyst IOS version v.3 through five.five.

The Web-based Windows Explorer-like graphical interface provides powerful control of IP and IPX access lists and device access control from nearly whatsoever-where on the network. VLAN and SNMP access control list management is also possible via ACLM. The interface eliminates the complexity and syntactical accuracy required to implement lengthy ACLs via the CLI. Furthermore, ACLM saves fourth dimension and resource through batch configuration of new filters and the consistent and accurate management of existing access lists in a big-calibration network.

ACLM includes several modules used to perform specific actions within the managing director functionality suite. These modules are as follows:

■

Template Manager The Template Manager module is used to construct and maintain ACL templates for the predictable and error-free security management of numerous Cisco devices. Using template manager, administrators tin create appropriate templates for many devices instead of reinventing the wheel for each new network component.

■

Form Manager This module enables the creation of service and network groups or classes. With this module, administrators can save time by designating typical groupings of rules to exist quickly implemented via ACLM.

■

Template Use Magician Administrators use the Template Apply Wizard to apply previously created packet and VLAN filtering ACLs, and line and SNMP ACLs across the network. In conjunction with Template Manager, the wizard module allows administrators to be more efficient when deploying or modifying numerous ACL configurations to devices on the network.

■

Optimizer For additional ACL efficiency of a Cisco device, the Optimizer module tin can be used to audit ACL statement ordering and syntax. Optimizer removes redundant statements and consolidates entries. Moreover, the optimizer module can automatically reorder ACL statements confronting hit rate utilization statistics to provide the utmost in efficiency.

■

DiffViewer DiffViewer assists the administrator in discerning changes to ACLs of unlike versions. Using this module, alteration is hands identifiable making version control and version rollback uncomplicated.

■

ACL Downloader This modules enables the scheduled or manual download of ACLs from Cisco devices in the network.

ACL Manager Device and Software Support

ACLM version one.3 supports most Cisco IOS routers, access servers, and hubs with an IOS of 10.three through 12.1. ACLM can likewise manage Catalyst switches running Catalyst OS version five.3 through 5.five. Using ACLM, administrators can view all ACLs, regardless of type. ACLM includes full support for the following access lists:

■

IP, IP_EXTENDED

■

IPX, IPX_EXTENDED

■

IPX_SAP, IPX_SUMMARY

■

RATE_LIMIT_MAC

■

RATE_LIMIT_PRECEDENCE

■

VACL_Catalyst 6000

Read full affiliate

URL:

https://www.sciencedirect.com/science/commodity/pii/B9781931836562500180

Access Command Lists

Dale Liu , ... Luigi DiGrande , in Cisco CCNA/CCENT Examination 640-802, 640-822, 640-816 Grooming Kit, 2009

Introduction

Access control lists (ACLs) are one of the key building blocks of a network configuration. If y'all fully sympathise how Admission lists are constructed and used, y'all're well on your manner to providing acceptable security to your network. However, if you fail to grasp how wildcard masks are used or how order of operation affects Network Address Translation (NAT), and then yous could very well make your network the next successful target of a hacker. Understanding this topic is important, both for the examination and for your career.

Unlike many technologies you volition learn equally a Cisco Certified Network Acquaintance (CCNA) candidate, ACLs are actually old. Standard ACLs that friction match traffic based on source Internet Protocol (IP) accost were part of IOS viii.three. Since IOS 9 was introduced in 1992, you know ACLs have been office of securing networks for a very long time. For comparison, the first graphical point-and-click Spider web browser Mosaic was introduced in 1993.

In this chapter, we'll cover the virtually important elements of IP ACLs with an accent on the textile required for the CCNA exam. Nosotros'll run into how the most bones ACLs are used and how ACLs have matured over the years. Other topics covered will include how to select which type of ACL to utilise, how to build information technology, how to apply it, and how to troubleshoot it when things go wrong. We'll discover some of the about common ACL errors fabricated by network engineers and how to avert them. Finally, although non required fabric for the exam, we'll learn almost some of the newest ACL technology.

Read full chapter

URL:

https://www.sciencedirect.com/scientific discipline/commodity/pii/B9781597493062000130

Formal Analysis of Policy-Based Security Configurations in Enterprise Networks

Southward.K. Ghosh , ... P. Bera , in Handbook on Securing Cyber-Physical Critical Infrastructure, 2012

Inter-ACL Conflicts

The ACL conflicts may occur between the rules from distributed ACLs, which are treated as Inter-ACL conflicts. The previous department describes the modeling of distributed ACLs every bit access route ACLs betwixt each source and destination pair. Now, under the same access route ACL, say (ARCL (S,D)), the subsuming conflicts may arise from the ACLs forth the aforementioned route from source S to destination D.

