It required the use of ephemeral IP address, which can be a waste of IP space
It only worked if there was one destination network, as Next-Hop Tunnel Bindings (NHTBs) did not address which source network traffic came from
Traffic selectors were introduced as feature starting in Junos 12.1X46-D10 (SRX200, SRX1400, and SRX3k series) and Junos 17.3R1 (SRX300, SRX1500, SRX4k, and SRX5k series) for IKEv1. IKEv2 support was added in Junos 15.1X49-D100, meaning this is only available for the SRX300, SRX1500, SRX4k, and SRX5k series.
I was hoping that title would catch your attention.
First and foremost this is a technical blog to discuss neat tricks and tips that I use daily, but sometime it’s a good idea to jump off the path and take a look at what is going on in the tech world. It is high time we start looking past traditional security firewalls or Next-Generation Firewalls and see where the path takes us.
For starters, I was recently at the Juniper Ambassador’s Conference and got to speak with the brilliant minds at Juniper Networks. I am quite sure everyone has heard about the significant changes that has been occurring at Juniper, and like many of you I had my concerns/reservations. While it is important to note is that there are still plenty of opportunities to improve the realm of Junos security in the short term I am excited for what is to come.
I feel that there is always going to be a need for traditional hardware firewalls in the network. Certain features make it extremely tough to remove hardware appliances completely; in particular I am talking about the edge firewalls that handle massive amounts of IPSEC tunnels or NATing public/private IP’s. In the future it would not be a long shot to put security functions in other parts of the network. As an example by moving firewall functions to the hypervisor then we can reduce the need of massive firewalls at the head end.
Let’s look at this idea for a moment. Consider the following traditional network:
Typically you would have your network segments trunked to an interface on a firewall, or a unique interface per vlan directly connected to the firewall. This works great until you run out of interfaces, bandwidth, or processing power of the firewall – especially for that pesky intra-zone traffic!
Now consider adding security features to the hypervisor, such as a virtual firewall that connects its external interface to a flat vlan, and its internal interface to a specific vlan on the virtual switch. A diagram of such an idea is shown below:
By offloading basic firewall or even IPS features to the hypervisor (which has far more compute power than that of a single hardware firewall) we can now free up the firewall to do more important tasks, and increase our scalability significantly! Combining this solution with some of the cool tools like Firefly Packer to help with automating these deployments you can have a significantly faster turnaround time for the needs of your network. This type of design also helps with reducing the failure domain of the network – if an issue crops up one of the hypervisor firewalls it only affects one group of devices, instead of causing an entire network outage. Smaller failure domains = higher overall stability.
Now certainly there are still a bunch of unanswered questions about designs like these, but this is the start of a significant change in how we all can view security and its application to the network. Sometimes it helps to take a step back from what features are missing in a device, and instead look at the opportunities that exist today and in the future.
I have seen this question several times on the Juniper Forums, so I decided to post a quick write up on how to build a route-based VPN to a 3rd party device, such as a Cisco ASA, with multiple subnets on each side. The answer is more straightforward than you think.