Routing Policy and Firewall Filters

Enhanced firewall filter processing on MPC10E and MPC11E line cards (MX Series)—Starting in Junos OS Release 21.2R1, MX Series routers evaluate the terms attached to a firewall filter in an optimized fashion, and the maximum number of terms per filter increases to 8000.
[See Understanding Firewall Filter Match Conditions.]
TCP SYN cookie (MX480 and MX960 with SPC3 card)—Starting in Junos OS Release 21.2R1, we support the TCP SYN cookie. You can configure syn-cookie for the TCP protocol for source and destination.

[See Configuring Network Attack Protection With IDS Screens for Next Gen Services.]