The value of tmnxBsxAarpInstPeerEPSapEncap along with
tmnxBsxAarpInstPeerEPSapPortId and tmnxBsxAarpInstPeerEPSapEncType
specifies the Service Access Point (SAP) end point for the dual
homed peer.
The specification of a tmnxBsxAarpInstPeerEPSapEncap is mutually
exclusive with the specification of tmnxBsxAarpInstPeerEPSdpBindId.