Are Tomorrow’s Firewalls Finally Here Today?
by George Lawton
In an effort to efficiently meet the challenge of the new cyberthreats that arise almost daily, network administrators are beginning to adopt next-generation firewalls in significant numbers.
NGFWs represent an evolution of traditional firewalls to incorporate a variety of security functionalities into a single box or integrated platform.
John Grady, senior research analyst at market-analysis firm IDC, said NGFWs typically include firewall, intrusion-prevention, and identity-based access-control capabilities, as well as the ability to manage the execution of Web-based applications through the firewall.
Consolidating such functions in one device reduces the cost of installing and maintaining security functionality.
NGFWs also offer easier management of, as well as more granular inspection of, control of, and visibility into network traffic than traditional firewalls, explained Patrick Bedwell, security vendor Fortinet’s vice president of product marketing.
Despite such promise, the technology faces performance and implementation challenges that could hinder its adoption.
In 1988, AT&T developed the first firewalls, which offered the basic recognition and filtering of packets that represented potential network threats.
More advanced capabilities for closely monitoring connections going through the firewall—for information such as IP addresses, packet sequences, and ports that transmissions try to access—were introduced in the early 1990s.
Shortly thereafter, vendors began adding the ability to monitor traffic from some Web applications and protocols, and to deduce behaviors that could be associated with malware attacks.
Meanwhile, in 1984, researchers began working on intrusion-detection systems (IDSs), which evolved into intrusion-prevention systems.
In 2008, firewall vendors began incorporating IPS technology into their products. The approach monitors networks and other systems for malicious activity, logs relevant information, reports events, and tries to block problems before they can occur.
This led to the creation of NGFWs, which are beginning to become popular.
Leading NGFW products include Barracuda Networks’ NG Firewall, Check Point Software Technologies’ R75, Cisco Systems’ ASA 5500, Fortinet’s FortiGate 5001B, McAfee’s Enterprise Firewall v8, Palo Alto Networks’ PA 500, and SonicWALL’s Next Generation Firewall.
Traditional firewalls block some traffic from applications based primarily on the port or protocol used.
Most application traffic now enters corporate networks via HTTP, whereas in the past it might have entered via, for example, native TCP, native User Datagram Protocol, or Real Time Messaging Protocol.
Legacy firewalls can neither differentiate between wanted and unwanted traffic nor detect malicious applications tunneling within legitimate communications. To receive any HTTP traffic, users thus must let all HTTP traffic pass through their firewalls.
This renders such firewalls less than adequate for many organizations.
Like similar security approaches, NGFWs rely on template-based pattern matching, in which they compare traffic against a database of known threats.
This complex evaluation requires NGFWs to analyze more packets than traditional firewalls handle and to use larger threat databases.
Rather than just monitor the ports or protocols that arriving packets use, NGFWs attempt to reassemble the packets in a way that reveals complex behavior patterns in packet activity; malware being transferred via e-mail, messaging, or Web applications; or unauthorized behavior during user visits to sites such as Facebook.
By looking for a wider array of security issues, NGFWs offer greater visibility than traditional firewalls into network traffic.
The new firewalls can also perform fine-grained analysis of application-traffic patterns. For example, these capabilities could let a firewall allow connections to Facebook but block communications from a problematic application running on the social-networking site.
New interfaces between unified NGFW management consoles and multiple types of security scanners traditionally managed separately let administrators better set fine-grained security policies and analyze suspicious traffic patterns more quickly and easily.
NGFWs offer intrusion-prevention capabilities, addressing a major problem that many organizations face.
Security experts developed IDS and IPS to conduct deep inspection into packets entering a network, said Greg Young, research vice president at market research firm Gartner Inc.
When an NGFW’s IPS component identifies a possible intrusion, it blocks the connection within the router from which the suspicious traffic is coming.
Some vendors have added reputation-management capabilities to NGFWs.
This enables the new firewalls to run extra security measures, such as blocking traffic associated with IP addresses known to have been sources of malware or intrusion attempts.
These NGFWs work with either their own or other organizations’ threat-intelligence databases of problematic IP addresses.
Another set of NGFW features identifies abnormal activities by using information from administrators about network users’ identities and expected behaviors.
For example, a Sales Department computer shouldn’t be adjusting router settings, explained Gartner’s Young.
If such activities occur, the NGFW blocks the suspicious internal traffic from the network.
NGFWs and Unified Threat Management
There is some question among experts and in the marketplace as to how NGFWs differ from unified-threat-management products.
IDC’s Grady said UTM devices generally include firewall, IPS, and gateway antivirus features, whereas NGFWs incorporate firewalls, IPS, and application-control and reputation-management features. NGFWs are also typically engineered to handle larger traffic loads.
Vendors generally sell UTMs to small and medium-sized businesses or smaller divisions of large organizations, according to Andrew Hoerner, McAfee’s director of marketing for network security.
They generally market NGFWs to larger organizations with higher performance and scalability requirements, he explained.
According to Grady, NGFW devices frequently use powerful processors, specialized chips for various purposes, faster buses, and improved parallel-processing techniques to provide their functionality.
Despite their promise, NGFWs pose potential problems in terms of performance, necessary upgrades to existing security infrastructures, and changes to organizations’ operations.
According to Hoerner, many NGFW vendors have yet to create the tools and services necessary to smoothly migrate existing firewalls and rule sets.
Host systems require substantially more computing horsepower to provide each new level of security that NGFWs offer. Using multiple capabilities can reduce system throughput to as low as 1 percent of previous levels, noted Gartner’s Young.
In addition, Hoerner said, many NGFW vendors have not invested enough in developing their own security intelligence for their products and instead have relied on third parties for such information.
In some cases, he explained, this reduces overall effectiveness and makes firewall management more difficult.
Grady said organizations often must get used to the way NGFWs operate in areas such as security-policy creation.
And, Young added, including too many functions in NGFWs can create complexity and reduce performance. Organizations thus might opt to maintain separate applications to provide security for their critical networks.
Technological improvements and economies of scale appear likely to drive down costs and improve NGFW performance.
Grady said the market for advanced security applications such as NGFWs will continue to grow as the potential cost savings increase and new threats emerge.