Junos OS

Working on a site to site VPN between an ASA and a SRX100. I am assuming the SRX100 is using IKEv2, by default. Is the SRX100 using IKEV2 or IKEV1 by default?

Aaron

SRX uses IKEv1 by default. To set it to v2:

root# set security ike gateway test version ?
Possible completions:
v1-only The connection must be initiated using IKE version 1
v2-only The connection must be initiated using IKE version 2

Here's a config example: 

http://www.juniper.net/documentation/en_US/junos12.1/topics/example/ipsec-route-based-vpn-configuring-ikev2.html

Juniper has a nice tool to help you build a vpn on srx

https://www.juniper.net/customers/support/configtools/vpnconfig.html

hope this helps you a bit

Thank you for your help everyone!