IDS mailing list archives
RE: Cisco IDS 4250 vs Sourcefire IS3000 + RNA Sensor
From: "Gary Halleen (ghalleen)" <ghalleen () cisco com>
Date: Wed, 19 Oct 2005 22:00:03 -0700
Tom, Cisco IPS is not simply an inline IDS. Yes, it utilizes signatures to identify attacks. In addition, though, it performs these actions, all of which are features of an IPS: 1. Traffic Normalization 2. Anomaly Detection 3. Stateful Inspection 4. Protocol Compliance 5. Denial-of-Service (DoS) Protection Our IPS was tested by NSS in their most recent testing, and the results, which were quite good, are publicly available. You can access the report at http://www.nss.co.uk/ips/edition3/index.htm I don't believe a network-based IPS exists yet that can truly provide zero-day, or zero-hour, worm protection all by itself. Utilizing capabilities like netflow, perhaps a product can identify when a worm may have infected, or is trying to infect, your network, but stop it? We have a long-term agreement with Trend Micro, and provide very fast protection against worms. Our IPS products (appliances, blades, and IOS routing software) are now able to have anti-worm and anti-virus signatures applied automatically within minutes of a new worm or virus being discovered in the wild. Many people call this fast response to a worm or virus "zero-day", but in my opinion this is simply fast response to threats. True zero-day protection implies that no updates are needed at all to provide the protection, because protection occurs immediately. Our true, zero-day protection is host-based with Cisco Security Agent (CSA). CSA is behavior-based, and does not utilize signatures at all. It is able to protect hosts from all types of attacks by defining what is considered good and bad. The base protections are predefined in the product, but can obviously be modified all you like. No single network device can ever provide 100% protection, regardless of what a vendor may have told you. They can strive to provide near-100%, but real protection must be applied in layers, with each successive layer enhancing the protection provided by the other layers. This is what our SAFE blueprint discusses. You mention stateful firewalling as a feature of an IPS, but I disagree with this assumption. Stateful inspection of traffic is certainly a feature, but not stateful firewalling, which implies all other features of a firewall product, like network address translation and VPN. Additionally, there is a big difference in the default policies deployed on an IPS versus a firewall. The default policy on an IPS is "Permit all traffic except that which is malicious or explicitly defined." The default policy on a firewall is "Permit only traffic which is defined, and deny all other traffic." Proof of this difference in default policies can be seen by simply looking at the perceived need for software/hardware failure protection on IPS products. Have you ever heard a customer say "Hey Mr. Vendor, I want to make sure that if my firewall fails, all traffic will pass unfiltered to the servers sitting behind it." However, this type of statement is common when they deploy IPS. For customers who desire IPS combined with stateful firewalling, we've introduced our ASA-5500-series appliances. With these products, you combine best-of-breed firewall and IPS products in an easy to use chassis. You have very granular control over which traffic is firewalled, and which traffic is also sent to the IPS. You are also able to choose whether the specified traffic is inspected inline or passively, and you can combine both methods for different types of traffic. Gary ________________________________ From: Tom Hamlin [mailto:finacksyn () yahoo co uk] Sent: Wednesday, October 19, 2005 4:45 AM To: Gary Halleen (ghalleen); Tim Holman; Jonathan Gauntt; focus-ids () securityfocus com Subject: RE: Cisco IDS 4250 vs Sourcefire IS3000 + RNA Sensor Since when has an inline IDS become an IPS, or am I missing something? IDS vendors are really confusing the market by using IPS terminology. An inline IDS does partially fulfil the definition of an IPS, by using signatures to protect against known exploits, but what about all the other stuff an IPS does, like: 1. Anomaly detection / protocol validation 2. DOS protection 3. Stateful firewall An IPS is a xth generation firewall, and not a 2nd generation IDS. An IDS only solves part of the problem that a network IPS is trying to address. I know this is all marketing speak, but it's confusing the technical community here, and decent IPS products are being thrown into the same bin as inline-IDS 'IPSes' and being discarded as stillborn technology, when they're clearly not. My company suffered severe downtime having deployed an inline-IDS, that was touted to provide zero-day protection against the worm that got straight through it. The Security Manager lost his job for putting his complete faith in a market-leading IDS vendor who told him that their latest and greatest solution would defend against such things. We have since re-evaluated our security infrastructure, and put things in their correct places. The IDS is on the inside, in passive mode, whereas the IPS is outside the firewall, ensuring the entire network is protected. Although it's OK to put an IDS inline, don't expect it to offer 100% protection, and at least compliment the IDS with dedicated upstream IPS technology. Matthew "Gary Halleen (ghalleen)" <ghalleen () cisco com> wrote: The IDS-4250, with 5.0 or later code on it, will function as either an IDS, or an IPS, or both. Multiple Cisco 4200-series sensors