Network Security Implemenation Flashcards
What is AAA
Authentication
Authorization
Accounting
Framework for controlling remote access to system resources
Give all the remote networking protocols that implement AAA
RADIUS
TACACS
TACACS+
Diameter
Definition of Authentication
The method of uniquely validating a particular entity or individual’s credentials.
Give all Authentication factors
Something you know, such as a password
Something you have, such as a token or access card
Something you are, including physical characteristics such as fingerprints or a retina pattern
Somewhere you are or are not
Something you do; for example, a keystroke logger that measures how hard you press the keys while typing, or how long the keys remain pressed
Definition of MFA
MFA: Multifactor authentication is an authentication scheme that requires the validation of at least two of the possible authentication factors.
Definition of Two Factor Aunthentication
Two-factor authentication: An authentication scheme that requires validation of two authentication factors.
What is Local Authentication and give examples
When users are off the network, rather than authenticating to a network server database, they authenticate to a local system account
Windows: SAM registry hive
Linux: /etc/passwd or /etc/shadow file
What do users need for Local Authentication
Biometric authentication
Passphrase
Token device
Definition of SSO
Single sign-on is a mechanism where a single user authentication provides access to all the devices or applications where the user has permission.
Definition of LDAP
Lightweight Directory Access Protocol (LDAP) is a directory service protocol that defines how a client can access information, perform operations, and share directory data on a directory server.
What is a digital certificate
Digital certificate: An electronic document that associates credentials with a public key.
What is a CA
Digital certificate: An electronic document that associates credentials with a public key.
What is the purpose of a certificate
Users, devices, services, and applications can all hold certificates.
Certificates validate the certificate holder’s identity.
Certificates are a way to distribute the holder’s public key.
A root CA is typically the first or only CA installed.
A root certificate is typically a self-signed certificate that identifies the root CA.
Defintion of Kerberos
Kerberos: A popular open-source authentication protocol that is based on a time-sensitive ticket-granting system.
Definition of TGT
TGT: (Ticket-Granting Ticket) Used in Kerberos. It is an encrypted file requested from a Ticket-Granting Server that is only valid for a short time to access network services.
Definition of TGS
TGS: (Ticket-Granting Server) Used by Kerberos. It is the logical key distribution center and functions as a trusted third party to issue Ticket-Granting Tickets.
Give the process of Kerberos
1 A user logs on to the domain.
2 The user requests a Ticket Granting Ticket (TGT) from the authenticating server.
3 The authenticating server responds with a time-stamped TGT.
4 The user presents the TGT back to the authenticating server and requests a service ticket to access a specific resource.
5 The authenticating server responds with a service ticket.
6 The user presents the service ticket to the resource.
7 The resource authenticates the user and allows access.
Give a full description of RADIUS
Enables a server to provide standardized, centralized authentication for remote users.
Configure one RADIUS server; configure the other remote access servers as RADIUS clients.
RADIUS clients will pass all authentication requests to the RADIUS server for verification.
Can centralize user configuration, remote access policies, and usage logging on a RADIUS server.
Supported by VPN servers, Ethernet switches requiring authentication, wireless access points (WAPs), as well as other types of network devices.
Give a full description of TACAS+
Authentication protocols that provide centralized authentication and authorization services for remote users.
TACACS includes process-wide encryption for authentication; RADIUS encrypts only passwords.
TACACS uses TCP instead of UDP and supports multiple protocols. Extensions to the TACACS protocols exist, such as Cisco’s TACACS+ and XTACACS.
TACACS uses TCP port 49 and also supports multifactor authentication.
TACACS+ is considered more secure and more scalable than RADIUS because it accepts login requests and authenticates the access credentials of the user.
TACACS+ is not compatible with TACACS because it uses an advanced version of the TACACS algorithm.
Give a full description of RDP
The backbone of Microsoft’s Remote Desktop system.
Its capabilities include data encryption, remote audio and printing, access to local files, and redirection of the host’s disk drives and peripheral ports.
In client versions, 6.1 and later, any application that can be accessed via the normal remote desktop can serve as a standalone remote application.
The server listens on port 3389.
The server component, the terminal server, is available on most Windows operating systems, except for Windows Vista® Home Edition.
A desktop client is available for most operating systems.
Give a full description of VNC
A platform-independent desktop sharing system.
VNC client and server software is available for almost any operating system (and for Java®), so a VNC viewer on a Linux system can connect to a VNC server on a
Microsoft system and vice versa.
VNC uses the Remote Frame Buffer (RFB) protocol, which allows the client and server to determine the best version of RFB they can support during a session.
VNC is not an inherently secure system but does offer varying levels of password and content encryption, depending on the implementation.
Definition of NAC
Network access control (NAC) is a general term for the collected protocols, policies, and hardware that govern access on network interconnections.
Give a full descrpition of NAC
NAC provides an additional security layer that scans devices for conformance and allows or quarantines updates to meet policy standards.
