Hewlett"Packard reserves certain SAPs for operation of HP software. They are:
F0 (hex): | (reserved) |
F4 (hex): | HP Link Level LAN Diagnostic Software DSAP |
F8 (hex): | HP Network and Node Manager Software DSAP |
| (also may be used for remote VCP and FCL) |
FC (hex): | HP Network Services DSAP for PROBE protocol |
Source Service Access Point (SSAP) Address
The Logical Link Control SSAP field contains a single address that identifies a service access point (SAP) from which the information field is sent. (Note that Group SSAPs are not defined.) The format of the SSAP address field is as follows:
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| S |
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S | indicates SSAP address bits |
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Sx | 0 indicates the SSAP is locally administered (user"defined) | |||||||||||||
| 1 indicates it is administered by the IEEE (see below) | |||||||||||||
C/R | is a Command/Response bit indicating whether the packet data from this | |||||||||||||
| SSAP is an initial outgoing command, or a response resulting from some | |||||||||||||
| previous incoming command, as follows: | |||||||||||||
C/R = 0 Packet data is a command from this SSAP
C/R = 1 Packet data is a response from this SSAP
A legal (user"defined) SSAP address takes the following form (note the •0" in the second bit):
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Last Bit |
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| Legal SSAP Address |
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2%10 General Information