Here is the beginning of a proposed Internet standard submitted by Microsoft
and HP for a simple service discovery protocol. I've abstracted up to
section 1 of it. The rest can be found in the Internet-Drafts directory. I
suspect that this is a competitor for
SLP, correct? How do the two compare?
Internet Engineering Task Force Ting Cai
INTERNET DRAFT Paul Leach
Yaron Y. Goland
April 8, 1999
Expires September 1999
Simple Service Discovery Protocol/1.0
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
This document is an Internet-Draft. Internet-Drafts are working
documents of the Internet Engineering Task Force (IETF), its areas,
and its working groups. Note that other groups may also distribute
working documents as Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six
months and may be updated, replaced, or obsoleted by other documents
at any time. It is inappropriate to use Internet- Drafts as
reference material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at
The list of Internet-Draft Shadow Directories can be accessed at
The Simple Service Discovery Protocol (SSDP) provides a mechanism
where by network clients, with little or no static configuration,
can discover desired network services. SSDP uses HTTP over multicast
and unicast UDP to provide two functions: OPTIONS and ANNOUNCE.
OPTIONS is used to determine if a desired network service exists on
the network. ANNOUNCE is used by network services to announce their
With the growing number of small peer-to-peer TCP/IP networks, such
as home or small office networks, computer users need a way to
discover resources in a network easily, quickly, dynamically, and
without any a priori knowledge. This document proposes a discovery
protocol that meets this user requirement.
INTERNET-DRAFT SSDP/V1 April 8, 1999
The proposed protocol is called the Simple Service Discovery
Protocol (or SSDP). SSDP performs only discovery. It leaves any
additional service description and/or negotiation to a higher layer
Using SSDP, operating systems and applications can discover SSDP-
enabled services in a network dynamically by issuing service
queries. Services that match the queries respond with their network
locations and protocols to be used to communicate with them. In
addition, services can make their presence known through unsolicited