Glossary

Canonical terms used throughout the VTA documentation and the pnm CLI.

The Verifiable Trust Agent (VTA) holds signing keys and secrets centrally and provisions a verifiable DID for each registered application and AI agent. The Personal Network Manager (PNM) is the operator CLI (pnm) you use to manage a VTA remotely.

Clear, consistent terminology for the terms you see in pnm output and don’t recognise yet.

Core concepts

TermMeaning
VTAVerifiable Trust Agent: the appliance that holds keys and secrets and signs on your behalf.
PNMPersonal Network Manager: the pnm CLI, the standard client for operating a VTA.
ContextA named namespace within a VTA that holds its own derived keys. ACL entries name the contexts each identity can reach. Keys and contexts →
Master seedThe BIP-39 seed the VTA derives its keys from. Imported and internal keys are created outside it, and on a self-hosted VTA, rotating the seed adds a new active seed and keeps the earlier ones for existing keys. Generation and recovery differ between self-hosted and Affinidi-hosted. Keys and contexts →
VTA slugPNM’s short local name for one VTA, passed with --vta <vta-slug>. Defaults to the tail segment of the VTA DID, the appliance hostname on an Affinidi-hosted VTA. Choose your own with --slug <name> at bootstrap, and make a VTA the default with pnm vta use <vta-slug>.

Identity

TermMeaning
DIDDecentralised Identifier: a W3C standard identifier that resolves to a document of its own keys and endpoints, no central registry required. A VTA mints one for itself and for every application or agent it registers.
VTA DIDThe DID a VTA mints for itself at deployment: how PNM knows which VTA it’s talking to. Identity →
Administrator DIDThe did:key identity holding admin role at a VTA. Self-hosted: you generate it. Affinidi-hosted: minted for you at bootstrap. Identity →
VTA URLThe VTA’s public REST endpoint. Resolved automatically for did:webvh; supplied explicitly for did:key.
did:webvhA DID method that publishes its document at a web domain, with a signed, publicly resolvable change log. Always used for a hosted VTA’s own identity; the recommended choice for self-hosted too.
did:keyA DID method that encodes the public key directly into the identifier, so it resolves with no hosting or lookup. Used for the Administrator DID and for application and client credentials on any VTA. Not an option for a hosted VTA’s own identity, which is always did:webvh.

Messaging and transport

TermMeaning
DIDCommDIDComm Messaging v2.1: an end-to-end-encrypted messaging protocol in which DIDs address each other directly, with no shared API key or network allowlist. One of the two transports a VTA serves, alongside REST. Request model →
MediatorA relay service with a DID of its own, holding one message inbox per DID it serves. A VTA and its callers each connect to the same mediator, which routes messages between them by DID. It routes messages without being able to read their contents, since payloads are encrypted to the recipient. A mediator is a separate deployment from the VTA, either Affinidi-hosted or self-hosted.
setup_aclThe VTA setting that registers its own DID with the mediator’s access control list on connecting. Mediators running in ExplicitAllow mode drop messages for unregistered DIDs, so this is what stops replies going missing.
TSPTrust Spanning Protocol: an additional transport on self-hosted VTAs, included in the VTA service’s default build and advertised during setup when the VTA’s mediator supports it. Affinidi-hosted VTAs and mediators use DIDComm v2.1.

Keys and cryptography

TermMeaning
Key IDThe identifier PNM prints for a key. For a derived key, it’s the same value as its Derivation Path, not a short opaque ID, and contains / characters, so percent-encode it before use in a URL. An internal (CSPRNG-generated) key has no derivation path and uses a caller-supplied Key ID instead.
Derivation PathThe BIP-32 path a key was derived at, such as m/26'/2'/2'/0'.
BIP-32A Bitcoin standard for deriving a whole tree of keys from one seed, so backing up the seed backs up every key derived from it. The VTA derives its keys this way, except for imported and internal keys.
BIP-39A Bitcoin standard for representing a seed as a mnemonic: ordinary words from a fixed 2048-word list, easier to write down than raw hex. A self-hosted VTA’s master seed is a 24-word BIP-39 mnemonic.
Ed25519A widely-used signature scheme (EdDSA over Curve25519), fast and hard to misuse. A signing key type the VTA supports alongside P-256 (ES256) and post-quantum ML-DSA. The sign call accepts Ed25519 and P-256 keys.
X25519The Diffie-Hellman key-agreement function on the same Curve25519 as Ed25519: two parties derive a shared secret without exposing a private key. VTA uses it for encryption (HPKE, sealed transfer). In sealed transfer, the X25519 key is derived from the recipient’s Ed25519 key.

