Cryptographic. A cryptographic solution to achieve confidentiality is using encryption. An encryption function maps a plain text into a chipper text (meaningless data) for given key. An encryption scheme is said to be symmetric-key if encrypting key is equal to decrypting key, it is computationally easy. Thus two parties wishing to communicate securely need to share the key over some secure channel before they can use the encryption scheme to communicate over an insecure channel. In contrast, in asymmetric-key systems it is infeasible to determine decrypting key from given encrypting key. Thus every user in such a system has a key pair both encrypting and decrypting key which is unique to them. This scheme does away with the need for a secure channel at any time. While symmetric-key techniques are much faster than asymmetric ones, they require the parties to have a pre-shared secret. Thus a common solution is to exchange a symmetric key using asymmetric technique. This holds particularly true for mobile ad hoc networks as the use of asymmetric-key cryptography for securing all communication is practically impossible.
Cryptographic. Information is information (including crypto-material) significantly descriptive of cryptographic techniques and processes or of cryptosystems and equipments or their functions and capabilities, the disclosure of which would assist the crypto-analytic solution of an encrypted test or a cryptosystem. Cryptographic information is always classified. Defence Innovation Hub – Innovation Contract – SCCG (V1.0) [Defence to insert security classification] Annexure F – TD Schedule [TD Schedule developed by the Participant at the RFP stage to be included. At the Effective Date, this Annexure is likely to include only TD comprising Background IP. This Annexure must be updated by the Participant as the work under the contract is undertaken and new TD is produced.] The Defence Representative and the Participant Representative may agree in writing to update the TD Schedule without entering into a deed in accordance with clause 38.1. Technical Data Description Form of Technical Data
Cryptographic primitives We limit ourselves to cryptographic primitives that must be supported for the mandatory TLS support in OCPP and OCPI. This means we will use: • AES-128-GCM for AE, and • ECDHE on NIST-P-256 curve for key encapsulation. • SHA256 and HMAC-SHA256 for (keyed) hashing. • ECDSA on NIST-P-256 curve for digital signatures. The encryption in step 4 is performed according to JWE [8]. We use Elliptic Curve Xxxxxx-Xxxxxxx Ephemeral Static for key agreement (ECDH-ES) (see [8, app. C] for an example), so that requirement 5 (offline operation) is met. For the keyedhash functions used in step 6, we sug- gest using HMAC. The values in the document should be BASE64URL-encoded 256-bit output. For the hashing in step 8, we suggest a normal hash on the BASE64URL represen- tation of the JSON document, similar to how signatures are computed in JWS. The signature in step 10 is performed according to JWS [7]. We suggest using ECDSA on curve P-256 with SHA256 (see [7, app. A.3] for an example). To add ciphertexts and signatures to documents and mes- sages, we suggest using the compact serializations defined by JWE and JWS. Regardless of serialization used, both the signature and ciphertext will contain a XXXX header. If default algorithms are used, then one could consider removing their corresponding fields from the header transmitted to the recipient. Having the recipient reinstate these fields themselves before decryption and signature verification would save a few bytes in overhead.
