Network security consists of the provisions made in an underlying computer network infrastructure, policies adopted by the network administrator to protect the network and the network-accessible resources from unauthorized access, and consistent and continuous monitoring and measurement of its effectiveness (or lack) combined together.

Overview of Network Security Technologies

• Firewall
• Virtual Private Network (VPN)
• Intrusion Detection System (IDS) and Intrusion Prevention Systems (IPS)
• Anomaly Detection System
• Authentication, Authorization, and Accounting (AAA) and Identity ManagementNetwork Admission Control

Network security technologies protect your network against the theft and misuse of confidential business information and guards against malicious attacks from Internet-borne viruses and worms. Without network security in place your company risks unauthorized intrusions, network downtime, service disruption, regulatory noncompliance and even legal action. Network security does not rely on one method, but uses a set of barriers that defend your business in different ways. Even if one solution fails, others still stand, guarding your company and its data from a wide variety of network attacks.

TTIV Solution about Security Products Overview

BlueCoat

Cisco

IronPort

Fortinet

F5

Check Point

Juniper

McAfee

Diagram 1.1 TTIV Solutions about Security Products Overview 

FIREWALL
A firewall is an integrated collection of security measures designed to prevent unauthorized electronic access to a networked computer system. It is also a device or set of devices configured to permit, deny, encrypt, decrypt, or proxy all computer traffic between different security domains based upon a set of rules and other criteria.A system designed to prevent unauthorized access to or from a private network. Firewalls can be implemented in both hardware and software, or a combination of both. Firewalls are frequently used to prevent unauthorized Internet users from accessing private networks connected to the Internet, especially intranets. All messages entering or leaving the intranet pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria.

There are several types of firewall techniques:

• Packet filter: Looks at each packet entering or leaving the network and accepts or rejects it based on user-defined rules. Packet filtering is fairly effective and transparent to users, but it is difficult to configure. In addition, it is susceptible to IP spoofing.
• Application gateway: Applies security mechanisms to specific applications, such as FTP and Telnet servers. This is very effective, but can impose a performance degradation.
• Circuit-level gateway: Applies security mechanisms when a TCP or UDP connection is established. Once the connection has been made, packets can flow between the hosts without further checking.
• Proxy server: Intercepts all messages entering and leaving the network. The proxy server effectively hides the true network addresses.

 Diagram 1.2 Firewall Technique Overview