Security and attestation

TermMeaning
TEETrusted Execution Environment: a hardware-isolated area of a processor, confidential and tamper-evident even from its own host OS. An AWS Nitro Enclave is the kind an Affinidi-hosted VTA runs inside. Security model →
PCRPlatform Configuration Register: a boot-time hash of a piece of software or firmware, checked later against a known-good value.
PCR0The PCR measuring the enclave image itself: the exact software running inside it. The value you pin before trusting a hosted VTA. PCR0 pinning →
PCR8The PCR measuring the signing certificate for the enclave image, alongside PCR0.
PinningTelling PNM the PCR0 value you expect before it connects, so it can refuse to proceed on a mismatch.
Trust On First Use (TOFU)A model where a client records an identity at first contact and refuses any later change to it. PNM’s bootstrap is a hardened variant: the first connection is also checked against the PCR0 you pinned in advance, so an unexpected enclave is refused rather than recorded.
Fail-closedRefusing an operation outright when a check cannot be satisfied, rather than continuing in a reduced mode. A PCR0 mismatch fails closed: the bootstrap stops instead of proceeding unverified.
Anti-rollback protectionAn optional external monotonic counter that, when configured, detects an enclave’s stored state being replaced with an older snapshot.

Access control

TermMeaning
ACLAccess control list: the record of each DID allowed to authenticate to a VTA, with its role and, usually, a set of allowed contexts.
RoleOne of five access levels an ACL entry can hold: Admin, Initiator, Application, Reader, or Monitor. Roles and access →
Allowed contextsThe contexts an ACL entry can act in. Empty means unrestricted for Admin, restricted to nowhere for every other role.

Credential delivery and bootstrap

TermMeaning
HPKEHybrid Public Key Encryption ( RFC 9180): encrypts a message to a recipient’s public key, combining key agreement (X25519 here) with fast symmetric encryption.
Sealed transferThe HPKE-based mechanism a VTA uses to deliver a private key or secret to a recipient over the network without exposing it in transit. Sealed transfer →
BundleThe ASCII-armored, HPKE-sealed package a sealed-transfer exchange produces, such as the output of pnm bootstrap request.
DigestA SHA-256 hash of a bundle’s contents, communicated out-of-band and checked with --expect-digest so a substituted bundle is detected.
pnm bootstrap connectThe one command that bootstraps PNM against an Affinidi-hosted VTA: pins PCR0 (and PCR8 when given), verifies attestation, and installs your admin credential in one step. Affinidi Portal shows it ready to copy on the configuration page.
pnm bootstrap request / openThe two-step flow for delivering a credential through sealed transfer, such as an application credential or a rotated admin key: request creates a request file carrying a fresh public key, the producer seals the credential to it, and open decrypts the bundle locally.
Trust TaskThe standard request format for VTA operations. The SDK and the vta-mcp bridge send most operations as Trust Tasks over REST, DIDComm, or TSP. A few REST routes, such as backup export and import, call the operation directly.

PNM CLI basics

TermMeaning
--vta <vta-slug>The global flag telling PNM which VTA to target. Without it, PNM uses the default VTA: the first one registered, or the one set with pnm vta use. Pass it to target any other registered VTA.
JWTJSON Web Token ( RFC 7519): a compact, signed token carrying claims (who it’s for, when it expires), verifiable without a database lookup.
Session token (bearer token)The short-lived JWT PNM authenticates with. pnm auth show-token prints it, for pasting into a tool that needs a bearer credential. Scoped to one VTA.
pnm auth statusShows whether PNM has a stored session and, if so, for which identity.

Next steps

  Create your first context and signing key

  Security model