The day may come when it will be unnecessary to build network perimeter defences with firewalls, but in the meantime corporate network-security experts must find alternatives to address the shortcomings that are pushing firewalls toward extinction.
They must look for equipment that filters at the application layer and supplemental products that proxy encrypted traffic so it can be inspected, experts say.
“A next-generation firewall needs to look within traffic streams and determine whether this is the traffic I expected,” says Rob Whiteley, an analyst with Forrester Research. The key to protection is peering deep into packets to decide what poses a threat and what doesn’t, not merely on what ports it uses, he says.
Firewall vendors already recognize this and have incorporated deep inspection of packets that probe to the application layer to determine the nature of traffic and look for anomalies that can signal malicious behavior, he says.
As businesses consider moving to next-generation firewalls, they should weigh certain key factors, says Greg Young, an analyst with Gartner. These include aligning their replacement schedule with the replacement schedules for other gear that now comes as part of some firewalls in bundles called unified threat management (UTM) devices.
The devices may incorporate antivirus, antispam and content filtering. If they align their firewall, IPS, URL filtering and Web antivirus refresh times they may gain the option of merging them into fewer devices, so customers should check out what their current vendors offer. “You might not have to deploy a new appliance,” he says.
Customers should consider their current firewall vendor for supplemental features, Youg says. Their current vendors will integrate these added protections with the firewall, eliminating the work of making sure the firewall is compatible. “You certainly don’t want to break the firewall when you implement IPS,” Young says. He also recommends weighing the cost of retraining staff to administer a new firewall. It may be worthwhile sticking with the current vendor, he says.