We describe the use of property-based peer trust to provide security in Sleeper, a new energy-efficient service discovery protocol which uses proxied advertisement and discovery to dynamically offload service discovery workload from power-limited devices. Property-based digital certificates have previously been used in trust-negotiation methods. In earlier work we developed a new method for secure and private peer-to-peer trust negotiation using property-based digital certificates and a secure trust negotiation agent. Here we describe how propertybased peer trust can be used to secure the Sleeper service discovery protocol.