Whilst many IT security professionals regard IPS to be a natural extension of IDS technology, the real answer is that IPS is actually another type of access control mechanism, rather than purely a sister IT security platform to IDS.
It may surprise you to know that the term IPS is actually a lot younger than IDS, and is a colloquial term first used by Andrew Plato, a technical consultant with a major IT security vendor that, way back in the late 1990s, developed the industry’s first IDS platform.
In its purest form, an IPS makes a number of access control decisions based on the content of the application, rather than taking a traditional firewall approach of monitoring IP addresses, ports and other connective links.
Back in 1998, Andrew Plato opined that a good IPS should feature a sophisticated analytical engine, but one that generates as few false positives as possible.
Provided this is the case, he said at the time, then a good IPS has a number of advantages over IDS, since it can sit in line with an IP traffic flow and analyse the data stream in real time.
In addition, most modern IPS solutions also have the ability to analyse Layer 7 protocols such as FTP, HTTP and SMTP, and make decisions on whether to allow – or quarantine – the IP packets as required, even if the data is encrypted.
But are today’s IPS platforms up to the task of scanning IP traffic at the high speeds needed in a modern IT environment?
The problem facing IT professionals is that, with the Internet growing at between 40 and 60 per cent a year (source: Atlas Internet Observatory) – and against the backdrop of a mobile data explosion – it’s important that IPS technology can keep up with this data bandwidth growth and not become the bottleneck in the network.
It’s also becoming clear that, on a typical network of today, users are placing a very load on each port of a multi-10G port system and, whilst there are IPS products available that are capable of supporting a multiple 10 Gbps port topology, providing continuous 10 Gbps throughput on these ports is a something of a challenge.
The most worrying part of this development is how IPS platforms can be scaled to meet the needs of 40G and 100G IPS technologies, which are set be introduced to the IT/networking mix in the next few years.
Until a few years ago, it could be argued that IPS platforms were up to the task, especially since most IPS platforms adopted a core five-stage real-time analysis process that steps through a number of stages as various IT threats are encountered when monitoring an organisation’s data streams that flow both in and out of the IT resource.
The first stage is to bandwidth throttle any suspicious IP traffic to give the organisation’s IT security software a chance to analyse the data stream – let’s take the example of an email message stream – and deal with suspect messages and/or attachments in real time.
If the data is found to be suspect, but does not conform to known infection signatures, then the second stage is for the message’s header to be analysed and, if an infection etc., is found, the data can be quarantined.
The third stage in the analysis process involves performing user management and address validation, typically by applying a number of automated checks to verify whether the message comes from a source previously known to be dangerous.
The fourth stage involves applying an anti-malware and anti-hacking analysis engine for anything suspicious that has passed the first three analysis stages but does not pass muster.
The fifth stage, typically involves using the analysis engine to weed out anything that still looks suspicious for later, manual, analysis by the IT security staff concerned.
However, the increasing sophistication of malware, together with the recursive and obfuscated coding approach taken by an increasingly criminal hacking fraternity – and, of course, the higher network speeds seen on today’s networking systems – means that IPS systems are under pressure to keep up, both in terms of handling the amount of data, but also in having the raw horsepower to run more sophisticated algorithms.
So how serious is the threat of an intrusion?
A recent online poll found that a quarter of respondent firms have suffered a network intrusion. The interactive poll amongst more than 300 attendees found that 25 per cent of respondents had experienced an intrusion incident, with 44 per cent of these incidents occurring within the last 12 months.
The important thing to realise here is that network intrusion events are not just an irritation – as they were back in the early days of IT networking – but they can be commercially damaging.
This is because, unlike the altruistic 1980s – when the `hackers’ of yore tended to be fellow engineers who also had access to the dial-up modems, expertise and other IT resources that were required to gain access to other businesses’ online assets – the majority of attacks today are carried out by highly sophisticated criminal organisations attempting to steal data or hijack computing resources for their own illegal use.
That survey showed that 83 per cent of smaller organisations had experienced a security incident in the last year, compared with 45 per cent two years earlier. The survey also revealed that 90 per cent of all organisations had increased their expenditure on IT security technology, whilst smaller businesses are now spending 10 per cent of their IT budget on security issues, compared to 7 per cent two years ago.
The report attributes the rise partly on the increasing use of cloud computing and social networks within enterprises.
Delving into the study reveals that 15 per cent of large companies noted IPS systems are under pressure to keep up, both in terms of handling the amount of data, but also in having the raw horsepower to run more sophisticated algorithms that their IT resources had been accessed by an unauthorised outsider in the last 12 months, and 25 per cent had suffered a denial-of-service attack – double the number logged in the last survey carried out two years earlier.
The report also found that the rate of adoption of newer technologies has accelerated over the last two years, with most respondents now using wireless networking, remote access and VoIP technologies.
In addition, the number of organisations allowing staff to have remote access to their systems has also increased with around 90 per cent of large companies now offering this facility.
These figures confirm that the online poll is on track and that the number of intrusion incidents is definitely on the rise. This, in turn, is also forcing most organisations to increase the proportion of their IT budget they spend on security technologies.
Raising the security game
Businesses are not just increasing their IT security budgets, however, they are also raising their game when it comes to security strategies. Given this scenario, the key challenge now is scaling these systems to keep up with the increasing bandwidth generated by richer content in emails and on Web sites, more video and teleconferencing and the transition to cloud computing already taking place.
The important thing to realise is that all these innovative services provide a new and high-speed avenue of attack for hackers. And because of this, network security systems need to react in real-time to contain the problem.
To keep up with these high-speed, real-time demands, the traditional approach of network security appliance vendors has been to invest in the development of customized, proprietary hardware. However, a new approach is emerging where off-the-shelf standard PC server hardware is being used negating the need for hardware development.
The poll revealed that the majority of network security appliances being used are still based on proprietary hardware, but for every 3 proprietary systems, there are now 2 systems based on standard PC server hardware.
In the past, PC servers have not been powerful enough to meet the demands of security applications like IPS, but the latest generation of PC servers provide significant processing power and a strong roadmap of increased performance to come.
Researchers have discovered it has now become more economical to build network security appliances based on standard PC server hardware using real-time network analysis adapters to ensure high levels of performance. But, one of the most compelling reasons for considering this approach is the ability to scale performance.
At various key IT events throughout this year, companies have demonstrated a full-throughput 10Gbps IPS system based on 8 instances of a standard SNORT application running in parallel. This technique takes advantage of the multiple CPU cores available in modern PC servers. They can support up to 32 CPU cores, so as the number of cores increases and the power of each core ramps up, the ability to scale performance increases.
Indeed, it’s worth noting that CPU chipmakers such as Intel and AMD are increasing the performance of their chips by as much as 50 per cent on an annualised basis. Can the vendors of proprietary network security appliances keep up with this kind of performance roadmap? Does it even make sense to try?