pplication gateways
- Circuit gateways
- MAC layer firewalls
Question 102. What Is The Drawback Of Packet-filtering Router?
The drawback of packet-filtering router includes a lack of auditing and strong authentication.
Question 103. What Are Screened-host Firewall Systems ?
Screened-Host firewall system allows the router to pre-screen packets to minimize the network traffic and load on the internal proxy.
Question 104. What Is The Use Of An Application Proxy?
An Application proxy examines an application layer protocol, such as HTTP, and performs the proxy services.
Question 105. What Are Dual Homed Host Firewalls?
The bastion-host contains two NICs (network interface cards)
One NIC is connected to the external network, and one is connected to the internal network
With two NICs all traffic must physically go through the firewall to move between the internal and external networks.
Question 106. What Is The Use Of Nat?
A technology known as network-address translation (NAT) is commonly implemented to map from real, valid, external IP addresses to ranges of internal IP addresses that are non-routable.
Question 107. What Are Screened-subnet Firewalls?
Consists of two or more internal bastion-hosts, behind a packet-filtering router, with each host protecting the trusted network
The first general model consists of two filtering routers, with one or more dual-homed bastion-host between them
The second general model involves the connection from the outside or untrusted network.
Question 108. What Are Sock Servers?
The SOCKS system is a proprietary circuit-level proxy server that places special SOCKS client-side agents on each workstation.
Question 109. What Are The Recommended Practices In Designing Firewalls?
- All traffic from the trusted network is allowed out
- The firewall device is always inaccessible directly from the public network
- Allow Simple Mail Transport Protocol (SMTP) data to pass through your firewall, but insure it is all routed to a well-configured SMTP gateway to filter and route messaging traffic securel,
- All Internet Control Message Protocol (ICMP) data should be denied
- Block telnet (terminal emulation) access to all internal servers from the public networks
- When Web services are offered outside the firewall, deny HTTP traffic from reaching your internal networks by using some form of proxy access or DMZ architecture.
Question 110. What Are Intrusion Detection Systems(ids)?
IDSs work like burglar alarms
IDSs require complex configurations to provide the level of detection and response desired
An IDS operates as either network-based, when the technology is focused on protecting network information assets, or host-based, when the technology is focused on protecting server or host information assets
IDSs use one of two detection methods, signature-based or statistical anomaly-based.
Question 111. What Are Different Types Of Idss?
- Network-based IDS
- Host-based IDS
- Application-based IDS
- Signature-based IDS
- Statistical Anomaly-Based IDS.
Question 112. Define Nids ?
A network-based IDS(NIDS) resides on a computer or an appliance connected to a segment of an organization’s network and monitors traffic on that network segment,looking for indications of ongoing or successful attacks.
Question 113. What Is Hids?
A Host-based IDS(HIDS) works differently from a network-based version of IDS. A host-based IDS resides on a particular computer or server,known as the host and monitors activity only on that system. HIDs are also known as System Integrity Verifiers as they benchmark and monitorthe status of key system files and detect when an intruder creates ,modifies or deletes monitored files.
Question 114. What Is The Use Of Hids?
A HIDs is also capable of monitoring system configuration databases,such as windows registries,in addition to stored configuration files like .ini,.cfg,and .dat files.
Question 115. What Is Application-based Ids?
A refinement of Host-based IDs is the application-based IDS(AppIDS). The application based IDs examines an application for abnormal incidents. It looks for anomalous occur