For example, consider the the ACL implementation (refer to Table 24-2) for the Test-Net network. The rule3.2 of Access-list 3 and rule4.i of Access-list iv are conflicting forth the access route {R6, R1, and Rii} from ADMIN to ZONE_2. This is considering of the fact that the ssh packets from ADMIN (represented by the IP cake 10.128.*.*) to ZONE_2 (represented by IP block 10.64.*.*) are immune by dominion3.2 (at router Rhalf dozen), which are afterwards blocked by rule4.1 (at router R1). This tin can be revealed every bit connection/routing failure at the end of ZONE_2. This type of conflict betwixt multiple ACLs along an access route is treated equally inter-ACL Inconsistency. This conflict tin can be resolved by replacing dominion4.ane with the following rules:

deny TCP x.128.*.* 10.*.*.* eq ssh;

deny TCP 10.128.*.* 10.129.0.0 0.255.255.

  255 eq ssh;

deny TCP 10.128.*.* 11.0.0.0 0.63.255.

  255 eq ssh

Read full chapter

URL:

https://www.sciencedirect.com/scientific discipline/commodity/pii/B9780124158153000248

Inflow on the Scene

Dale Liu , in Cisco Router and Switch Forensics, 2009

Access Command Lists

Access control lists (ACLs) can give yous pertinent information concerning what/who is allowed to access diverse parts of the network. ACLs can comprise the following data:

▪

What internal Internet Protocol (IP) addresses are allowed or denied to access the Cyberspace

▪

What internal IP addresses are allowed or denied to access certain internal and external IP addresses

▪

What external IP addresses are allowed to enter or pass the router

▪

The subnet masks for the IP addresses listed in the ACL

You may see ACLs like to the post-obit that cake reserved IP addresses from passing through the router. Familiarizing yourself with common ACLs is a skilful idea. This way, you lot can identify which ACLS a router has in place.

▪

ip access-listing extended autosec_iana_reserved_block

▪

deny ip 1.0.0.0 0.255.255.255 any

▪

deny ip ii.0.0.0 0.255.255.255 any

▪

deny ip 5.0.0.0 0.255.255.255 any

or

▪

ip access-list extended autosec_complete_bogon

▪

deny ip 1.0.0.0 0.255.255.255 any

▪

deny ip two.0.0.0 0.255.255.255 whatsoever

▪

deny ip 5.0.0.0 0.255.255.255 any

Tools & Traps…

Access Control Lists

The following are adept sources of information on ACLs:

▪

"Demystifying Cisco Access Control Lists" ( www.networkcomputing.com/907/907ws1.html)

▪

RouterGod, "Don Rex Explains IP Extended Access Lists" (http://routergod.com/donking/)

▪

"Cake Traffic from Prc IP Address Blocks to Protect Your Web Server from Chinese Hackers" (www.parkansky.com/people's republic of china.htm)

Read full chapter

URL:

https://world wide web.sciencedirect.com/science/article/pii/B9781597494182000041

Security Architecture in the Cyberspace of Things

Shancang Li , in Securing the Internet of Things, 2017

2.4.2 Access Control List-Based Systems

The access control list (ACL) is a tabular array that tin tell the IoT arrangement all admission rights each user/application has to particular IoT finish node. Each node or device has a security aspect that identifies its ACL. Fig. 2.3 shows an ACL-based arrangement, in which the almost mutual privileges include the ability to admission or control an IoT device.

Figure 2.iii. ACL-based system.

The ACL-based IoT systems refer to rules that are applied to device or device addresses that are available on an IoT system, each with a permitted list of IoT users/applications.

Read full chapter

URL:

https://world wide web.sciencedirect.com/science/commodity/pii/B9780128044582000020

Logically Segregate Network Traffic

Thomas Porter , Michael Gough , in How to Cheat at VoIP Security, 2007

Access Command Lists

Network access control lists (ACLs) are table-like data structures that usually consist of a single line divided into three parts: a reference number that defines the ACL; a rule (usually permit or deny); and a data design, which may consist of source and/or destination IP addresses, source and/or destination port numbers, masks, and Boolean operators. Other patterns are used, but the ones listed are almost common. ACLs more often than not are practical to the ingress or egress side of an interface.

As a packet traverses the interface, the ACL is scanned from top to bottom—in the verbal order that information technology was entered—for a pattern that matches the incoming packet. Figure 8.14 shows the procedure flow for an access control list. In this case, a packet enters at the top and every bit it negotiates the ACL structure, some portion or portions of the packet are tested for a match at each rule-node. If the lucifer succeeds, then related processing takes place; if at that place is no lucifer, then the parcel information is tested by the adjacent lower node. A default dominion should always be added to process any packets that traverse the entire ACL structure. Note that in this effigy, an ACL dominion has called an additional ACL. This blazon of ACL organization leads to uncommonly fine filtering granularity, but these complex rule sets, unless carefully designed, can be computationally expensive, slowing traffic unacceptably.

Figure viii.14. ACL Flow Diagram—Determination Based upon Lucifer/No Friction match

A general rule-of-thumb is that outbound ACLs are more efficient than inbound ACLs since the inbound logic must be applied to every packet, but the outbound logic is applied only to those packets exiting a particular interface. ACLs usually are applied at layers 3 and four of the OSI model, but some vendors (Cisco and Extreme, for instance) offer layer 2 ACLs, and others (Alteon/Nortel, for example) offering ACLs at layers 5 and to a higher place.

