Overview
ISO/IEC 11518-3:1996 (HIPPI-LE) specifies how to encapsulate ISO/IEC 8802-2 (IEEE 802.2) Logical Link Control (LLC) Protocol Data Units (PDUs) for transport over the High-Performance Parallel Interface (HIPPI). The standard defines the HIPPI‑LE PDU format, the interface and service primitives between HIPPI‑LE and higher‑layer LLC, and the mechanisms needed to forward 48‑bit MAC-style addresses and resolve those addresses to HIPPI switch addresses.
Key Topics
- Encapsulation of IEEE 802.2 LLC PDUs: Defines how arbitrary ISO/IEC 8802-2 LLC PDUs are packaged into HIPPI‑LE PDUs (LE Header + D2 area) for transmission over HIPPI.
- PDU and data formats: HIPPI‑LE header and D2 data area formatting rules (see clause 6). The document notes mapping of 6‑byte ISO/IEC 8802‑2 MAC addresses into HIPPI words.
- Service primitives: Four primitive types-Request, Confirm, Indicate, Response-and specific HIPPI‑LE primitives (e.g., LE‑TRANSFER, LE‑ADDRESS‑RESOLUTION, LESM status/control) used to integrate LLC and station management with HIPPI services.
- Addressing and resolution: Support for ISO/IEC 8802‑2 48‑bit source/destination addresses and an address resolution mechanism to map higher‑level addresses to HIPPI switch addresses. HIPPI‑SC defines switch address formats (Logical Address - 12 bits; Source Route - 24 bits).
- Forwarding classes: Provision for eight forwarding classes to distinguish QoS or service types (e.g., bulk data vs. bandwidth‑sensitive streams).
- Interaction with HIPPI‑FP: HIPPI‑LE uses HIPPI Framing Protocol (HIPPI‑FP) services for lower‑level transfer; implementers must consider D2‑Offset effects on performance.
Applications and Users
This standard is relevant for:
- Network and systems engineers integrating HIPPI interconnects with IEEE 802.2 LLC‑based protocols.
- Hardware and firmware developers building HIPPI NICs, switches, or framing protocol (HIPPI‑FP) interfaces.
- HPC and storage system architects working with legacy or specialized high‑bandwidth interconnects that require robust encapsulation of LAN/MAC‑style traffic.
- Vendors implementing station management (SMT) and address resolution services on HIPPI fabrics.
Practical uses include transporting LAN/LLC PDUs across point‑to‑point or switched HIPPI links in environments requiring high throughput and deterministic forwarding behavior.
Related Standards
- ISO/IEC 11518-1 - HIPPI mechanical, electrical and signaling protocol (HIPPI‑PH)
- ISO/IEC 11518-2 - HIPPI Framing Protocol (HIPPI‑FP)
- ISO/IEC 11518-4/5/6 - other HIPPI mappings and services (HIPPI‑IPI, HIPPI‑MI, HIPPI‑SC)
- ISO/IEC 8802-2 - IEEE Std 802.2 Logical Link Control (LLC)
- HIPPI-SC - Physical Switch Control (for switch address formats)
Keywords: ISO/IEC 11518-3, HIPPI-LE, HIPPI, encapsulation, ISO/IEC 8802-2, IEEE 802.2, LLC PDU, 48-bit address, address resolution, HIPPI-FP.