can be clustered through etherchannel load-balancing to scale throughput, as well as provide failure protection, if your needs change. This is available both in passive mode (IDS) and inline modes (IPS). Gary -----Original Message----- From: Tim Holman [mailto:tim_holman () hotmail com] Sent: Thursday, October 13, 2005 4:32 AM To: Jonathan Gauntt; focus-ids () securityfocus com Subject: Re: Cisco IDS 4250 vs Sourcefire IS3000 + RNA Sensor Hi Jonathan, Wouldn't you rather block bad traffic, rather than detect it? Most companies are moving away from IDS as a protection mechanism, because: 1) It only detects, and doesn't effectively block intrusions 2) Problems with false positives, as by using pattern matching signatures, there is always a chance that these patterns also appear in valid traffic 3) Management overheads. An IDS can only be a reasonably effective prevention method if there is someone on hand 24/7 to monitor logs and take immediate action on intrusions. Even then , the intrusion has got in, as admins very rarely use the active blocking features of an IDS (namely sending RST packets to kill connections, or modifying upstream ACLs), as these are too likely to have an effect on valid traffic 4) There is absolutely no protection for rate-based attacks (SYN, TCP, UDP floods) 5) Without maintaining a L3/4 connection/state table, there is no way an IDS can be truly stateful. 100% statefulness means that everything from the initial SYN to the final RST/FIN packet of a connection is stored in a connection table. This requires the device to be INLINE, and operating at L3. This is the only way a protection device can provide effective defence against L3 attacks. An offline IDS cannot do this. I would recommend looking at IPS products instead, so something that you can postion inline and get immediate value from. If you feel the Cisco IDS is getting a little tired, then an IPS will also help take the load off it, by getting rid of Internet white noise, providing additional firewall filtering, and also defence against rate-based attacks. A true IPS will focus on defining what is GOOD traffic, and assuming all else is BAD (and dropping it). By doing this, zero-day attacks can be virtually be eliminated, as they all ultimately rely on abuse of a valid protocol in the hope of slipping past your protection mechanisms and onto your network. This works quite well in conjucntion with an IDS, that focuses on searching traffic for badness. Replacing like for like (IDS for IDS) is not going to give you much value, and even the market analysts are recommending against it. IDS isn't dead. Far off it, but use it for what it's good for - DETECTION and FORENSICS, and not as a device that can insure your network against rate-based and zero-day attacks. Regards, Tim ----- Original Message ----- From: "Jonathan Gauntt" To: Sent: Wednesday, October 12, 2005 5:57 PM Subject: Cisco IDS 4250 vs Sourcefire IS3000 + RNA Sensor > Hi, > > We are currently running a Cisco IDS 4250 that monitors our internal > traffic. We essentially use this device for historical reporting because > we > are a medical oriented facility with at least 100 3rd party connections to > us besides the 8000 employees. > > I am considering upgrading the Cisco IDS 4250 to the XL to handle higher > throughput but have been evaluating the Sourcefire IS300 and their RNA > sensor. > > I have the ability to purchase the Sourcefire unit or upgrade the 4250. > > Sourcefire claims that they are superior with state full IDS inspection > and > an overall better product. > > Does anyone have any thoughts on these two products? I have about $100k > in > my budget to spend. > > Thanks, > > > Jonathan > > > > ------------------------------------------------------------------------ > Test Your IDS > > Is your IDS deployed correctly? > Find out quickly and easily by testing it > with real-world attacks from CORE IMPACT. > Go to http://www.securityfocus.com/sponsor/CoreSecurity_focus-ids_040708 > to learn more. > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------ Test Your IDS Is your IDS deployed correctly? Find out quickly and easily by testing it with real-world attacks from CORE IMPACT. Go to http://www.securityfocus.com/sponsor/CoreSecurity_focus-ids_040708 to learn more. ------------------------------------------------------------------------ ------------------------------------------------------------------------ Test Your IDS Is your IDS deployed correctly? Find out quickly and easily by testing it with real-world attacks from CORE IMPACT. Go to http://www.securityfocus.com/sponsor/CoreSecurity_focus-ids_040708 to learn more. ------------------------------------------------------------------------ ________________________________ How much mail storage do you get for free? Yahoo! Mail gives you 1GB! Get Yahoo! Mail <http://us.rd.yahoo.com/mail/uk/taglines/hotmail_com/storage/*http://uk. mail.yahoo.com> ------------------------------------------------------------------------ Test Your IDS Is your IDS deployed correctly? Find out quickly and easily by testing it with real-world attacks from CORE IMPACT. Go to http://www.securityfocus.com/sponsor/CoreSecurity_focus-ids_040708 to learn more. ------------------------------------------------------------------------
Current thread:
- RE: Cisco IDS 4250 vs Sourcefire IS3000 + RNA Sensor Gary Halleen (ghalleen) (Oct 18)
- RE: Cisco IDS 4250 vs Sourcefire IS3000 + RNA Sensor FinAckSyn (Oct 20)
- <Possible follow-ups>
- RE: Cisco IDS 4250 vs Sourcefire IS3000 + RNA Sensor Gary Halleen (ghalleen) (Oct 20)