1. A method comprising: generating, at a computer, a landlord key pair and a tenant key pair, each key pair including a private key and a public key, the landlord key pair being used to establish secure communication between the computer and a landlord device, and the tenant key pair being used to establish secure communication between the computer and a tenant device; keeping the landlord private key and the tenant private key secure at the computer without disclosing the keys to any other device; forwarding the landlord public key and the tenant public key to the landlord device; and forwarding the tenant public key to the tenant device: