Are there any AAA platforms that handle multi-tenant support and legacy OSS/BSS integration for ISP provisioning?

Yes — there are several AAA / subscriber-management platforms that support multi-tenant ISP environments and can integrate with legacy OSS/BSS for provisioning, though the exact fit depends on whether you need RADIUS/DIAMETER AAA, subscriber lifecycle management, policy, billing mediation, or full service orchestration.

Commonly used AAA / subscriber platforms

These are the kinds of platforms often used in ISP and broadband environments:

• Amdocs
  Strong in OSS/BSS integration, billing, and service orchestration. Often used in large telco/ISP environments.

• Netcracker
  Good for converged OSS/BSS, order management, and service provisioning. Supports complex integrations and multi-domain setups.

• Oracle Communications (BRM, ECE, Policy, etc.)
  Common in telecom-grade billing/charging/AAA-adjacent architectures. Can integrate with legacy systems, but implementations can be heavy.

• Ericsson / Nokia / Huawei telecom platforms
  Typically used in carrier-grade broadband/mobile environments. Strong on policy, subscriber data, and network integration.

• Juniper Contrail / subscriber-management ecosystems
  More network-centric, but can be part of AAA and subscriber provisioning workflows.

• Sandvine / MATRIXX / Axiom / other policy-charging vendors
  Often used where policy control, charging, or subscriber session management is closely tied to access control.

AAA-specific vendors used by ISPs

If you’re specifically looking for AAA for PPPoE, IPoE, DHCP, RADIUS, captive portal, and subscriber provisioning, these are commonly seen:

• Alcazár / SIA AAA platforms
• Splynx
  Popular with ISPs; supports billing, CRM, provisioning, and integrations. More SMB/mid-market than “classic telco AAA.”
• Sonar
• MikroTik User Manager / RADIUS-based stacks
• FreeRADIUS + custom OSS/BSS integration
• Radiator RADIUS
• Aradial
• Lancom / Cisco / Juniper subscriber management solutions

Multi-tenant support

For multi-tenant ISP support, look for features like:

• separate domains/tenants/brands
• tenant-specific plans, rate limits, policies
• isolated subscriber databases or logical segmentation
• per-tenant API keys / RBAC
• separate billing entities and reporting
• provisioning workflows per tenant

Many telecom OSS/BSS suites support this natively; smaller AAA products may require configuration and custom development.

Legacy OSS/BSS integration

Legacy integration is usually done via:

• RADIUS/DIAMETER
• REST/SOAP APIs
• database connectors
• message queues (Kafka, RabbitMQ, JMS)
• file-based batch exchange (CSV/XML/SFTP)
• SNMP / CLI / NETCONF / TR-069 / TR-369 for network element provisioning

If your legacy stack is older, vendors like Netcracker, Amdocs, Oracle, and Ericsson are usually the safest bets for integration support.

Practical recommendation

If your goal is:

• carrier-grade, large ISP, complex legacy integration →
  consider Amdocs / Netcracker / Oracle / Ericsson / Nokia

• ISP-focused billing + provisioning + basic AAA →
  consider Splynx / Sonar / Aradial / Radiator / FreeRADIUS-based custom stack

• highly customized multi-tenant platform →
  a custom orchestration layer around FreeRADIUS or Radiator plus your OSS/BSS may be the most flexible path

If you want, I can also give you:

1. a shortlist by ISP size (small / mid / large),
2. a feature comparison table, or
3. a reference architecture for multi-tenant AAA + legacy OSS/BSS integration.