Security professionals will deploy a NAC policy according to an organization’s needs based on three main elements:
=The authentication method
=Endpoint vulnerability assessment
Network security enforcement
Once the NAC policy is determined, professionals must determine where NAC will be deployed within their network structure.
What is IEEE 802.1x
IEEE 802.1x is a standard for securing networks by implementing Extensible Authentication Protocol (EAP) as the authentication protocol over either a wired or wireless Ethernet LAN, rather than the more traditional implementation of EAP over Point-to-Point Protocol (PPP).
What does IEEE 802.1x employ
Employs an authentication service, such as RADIUS, to secure clients, removing the need to implement security features in APs, which typically do not have the memory or processing resources to support complex authentication functions.
Give a full description of IEEE 802.1x
The switch or wireless access point puts the client session on hold and does not allow it to enter the network until either the device or user is authenticated and authorized by a RADIUS server.
Wireless hotspots that require a user name and password in a browser are using 802.1x.
It is an IEEE standard used to provide a Port-based Network Access Control (PNAC), using the 802.11 protocols.
802.1x uses EAP to provide user authentication against a directory service.
What is an ACL
An Access Control List is a set of data that is used to control access to a resource.
What data is included in an ACL
Data includes items such as: User names Passwords Time and date IP addresses MAC addresses
What resources are included in an ACL
Resources include items such as:
Devices
Files
Networks
Give all the characteristics of an ACL
ACLS can be configured to explicitly allow or deny access to resources.
An implicit deny-all clause placed at the end of an ACL will deny permissions to all traffic that is not explicitly permitted in the list.
Definition of a Firewall
A software program or a hardware device (or a combination of both) that protects a device or network from unauthorized access by blocking unsolicited traffic.
Give a description of a Packet Filter
The simplest firewall implementation. They work at the OSI Network layer (Layer 3). Each network packet is compared either to a set of default criteria or to a set of rules configured by an administrator. Based on the rules, the packet is passed or dropped, or a message is sent back to the originator. Packet filters are usually a part of a router.
Give a description of a Stateful Inspection
Works at the OSI Session layer (Layer 5) by monitoring the condition, or state, of the connection. Monitors the TCP connection establishment to determine if a request is legitimate. Stateful inspection firewalls are also known as circuit-level gateways.
Give a description of a proxy
Works at the OSI Application layer (Layer 7) and requires incoming and outgoing packets to have the proxy to access services. This functionality allows proxy firewalls to filter application-specific commands. Can be used to log user activity and logons, which offers administrators a high level of security but significantly affects network performance. Also known as Application-level gateways.
Give a description of a hybrid
Combines the functionality of all of the above and operates at the OSI Network, Session, and Application layers simultaneously.
Definition of a UTM
Unified Threat Management (UTM) is a network security solution that is used to monitor and manage a wide variety of security-related applications and infrastructure components through a single management console.
True or False
UTMs can be network appliances or cloud services.
True
Give all the security functions that UTMs provide
UTMs provide multiple security functions such as: Network firewalling Network intrusion prevention Anti-malware VPN Spam and content filtering Load balancing Data leak prevention On-appliance reporting
Definition of IANA
IANA: (Internet Assigned Number Authority) An international organization established in 1993 to govern the use of IP addresses. The Internet Corporation for Assigned Names and Numbers (ICANN) is now responsible for leasing IP addresses worldwide.
Definition of a Port
IANA: (Internet Assigned Number Authority) An international organization established in 1993 to govern the use of IP addresses. The Internet Corporation for Assigned Names and Numbers (ICANN) is now responsible for leasing IP addresses worldwide.
What is the purpose of a dynamic port
Dynamic ports: assigned by a client operating system as needed when there is a request for service.
What port is FTP assigned to
20,21
What port is SMTP assigned to
25
What port is DNS assigned to
53
What port is HTTP assigned to
80
What port is POP3 assigned to
110
What port is HTTPS assigned to
443
What port is SMB assigned to
445
What is the purpose of registered ports
Registered ports: available to user processes and listed as a convenience by the IANA.
What do all ports have?
All ports are assigned a number between 0 and 65,535.
Give the concept of Open Ports
A TCP or UDP port number is configured to accept packets, unlike a closed port (which rejects connections or ignores all packets directed at it).
Characteristics of Open Ports
Every open port is a potential security vulnerability.
When ports are open and not needed, consider disabling them.
Give the protocol and service of the port 21
Protocol: TCP and Service: FTP
Give the protocol and service of the port 22
Protocol: TCP and Service: SSH
Give the protocol and service of the port 23
Protocol: TCP and Service: Telnet
Give the protocol and service of the port 25
Protocol: TCP and Service: SMTP
Give the protocol and service of the port 53
Protocol: TCP/UDP and Service: DNS
Give the protocol and service of the port 80
Protocol: TCP and Service: HTTP
Give the protocol and service of the port 110
Protocol: TCP and Service: POP3
Give the protocol and service of port 135
Protocol: TCP/UDP
and Service: Windows RPC
Give the protocol and service of port 137
Protocol: TCP/UDP
and Service: NetBIOS over TCP/IP