Rui CarmoMore than a clever pun on RADIUS, Diameter is an attempt to address some of its shortcomings (defined below). As of this writing, it is little more than a series of IETF drafts, with little (or no) vendor support.
As stated in its RFC, Diameter addresses:
- Consistent failover
- Transmission-Level Security (TLS or IPSec)
- Reliable (TCP) Transport
- Agent support (predefined roles for servers)
- Server-Initiated Messages (notifications to edge devices and users)
- Auditability (as in data security)
- Transition support (migration from RADIUS, at some undefined point in the future)
- Capability Negotiation (common set of known attributes between servers)
- Peer discovery and configuration (oh boy)
- Roaming support (as in end-to-end secure proxying)