Max Fragmented Packet Size; Flow Initial Session Timeout (Seconds); Multicast Flow Configuration; Tcp Mss - Juniper NETWORK AND SECURITY MANAGER 2010.4 - CONFIGURING SCREENOS DEVICES GUIDE REV 01 Manual

Max Fragmented Packet Size

Flow Initial Session Timeout (Seconds)

Multicast Flow Configuration

TCP MSS

All TCP MSS

Copyright © 2010, Juniper Networks, Inc.
Use the Max Fragmented Packet Size option to control the maximum size of a packet
fragment generated by the security device. You can set the number value between 1024
and 1500 bytes inclusive. For example, if a received packet is 1500 bytes and this option
is set to 1460 bytes, the device generates two fragment packets: The first is 1460 bytes
and the second is 40 bytes. If you reset this option to 1024, the first fragment packet is
1024 bytes and the second is 476 bytes.
By default, this option is set to none.
Use the Flow Initial Session Timeout to control the number of seconds the security device
keeps an initial TCP session in the session table before dropping it or receiving a FIN or
RST packet. You can set the number of seconds from 20 seconds to 300 seconds.
By default, this option is set to 20 seconds.
In earlier versions, all TCP, UDP, and ICMP traffic was supported by setting policy rules.
Use this option to inspect IDP multicast traffic for devices running ScreenOS 6.3.
Use the TCP MSS option to control how the security device handles the TCP-MSS value
for TCP SYN packets in an IPsec VPN tunnel:
When this option is set to Packet Size, the security device modifies the MSS value in
a TCP packet to avoid fragmentation caused by the IPsec operation. The default MSS
for this option is 1400.
When this option is disabled, the security device does not modify the MSS value in a
TCP packet.
By default, this option is disabled.
NOTE: When you configure a value for the All TCP MSS option, that value
overrides the settings defined for this option.
Use the All TCP-MSS to control how the security device handles the TCP MSS value for
TCP SYN packets in all network traffic:
When this option is set to Packet Size, the security device modifies the MSS value in
a TCP packet to avoid fragmentation by other network components. You can set the
TCP MSS range from 0 to 65,535 bytes; the default MSS for this option is set to none.
Additionally, this option overrides the configuration for TCP MSS (described earlier):
Chapter 4: Advanced Network Settings
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