A key management technique establishes a secure channel through an
indeterminate number of nodes in a network. The technique comprises
enrolling a smart card with a unique key per smart card. The unique key
is derived from a private key that is assigned and distinctive to systems
and a card base of a card issuer. An enrolled smart card contains a
stored public entity-identifier and the secret unique key. The technique
further comprises transacting at a point of entry to the network. The
transaction creates a PIN encryption key derived from the smart card
unique key and a transaction identifier that uniquely identifies the
point of entry and transaction sequence number. The technique also
comprises communicating the PIN encryption key point-to-point in
encrypted form through a plurality of nodes in the network, and
recovering the PIN at a card issuer server from the PIN encryption key
using the card issuer private key.