The Lab

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  • Rejected - packet swallowed
  • Inspected - packet contents passed onto the next stage of inspection
  • Ignored - packet forwarded without any further inspection


OSI LayerRejected Inspected Ignored
DataLink [2]QinQEthernet, VLANeverything else
Network [3]IPv6, IPv4JUMBOIPv4everything else
Transport [4]-TCPeverything else
Application [7]everything elseFIXBGP


Warning
titleMessage Size Restrictions
  • Ethernet
frames are limited to 1540 bytes in size.
  • MTU is set to 1500 bytes.
  • TCP Max Segment Size is enforced to be at or below
1424
  • 1448.


TCP Whitelists & Network Address Translation

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Reflector's parser can return error for a variety of reasons: logon fail, wrong protocol, sanity checks, etc. Some exogenous factors can also call for immediate termination: session timeout, disabled credential, UNPLUG mode, etc. The session store executes this directive by generating a pair of TCP RST frames for each affected session.

Session Drop ReasonSourceExecutorRST GeneratedDescription
TCP_FIN_ACKwireSessionStoreNNormal bilateral TCP termination
TCP_RESETwireSessionStoreNUnilateral (client) TCP reset
LOGIN_FAILwire
Reflector
Risk InstanceYLogon credential check failed
PARSE_ERRORwire
Reflector
FIX Message ParserYMessage syntax error
EXPIREDmetronomeSessionStoreYSession heartbeat expired
SEND_FAIL_LIMITwireSessionStoreNsend() failed too many times 
TRADER_IP_REMOVEDweb serverSessionStoreYAssociated trader IP removed
VENUE_IP_REMOVEDweb serverSessionStoreYAssociated venue IP removed
CREDENTIAL_DISABLEDweb server
Reflector
Risk InstanceYAssociated credential disabled
GROUP_DISABLEDweb server
Reflector
Risk InstanceYAssociated risk pool disabled
DEAD_MAN_SWITCHmetronome
Reflector
Risk InstanceYRisk pool DMS heartbeat expired
SHUTDOWNweb server
Reflector
Risk InstanceYShutdown command received


Broken Session

If Reflector receives a TCP packet that fits the following requirements, it swallows the packet and generates a TCP RST packet in the reverse direction

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