Line Profiles

A line profile is a reusable service class: every setting that describes what kind of line this is rather than whose line it is. Hundreds of lines typically share a handful of profiles — standard, executive, lobby, fax — and upgrading a subscriber is a one-field change on the line.

line-profiles:
  standard:
    inbound-translation-context: from-lines
    screening-context: no-premium
    calling-features: [voicemail, dnd, cfa, cfb, cfna]
    feature-code-map: standard
    codecs: [g722, ulaw, alaw]

Field reference

Field	Required	Meaning
inbound-translation-context	yes	The translation context walked for every number lines with this profile dial — including forward targets and voicemail callback.
screening-context	no	Destination screening applied after translation, before dialing. Empty = unrestricted.
special-number-profile	no	Which special-number profile intercepts emergency numbers for these lines. Empty = the default profile.
calling-features	no	The feature entitlements granted to these lines (below).
max-ring-time	no	Seconds a call rings these lines’ devices before no-answer handling (voicemail / CFNA) takes over. Default 25. A subscriber’s own call-forward-no-answer timeout, when set, overrides it for that line.
feature-code-map	no	Which feature-code map these lines can dial. Empty = no star codes.
allow-unrestricted-caller-id	no	Let devices assert their own external caller ID (below). Default off.
codecs	no	Ordered codec policy for these lines (below). Empty = no restriction.
max-concurrent	no	Template concurrent-call cap applied to each line individually. A line’s own max-concurrent overrides it. Zero/absent = unlimited.

Calling features — entitlement, not state

calling-features lists what lines with this profile are allowed to use. The subscriber-facing state itself (DND on/off, forward targets, speed dials) is managed per line through the API or portal:

Flag	Grants
voicemail	Unanswered/busy/DND calls fall to the line’s mailbox; without it, a configured mailbox is ignored
dnd	Do-not-disturb
cfa	Call-forward always
cfb	Call-forward on busy
cfna	Call-forward on no-answer (with configurable timeout)
spam	Accepted for a future inbound spam-screening capability; no effect in this release

Entitlement is enforced on both sides:

• The management API refuses to set feature state a line’s profile doesn’t grant.
• At call time, existing state for a non-granted feature is ignored — so downgrading a profile immediately disables the features it revoked, without touching stored subscriber state. Re-granting the feature brings the old state back.

Two flags decide whether voicemail answers

Calls reach a mailbox only when the line has a voicemail box and the profile grants the voicemail feature. A profile without the feature turns every would-be voicemail drop into the failure treatment — usually the symptom behind “callers hear fast-busy instead of voicemail” after a profile change.

Caller-ID enforcement

By default the switch enforces line caller ID: whatever a device puts in its From header is discarded and the line’s configured caller-id / internal-caller-id are presented. Subscribers cannot spoof.

allow-unrestricted-caller-id: true relaxes this for the profile: a presented caller ID passes through (falling back to the configured one when the device sends nothing). Reserve it for trusted use cases — a PBX behind registered devices asserting its own DID block, a call-center presenting campaign numbers — and remember that as the operator you remain responsible for the identities your lines originate with.

This choice also sets the STIR/SHAKEN stakes: when your namespace signs outbound calls, line-originated calls are signed at attestation A (the switch enforced the caller ID) — but lines on an unrestricted profile are signed at B, since the asserted number wasn’t verified.

Codec policy

codecs is an ordered list of permitted codecs (Asterisk names — ulaw, alaw, g722, g729, opus, gsm, ilbc, and the other names in the codec appendix):

• Inbound offers from these lines’ devices are stripped to this set at the edge; an offer with no permitted codec is refused with SIP 488 before anything rings.
• Outbound dials to these lines offer this set, in listed order of preference.
• Empty means no policy — whatever the endpoints negotiate passes through.

Keep the list short and put your preferred codec first: [g722, ulaw] gives HD audio between capable endpoints with a universal fallback.

Worked profiles

line-profiles:
  # Full-featured knowledge-worker line.
  executive:
    inbound-translation-context: from-lines
    calling-features: [voicemail, dnd, cfa, cfb, cfna]
    feature-code-map: standard
    codecs: [g722, ulaw]

  # Courtesy phone: internal-only, no features, no star codes.
  lobby:
    inbound-translation-context: from-lines
    screening-context: internal-only
    max-concurrent: 1

  # Fax / analog adapter: G.711 only, nothing clever.
  fax:
    inbound-translation-context: from-lines
    codecs: [ulaw]

  # Call-center line asserting campaign caller IDs.
  dialer:
    inbound-translation-context: from-dialer
    allow-unrestricted-caller-id: true
    screening-context: domestic-only
    codecs: [ulaw]

All four share translation contexts and screening contexts defined once — profiles are where the reusable pieces are bundled into a sellable class of service.