ACLs, in coordination with VLANs, QoS, and firewalls, are powerful tools for segregating VoIP traffic from other traffic. Boosted services may exist permitted or denied based upon the client'due south infrastructure requirements.

Read full chapter

URL:

https://www.sciencedirect.com/science/article/pii/B9781597491693500098

Diagramming the Network Infrastructure

Dale Liu , in Cisco Router and Switch Forensics, 2009

Admission Control Lists

Access control lists (ACLs) are of import in 2 locations inside the network: on network infrastructure components such as routers, and on file servers.

On a router or switch—essentially whatsoever device capable of routing traffic from one segment to some other—y'all tin implement an ACL to help control the menses of traffic. For instance, the headquarters location shown in Figure 5.11 has a DMZ network segment, a main network segment, and an R&D network segment. An ACL, comprising individual access control entries (ACEs) specifying source, destination, and policy, can cause traffic from the R&D network segment to exist allowed to flow to the firewall (green arrow) and out to the Internet, but not to hosts on the main network segment (red arrow). This helps to safeguard services and information on the main network segment from whatsoever the R&D folks are working on today. To document the ACLs, it will be necessary to log in to the device and dump the configuration. Exist sure also to test the configuration past attempting to access resources that the ACLs should deny admission to.

Figure 5.11. ACLs Selectively Permitting or Denying Traffic Based on Source and Destination

On a file server, ACLs are used to let access to shared network resources. About every file server operates on the "night club" basis: "If your name'south not on the list, you lot're not getting in." The implicit permission level is none for all resources. When a user's account (or more specifically, a Security Identifier, or SID) is added to an ACL, information technology is added as an ACE that indicates the SID and the level of admission the SID has been granted. At this point, your name is on the list and yous are permitted access. There are a few twists to the tale, in that not only practise users count nether their own SIDs, just they also inherit and are able to claim the SIDs of groups that their account belongs to, which makes for easier assistants. Additionally, an ACE tin can exist an explicit denial or permission. Deny ACEs override allow ACEs, then although one ACE may explicitly grant you read access, an ACE explicitly denying read/write volition override your read access, leaving y'all with zero access.

Documenting file server ACLs typically involves dumping the ACEs for each shared resource and then resolving group SIDs that are listed down to individual users to determine who actually has what level of access.

Read full chapter

URL:

https://world wide web.sciencedirect.com/scientific discipline/article/pii/B9781597494182000053

Personal Firewalls

In E-mail Virus Protection Handbook, 2000

Admission Command Listing (ACL)

An Admission Command Listing (ACL) is a generic term for any list that is intended to command admission. ACLs are usually used to mean 1 of two things—a list of permissions to a disk or fix of files, and a listing of what sorts of network activity are and are not immune.

An ACL in the file sense is a machinery for enforcing a item set of permissions for a file or directory. This could be either on a per-user or per-procedure basis. For case, if someone is logged into your computers as "guest" you lot might not want them to accept access to your documents. You would have an ACL that said something similar guest:no access. For a process example, consider your Web browser. You lot might desire to have a rule as a backup protection machinery that says your browser can't write to most of your difficult drive. That way, if some attacker takes reward of a hole in your browser software, your fill-in mechanism might relieve you. In that location is an example of this type of ACL in the eSafe section later in this chapter.

A network ACL is used to define which addresses and ports are allowed or blocked. An ACL entry typically includes some portion of the following: an address or range (192.168.0.1, or 192.168.0/24), a list or range of ports (80, 25, >1023), and a protocol blazon (Transmission Control Protocol, or TCP; User Datagram Protocol, or UDP; or Internet Control Message Protocol, or ICMP).

Other things that may be included in an ACL include time data (enforced during sure hours) or temporary entries that may be added in response to other traffic that has gone past.

Since the term ACL is pretty generic, it gets adequately vendor-specific beyond those uncomplicated terms. Some firewall vendors telephone call it a rule set. Some firewalls tin accept much more than complicated things besides just assuasive or not allowing certain ports or files. While discussing specific products in this chapter, there will be a number of examples of ACLs.

Read full chapter

URL:

https://www.sciencedirect.com/science/commodity/pii/B9781928994237500112

MCSE lxx-293: Planning, Implementing, and Maintaining a Security Framework

Martin Grasdal , ... Dr. Thomas W. Shinder Technical Editor , in MCSE (Exam lxx-293) Report Guide, 2003

Securing the Schema

ACLs are used to protect schema objects from unauthorized use in Ad. Members of the Schema Admins group are the only members permitted to have write access to the schema. The but default member of the Schema Admins group is the Administrator account in the root domain of the wood.

You should restrict membership in the Schema Admins group, because extending the schema improperly can take serious consequences to your network. For example, an improper change to the schema tin cause existing objects in the directory to become invalid. If you lot disable a particular aspect in an object class and there are existing objects in that class that comprise that aspect, these objects volition become invalid because they contain an aspect that is not allowed in the class definition.

Read full chapter

URL:

https://www.sciencedirect.com/science/commodity/pii/B9781931836937500154