Section 3 — Surface · Talaia V2XIS service manual

3.1Resources

Resource map

ETSI GS MEC 030 [1] defines the V2X Information Service as eight resources under /vis/v2/. Talaia maps them one-to-one.

Method	Path	Resource
GET	/vis/v2/queries/uu_unicast_provisioning_info	Uu unicast provisioning · LTE/NR cells
GET	/vis/v2/queries/uu_mbms_provisioning_info	Uu MBMS provisioning
GET	/vis/v2/queries/pc5_provisioning_info	PC5 sidelink provisioning
GET	/vis/v2/subscriptions	Subscription registry
POST	/vis/v2/subscriptions	Create subscription
POST	/vis/v2/provide_predicted_qos	Predicted QoS along a route
POST	/vis/v2/provide_v2x_msg_distribution_server_info	Broker discovery · MQTT v5
POST	/vis/v2/publish_v2x_message	Publish a V2X message

3.2Provisioning

Radio access provisioning

The provisioning queries inform a MEC application of the radio layer reachable from the local edge. Talaia serves real Uu unicast data from the SkyV2X testbed cell. MBMS and PC5 are declared mocks until the real sources land in a later phase.

Listing 3.2-1 — Uu unicast provisioning

curl -sS https://mec.skyv2x.com/vis/v2/queries/uu_unicast_provisioning_info

Listing 3.2-2 — Uu MBMS and PC5 (declared mocks)

curl -sS https://mec.skyv2x.com/vis/v2/queries/uu_mbms_provisioning_info
curl -sS https://mec.skyv2x.com/vis/v2/queries/pc5_provisioning_info

3.3Subscriptions

Subscriptions and broker fan-out

A subscription scopes which V2X messages an integrator wants to receive. The platform matches by message type, geographic area and station type, then fans out via MQTT v5. The response carries the subscription body and the topic to consume.

Listing 3.3-1 — List active subscriptions

curl -sS https://mec.skyv2x.com/vis/v2/subscriptions

Listing 3.3-2 — Create a V2X message subscription

curl -sS -X POST https://mec.skyv2x.com/vis/v2/subscriptions \
  -H 'Content-Type: application/json' \
  -d '{
    "subscriptionType": "V2xMsgSubscription",
    "callbackReference": "mqtt://your-client/talaia/cpm",
    "filterCriteria": { "msgType": ["denm", "cpm"] }
  }'

3.4Errors

Error surface · RFC 7807

Per ETSI GS MEC 009 [2], every error response carries an RFC 7807 ProblemDetails body with media type application/problem+json. No HTML error pages, no plain text — the same shape applies on every 4xx and 5xx.

Listing 3.4-1 — Sample 400 response

HTTP/1.1 400 Bad Request
Content-Type: application/problem+json

{
  "type": "about:blank",
  "title": "Bad Request",
  "status": 400,
  "detail": "filterCriteria.msgType: must contain at least one value",
  "instance": "https://mec.skyv2x.com/vis/v2/subscriptions"
}

3.5Discovery

Discovery surface

Three machine-readable summaries make integration without documentation viable.

GET /vis/v2/capabilities declares what Talaia claims to implement, version-pinned. GET /vis/v2/status.json exposes the live operational state, counters and broker connection. GET /vis/v2/conformance returns the conformance audit verdict.

3.6Caveat

Testbed caveat

Talaia is open for integrators and researchers. The provisioning data describes the SkyV2X internal cell — adequate for spec-strict integration testing, not for production radio attachment. The testbed runs without authentication; any deployment that handles real traffic sits behind a token-validating gateway and signs outbound V2X via Castell.