Transport Layer Decodes

Class TCP

Provides access to fields in a TCP header.

Instance Variables
src_port tcp.src_port -> anInteger
Source Port (16-bit)
sourcetcp.source -> anInteger
Synonym for src_port (deprecated)
dst_port tcp.dst_port -> anInteger
Destination Port (16-bit)
desttcp.dest -> anInteger
Synonym for dst_port (deprecated)
seq_nbr tcp.seq_nbr -> anInteger
Sequence Number (32-bit)
ack_nbr tcp.ack_nbr -> anInteger
Acknowledgement Number (32-bit)
doff tcp.doff -> anInteger
Data Offset (4-byte units); header is doff*4 bytes long
urg? tcp.urg? -> true or false
True if 'Urgent' flag is 1
ack? tcp.ack? -> true or false
True if 'Acknowledge' flag is 1
psh? tcp.psh? -> true or false
True if 'Push' flag is 1
rst? tcp.rst? -> true or false
True if 'Reset'' flag is 1
syn? tcp.syn? -> true or false
True if 'Synchronise' flag is 1
fin? tcp.fin? -> true or false
True if 'Finish' flag is 1
window tcp.window-> anInteger
Receive Window size
checksum tcp.checksum -> anInteger
TCP Checksum
urg_ptr tcp.urgent -> anInteger
TCP Urgent Pointer 

Nevil Brownlee
Tue, 23 Dec 08 (NZDT)