11110001 00110101 - Confidential 01111000 10011010 - EFTO 10111100 01001101 - MMMM 01011110 00100110 - PROG 10101111 00010011 - Restricted 11010111 10001000 - Secret 01101011 11000101 - Top Secret 00110101 11100010 - (Reserved for future use) 10011010 11110001 - (Reserved for future use) 01001101 01111000 - (Reserved for future use) 00100100 10111101 - (Reserved for future use) 00010011 01011110 - (Reserved for future use) 10001001 10101111 - (Reserved for future use) 11000100 11010110 - (Reserved for future use) 11100010 01101011 - (Reserved for future use)
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September 1981 Internet Protocol Specification
Compartments (C field): 16 bits
An all zero value is used when the information transmitted is not compartmented. Other values for the compartments field may be oBTained from the Defense Intelligence Agency.
Handling Restrictions (H field): 16 bits
The values for the control and release markings are alphanumeric digraphs and are defined in the Defense Intelligence Agency Manual DIAM 65-19, "Standard Security Markings".
Transmission Control Code (TCC field): 24 bits
Provides a means to segregate traffic and define controlled communities of interest among subscribers. The TCC values are trigraphs, and are available from HQ DCA Code 530.
Must be copied on fragmentation. This option appears at most once in a datagram.
Loose Source and Record Route
+--------+--------+--------+---------//--------+ 10000011 length pointer route data +--------+--------+--------+---------//--------+ Type=131
The loose source and record route (LSRR) option provides a means for the source of an internet datagram to supply routing information to be used by the gateways in forwarding the datagram to the destination, and to record the route information.
The option begins with the option type code. The second octet is the option length which includes the option type code and the length octet, the pointer octet, and length-3 octets of route data. The third octet is the pointer into the route data indicating the octet which begins the next source address to be processed. The pointer is relative to this option, and the smallest legal value for the pointer is 4.
A route data is composed of a series of internet addresses. Each internet address is 32 bits or 4 octets. If the pointer is greater than the length, the source route is empty (and the recorded route full) and the routing is to be based on the destination address field.
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September 1981 Internet Protocol Specification
If the address in destination address field has been reached and the pointer is not greater than the length, the next address in the source route replaces the address in the destination address
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