if you've enabled 'set security log cache <value>' then you'll see that you can view traffic logs with the command 'show security log' with the number of total security event equal to or less than the cache value. You'll also notice there are some great filtering options for this command.
admin@srx100h> show security log ? Possible completions: <[Enter]> Execute this command ascending Sort in ascending order descending Sort in descending order destination-address Destination address and optional prefix length destination-port Destination port detail Show detail alarm information event-id Event ID filter failure Event was a failure interface-name Name of interface newer-than Events newer than filter (YYYY-MM-DD.HH:MM:SS) older-than Events older than filter (YYYY-MM-DD.HH:MM:SS) process Process that generated the event protocol Protocol filter severity Severity of the event sort-by Sort by selected field source-address Source address and optional prefix length source-port Source port success Event was successful username Username filter | Pipe through a command
but notice the difference in data for IPv4 vs IPv6 traffic below (yes, I have a functional dual-stack network with he.net as my tunnel broker service).
admin@srx100h> show security log | match 2001:470:e0bb | count Count: 35 lines
admin@srx100h> show security log source-address 2001:470:e0bb::/48 No security events were logged matching this filter
admin@srx100h> show security log | match 192.168.13. | count Count: 338 lines