High-level Entity Management Protocol (HEMP) (RFC1022)
Original Publication Date: 1987-Oct-01
Included in the Prior Art Database: 2000-Sep-12
Internet Society Requests For Comment (RFCs)
C. Partridge: AUTHOR [+2]
STATUS OF THIS MEMO
Network Working Group C. Partridge
Request For Comment: 1022 BBN/NNSC
THE HIGH-LEVEL ENTITY MANAGEMENT PROTOCOL (HEMP)
STATUS OF THIS MEMO
An application protocol for managing network entities such as hosts,
gateways and front-end machines, is presented. This protocol is a
component of the High-Level Entity Management System (HEMS) described
in RFC-1021. Readers may want to consult RFC-1021 when reading this
memo. This memo also assumes a knowledge of the ISO data encoding
standard, ASN.1. Distribution of this memo is unlimited.
The High-Level Entity Management Protocol (HEMP) provides an
encapsulation system and set of services for communications between
applications and managed entities. HEMP is an application protocol
which relies on existing transport protocols to deliver HEMP messages
to their destination(s).
The protocol is targeted for management interactions between
applications and entities. The protocol is believed to be suitable
for both monitoring and control interactions.
HEMP provides what the authors believe are the three essential
features of a management protocol: (1) a standard encapsulation
scheme for all interactions, (2) an authentication facility which can
be used both to verify messages and limit access to managed systems,
and (3) the ability to encrypt messages to protect sensitive
information. These features are discussed in detail in the following
HEMP is designed to support messages; where a message is an
arbitrarily long sequence of octets.
Five types of messages are currently defined: request, event, reply,
and protocol error, and application error messages. Reply, protocol
error and application error messages are only sent in reaction to a
request message, and are referred to collectively as responses.
Two types of interaction are envisioned: a message exchange between
an application and an entity managed by the application, and
unsolicited messages from an entity to the management centers
responsible for managing it.
When an application wants to retrieve information from an entity or
gives instructions to an entity, it sends a request message to the
entity. The entity replies with a response, either a reply message
if the request was valid, or an error message if the request was
invalid (e.g., failed authentication). It is expected that there
will only be one response to a request message, although the protocol
does not preclude multiple responses to a single request.
Protocol error messages are generated if errors are found when
processing the HEMP encapsulation of the message. The possible