[dtn-security] Issue implementing security source/destination with ESB blocks

[[e-mail]]

We've run into a problem while implementing the security source and
destination in the ESB blocks.  When ESB encapsulates a block, the BSP RFC
states that the eid ref list of the encapsulated block should be used as
the eid ref list of the encapsulating block, as in PCB.  However, the eid
ref list of the encapsulating block also needs to store the security
source and destination. We aren't sure if the eid ref list of the
encapsulated block should be appended to the eid ref list of the
encapsulating block.  The RFC states that an Abstract Security Block
should have at most 2 eid references, and this would contradict that
statement.

We get around this problem with PCB because the first PCB block's eid ref
list stores the security source and destination, and an extra PCB block is
added for any encapsulated blocks (and this extra PCB block contains the
eid ref list of the encapsulated block).  With ESB, there is a one-to-one
correspondence between the 'replacing' ESB block and the block to be
encapsulated, so we do not have an extra block as in PCB.



thanks,
Angela


Angela Hennessy
Laboratory for Telecommunication Sciences (LTS)